[Group] SBF DUCATI Monster

[hnn]

Got a question for you monster experts. Something i've been wondering for quite a while now

 

Do any of you guys notice a power 'flat spot' at very low revs? It is most pronounced when moving off from a standstill. If you apply medium-to-low throttle input and try to move off at a relaxed pace the bike kind of chokes a bit and there is an obvious sluggishness for about a split second before the revs enter the lower midrange when the power comes in. I can't say at what particular rev this flat spot occurs as i don't have a tacho on the monsters that I have ridden, but the rpm is definitely low, probably below 3000rpm. But its a problem almost identical on both my older monster 400 and this 900 which leads me to think its not a problem unique to my bike, but to monsters in general

 

When doing a slightly more aggressive launch the flat spot is bypassed since the revs stay high from moving off and you're grinding the hell out of the clutch. But aggresive launching from traffic lights is not my riding style unless I'm intent on going nuts. Most of the time its just go slow and shift early. Attempting a smooth low rev launch is simply not possible without encountering that flat spot.

 

When i owned my old 400 and complained to Mike about the flat spot he told me a 400 is a slow bike and i couldn't expect much. Made sense at the time, but now that i'm getting a similar thing on the 900, i'm really starting to wonder.

 

I tried searching high and low on ducatimonster.org but the closest i could find to a cause was gearing. The discussions there seemed to imply this problem came about from the stock sprocket setup of 15/38 which apparently got solved from a 14/40 combo but both my old monster 400 and monster 900 are already on 14T fronts and 44T for the rear of the 400 and currently 41T on the 900. The problem is still there. I've noticed many people here experiencing this same problem, seen it mentioned a few times all over, including here, i was wondering if a solution exists. If not i may just go ahead with a 42-44T rear sprocket on the 900 and see if that works but somehow i don't think this is the solution

 

If anyone has any suggestions i'm all ears

 

P.S do any of you have suggestions on a good sprocket size combo for the m900 for mostly city riding with good acceleration from standstill? My fastest (and i rarely ever go this fast except for very short bursts) typical highway cruise speed is 140kmh. Typically i cruise at 100-120kmh depending on traffic conditions. As long as the sprocket combo allows my bike to cruise comfortably at 150-160kmh (in case i decide to go touring) without any risk of over-rev, i'm happy.

Try changing to a better oil filter ie K&N? Engine would breathe a bit better. Reckon youre still on stock pipes? Those play a part in low end torque also. Good luck.

[Duke_Monster]

blackreplica: i get this problem too. i kinda dismissed the problem because i assumed it was only 400cc.(on a bike weight tht is meant for a 620cc, i mean ducati designed e monster w a min. engine capacity of 620, its due to e japan market tht they downbored it to 400cc) but since u also experiencing the problem i guess it's just the inherit nature of monsters? character? haha.

 

as hann mentioned a better filter(k&n) and better breathing pipes would probably improve e situation? u can core yr 748 stock pipes at u know where for a few hundred bucks if u wish to keep yr current look intact..

[motocafe]

Try changing to a better oil filter ie K&N? Engine would breathe a bit better. Reckon youre still on stock pipes? Those play a part in low end torque also. Good luck.

 

blackreplica,

 

Your monster already has the K&N filter so that part is already done.

 

I changed the gearing (as you noticed - 41T rear) so it's actually better than what it used to be. In fact, I did try Dyno-jets, changing needle positions, etc but that only made things worse. So, the carb jettings are optimum as is. Personally, I think the standard Mikunis are the problem so I learned to live with it. Toyed with the idea of replacing them with Keihin FCRs but as usual never got around to doing it.

[antonioshabirto]

blackreplica: i get this problem too. i kinda dismissed the problem because i assumed it was only 400cc.(on a bike weight tht is meant for a 620cc, i mean ducati designed e monster w a min. engine capacity of 620, its due to e japan market tht they downbored it to 400cc) but since u also experiencing the problem i guess it's just the inherit nature of monsters? character? haha.

 

as hann mentioned a better filter(k&n) and better breathing pipes would probably improve e situation? u can core yr 748 stock pipes at u know where for a few hundred bucks if u wish to keep yr current look intact..

 

i have a spare core 748 exhaust. anyone keen can pm me. lots if other spare items too.

[Randy_koh]

i have a spare core 748 exhaust. anyone keen can pm me. lots if other spare items too.

 

I'm looking for front and back carbon mud guard... Pls call me @ 90710855 if u have.. thanks...

[technicolorhighway]

Got a question for you monster experts. Something i've been wondering for quite a while now

 

Do any of you guys notice a power 'flat spot' at very low revs? It is most pronounced when moving off from a standstill. If you apply medium-to-low throttle input and try to move off at a relaxed pace the bike kind of chokes a bit and there is an obvious sluggishness for about a split second before the revs enter the lower midrange when the power comes in. I can't say at what particular rev this flat spot occurs as i don't have a tacho on the monsters that I have ridden, but the rpm is definitely low, probably below 3000rpm. But its a problem almost identical on both my older monster 400 and this 900 which leads me to think its not a problem unique to my bike, but to monsters in general

 

When doing a slightly more aggressive launch the flat spot is bypassed since the revs stay high from moving off and you're grinding the hell out of the clutch. But aggresive launching from traffic lights is not my riding style unless I'm intent on going nuts. Most of the time its just go slow and shift early. Attempting a smooth low rev launch is simply not possible without encountering that flat spot.

 

When i owned my old 400 and complained to Mike about the flat spot he told me a 400 is a slow bike and i couldn't expect much. Made sense at the time, but now that i'm getting a similar thing on the 900, i'm really starting to wonder.

 

I tried searching high and low on ducatimonster.org but the closest i could find to a cause was gearing. The discussions there seemed to imply this problem came about from the stock sprocket setup of 15/38 which apparently got solved from a 14/40 combo but both my old monster 400 and monster 900 are already on 14T fronts and 44T for the rear of the 400 and currently 41T on the 900. The problem is still there. I've noticed many people here experiencing this same problem, seen it mentioned a few times all over, including here, i was wondering if a solution exists. If not i may just go ahead with a 42-44T rear sprocket on the 900 and see if that works but somehow i don't think this is the solution

 

If anyone has any suggestions i'm all ears

 

P.S do any of you have suggestions on a good sprocket size combo for the m900 for mostly city riding with good acceleration from standstill? My fastest (and i rarely ever go this fast except for very short bursts) typical highway cruise speed is 140kmh. Typically i cruise at 100-120kmh depending on traffic conditions. As long as the sprocket combo allows my bike to cruise comfortably at 150-160kmh (in case i decide to go touring) without any risk of over-rev, i'm happy.

 

Dude,

i too have the same resume as you do.m400-m900.

 

i have come to understand wat the problem was.

b4 the italian stallion jap bike didnt use to give problems like this cause,frankly they are boring piece of machinery(kind like jap *orn).

 

after a much tweaking and disscussion from tall gearing ,feul air mixtures and sprockets...changes to this and that.its all futile to actually pin-point the exact cause some can argue it is all of the above some will say none.

 

Dukes r special (like women) threat them the right way,you get the right response.buy them gifts maintain her beauty she'll sometimes treats you like a king or chew you up spits yur balls into the fire and accuse you of something else.lol (thats is wat the duke designer said that inspred them = women,study the bike and you'll see why esp. the 916..looks like a women.)

 

what i did was all that was mentioned.still no change.then i tried the woman analogy.presto! all is gone.

 

Jus give a good balance of trottle and enough clutch release...you will get a smooth and aggressive ride that will put make yur face looked like it was beaten by a silly stick.

 

so sir,treat yur itallian girl with enough love and freedom,she'll treat you like FABIO.

 

And finally i think yur bike comes with and adjustable clutch release setting...can relly remember.from 1-4 try each number see what works for you and soon you'll be rewarded.

 

i think it goes something like this ?

kiss french ride italian

[GuiNNeSS]

~~~~

 

If anyone has any suggestions i'm all ears

 

P.S do any of you have suggestions on a good sprocket size combo for the m900 for mostly city riding with good acceleration from standstill? My fastest (and i rarely ever go this fast except for very short bursts) typical highway cruise speed is 140kmh. Typically i cruise at 100-120kmh depending on traffic conditions. As long as the sprocket combo allows my bike to cruise comfortably at 150-160kmh (in case i decide to go touring) without any risk of over-rev, i'm happy.

 

Yo bro, its a Ducati thing. Even my old 999 stumbles alitle at very low rpms ie. Below 2500rpms. It might have something to do with the 90degree cylinder configuration, but certainly doesn't help city riding, especially with Ducati's habit of putting very tall 1st gears on their bikes. Just have to change your riding style to get around it.

 

As for your sprocket, its up to personal preferance, but I prefer to use my foot to drop a gear for better acceleration rather than to drop my gear ratios and sacrifice touring fuel economy.

[seraphx]

Dude,

i too have the same resume as you do.m400-m900.

 

i have come to understand wat the problem was.

b4 the italian stallion jap bike didnt use to give problems like this cause,frankly they are boring piece of machinery(kind like jap *orn).

 

after a much tweaking and disscussion from tall gearing ,feul air mixtures and sprockets...changes to this and that.its all futile to actually pin-point the exact cause some can argue it is all of the above some will say none.

 

Dukes r special (like women) threat them the right way,you get the right response.buy them gifts maintain her beauty she'll sometimes treats you like a king or chew you up spits yur balls into the fire and accuse you of something else.lol (thats is wat the duke designer said that inspred them = women,study the bike and you'll see why esp. the 916..looks like a women.)

 

what i did was all that was mentioned.still no change.then i tried the woman analogy.presto! all is gone.

 

Jus give a good balance of trottle and enough clutch release...you will get a smooth and aggressive ride that will put make yur face looked like it was beaten by a silly stick.

 

so sir,treat yur itallian girl with enough love and freedom,she'll treat you like FABIO.

 

And finally i think yur bike comes with and adjustable clutch release setting...can relly remember.from 1-4 try each number see what works for you and soon you'll be rewarded.

 

i think it goes something like this ?

kiss french ride italian

 

I'm really sorry to say this but I beg to differ...

 

No offense to anyone though.

 

The flat spot that you mention is actually caused by the tuning of your bike. Most of the M400s are carburator based. Hence, if you're running rich on either idle/pilot or needle jets, the overlap from the idle/pilot to the needle causes the flat spot, as the power is lost when the engine is unable to completely combust the mixture.

 

However, as soon as you pass the overlapping point, the needle jet is left in play and that is when a better mixture (slightly leaner as no overlapping of 2 jets) is obtained. You may also experience a flat spot on the higher revs when you gradually accelerate as there is also an overlapping point between your needle jet and your main jet.

 

Your mid-range or half-throttle is where the needle jet comes into play. When you are at WOT (Wide open throttle) or full throttle, that is when the needle jet is completely pulled out of your carb, with the slide, and the main jet is the one doing the whole job of controlling the air/fuel mixture.

 

Any carb based system will have this problem. As a matter of fact, you can ask any Aprilia RS125 rider if he experiences a flat spot at the 5k rpm mark and at the 8k rpm mark and I'd bet my entire paycheck, down to my last dollar, they would have it. I managed to actually tune it out of my bike just by dropping my jet sizes. It actually helped with my:

 

1) Fuel consumption. From 19km/l to 26km/l..

 

2) Power. Acceleration from standstill to top speed. From 21 seconds to 16 seconds. Top speed will have a slight variance. Mine actually increased by 6km/h.. from a 177km/h to 183km/h.

 

3) Response. You'll get much better response compared to running rich. Ask Randy, he has experienced the response of my bike first-hand. This does not mean you run lean. It just means that you're closer to the optimum efficiency setting for combustion.

 

4) Smoother power delivery. You'll get a smooth pickup at all rev ranges without the bogging at certain revs..

 

Hope this helps...

[blackreplica]

Guys, thank you all for the replies, its been very very helpful.

 

The issue is relatively minor i guess, but it irks me nonetheless.

 

When i'm in a hooligan kinda mood, the bike launches like a frakking legend and you couldnt wipe the smile off my face with a hammer and chisel. Its just when i want to relax and ride it nice and smooth and slow that the problem creeps up. which is a shame really because 90% of the time thats how i ride (at the end of the day, my own survival has to take priority LOL)

 

With my old M400, i went with a KNN filter and aftermarket GPR pipes but that was not the solution. I'm not sure if the exhaust system is the cause, but if it is, it will be solved soon. I already ordered the exhaust kit i linked to in my earlier post and its currently on the way here and will be installed very soon (standby for a review)

 

When i spoke to Mike about this problem the impression I got from his reply was that it was inherent in all monsters and required a different style of throttling from the way I am used to to launch the bike properly at low rates of acceleration. Incidentally I did a lot of riding today to try and develop a technique for a slow launch and am improving in getting it moving off smoothly even if doing it slowly. Requires more than average throttle input initially and then a gradual throttle reduction once the bike hits the midrange in first gear. Will get the hang of it eventually I think.

 

Seraphx> Your reply interests me. I usually hate to mess with carbs as they are so bloody temperamental and absolutely a ***** to deal with when things are done wrong but could you provide specifics on what jet sizes you were using? I take it you were riding an M900 as well?

 

Motocafe> Daniel I spoke to Mike earlier asking him if he remembered what the front sprocket size is on the monster. The first time i asked him a while back he confidently told me it was a 14T but asking him again he seemed hesistant and thinks now that maybe its a 15T. If in fact it was a 15 it would explain a lot based on the stuff i've been reading on DML. Did you fit a 14T to it or is it running on the stock 15T?

[blackreplica]

Toyed with the idea of replacing them with Keihin FCRs but as usual never got around to doing it.

 

heee that sounds like something I could do one day, which carbs did you have in mind? I believe there is a 39 and a 41 available from keihin (i might have got the numbers wrong tho). I'm thinking the smaller version so i don't mess up the low end. Those bloody keihins sure are expensive though. Time to add another mod to the wish list. Bloody ducatis...you just can't stop throwing money at them....its way too fun and addictive...good thing you did most of the hard work already haha

[seraphx]

Guys, thank you all for the replies, its been very very helpful.

 

The issue is relatively minor i guess, but it irks me nonetheless.

 

When i'm in a hooligan kinda mood, the bike launches like a frakking legend and you couldnt wipe the smile off my face with a hammer and chisel. Its just when i want to relax and ride it nice and smooth and slow that the problem creeps up. which is a shame really because 90% of the time thats how i ride (at the end of the day, my own survival has to take priority LOL)

 

With my old M400, i went with a KNN filter and aftermarket GPR pipes but that was not the solution. I'm not sure if the exhaust system is the cause, but if it is, it will be solved soon. I already ordered the exhaust kit i linked to in my earlier post and its currently on the way here and will be installed very soon (standby for a review)

 

When i spoke to Mike about this problem the impression I got from his reply was that it was inherent in all monsters and required a different style of throttling from the way I am used to to launch the bike properly at low rates of acceleration. Incidentally I did a lot of riding today to try and develop a technique for a slow launch and am improving in getting it moving off smoothly even if doing it slowly. Requires more than average throttle input initially and then a gradual throttle reduction once the bike hits the midrange in first gear. Will get the hang of it eventually I think.

 

Seraphx> Your reply interests me. I usually hate to mess with carbs as they are so bloody temperamental and absolutely a ***** to deal with when things are done wrong but could you provide specifics on what jet sizes you were using? I take it you were riding an M900 as well?

 

Motocafe> Daniel I spoke to Mike earlier asking him if he remembered what the front sprocket size is on the monster. The first time i asked him a while back he confidently told me it was a 14T but asking him again he seemed hesistant and thinks now that maybe its a 15T. If in fact it was a 15 it would explain a lot based on the stuff i've been reading on DML. Did you fit a 14T to it or is it running on the stock 15T?

 

Hello blackreplica,

 

on the contrary. I ride a '06 RS125. And I am able to answer your question because I do my own tuning. I never trust any mechs to do it as 95% of the mechs I meet can never give me satisfactory answer to my questions. Most of the mechs in Singapore rely too much on hand-me-down knowledge instead of actual technical know-how.

 

And since you're able to only feel a slight bogging at the revs, my opinion is that you're already in the ballpark figure for your jets. Which means, that you most probably just need to tweak with at most 2-3 jet sizes for the idle/pilot, and the main jet. As for the needle jet, I find that the top-most/leanest setting gives you the best results.

 

I suggest that before you start tuning, you should set your air/fuel mixture screw to a desired setting, like probably 2 turns? And then tweak your jets from there. This will give you the flexibility of richening or leaning out your mixture with the turn of a screw after you're satisfied with your jetting.

 

For example, if I know I am running rich and am running on a 160 main jet, I lean it off by changing it to one size smaller, i.e, 158 main jet. If it's STILL too rich, I'll drop it to 155 and so on. It's the safest way to make sure you're running rich enough while getting your tuning done.

 

It would also be a good idea to come up with your own chart to chart your progress and performance. Coz there WILL be a point where you start to go lean and the performance goes down. So what you want is the peak performance point in tuning. I have my own chart. If you're interested, perhaps I could give you some ideas on how to create a custom chart of your own?

[seraphx]

Hey all,

 

Just in case any of you guys are interested in getting belly pans and the sort for your monsters.

 

Here is a site that has all sorts of race fairings and stuff that you can get.

 

Just F.Y.I.

 

http://www.cruciata.com/scheda_eng.asp?idMarca=2&idModello=391&tipo=&fromSearch=1

[motocafe]

Motocafe> Daniel I spoke to Mike earlier asking him if he remembered what the front sprocket size is on the monster. The first time i asked him a while back he confidently told me it was a 14T but asking him again he seemed hesistant and thinks now that maybe its a 15T. If in fact it was a 15 it would explain a lot based on the stuff i've been reading on DML. Did you fit a 14T to it or is it running on the stock 15T?

 

Just open up the sprocket cover and count the number of teeth. Sorry, I can't remember also. The 'grey matter' ain't what it used to be.

 

heee that sounds like something I could do one day, which carbs did you have in mind? I believe there is a 39 and a 41 available from keihin (i might have got the numbers wrong tho). I'm thinking the smaller version so i don't mess up the low end. Those bloody keihins sure are expensive though. Time to add another mod to the wish list. Bloody ducatis...you just can't stop throwing money at them....its way too fun and addictive...good thing you did most of the hard work already haha

 

Yah, the expense was the limiting factor. But from what I read it will transform the monster into a different beast! I guess, 39mm would be more rideable (civil?) and 41mm would be wild?

 

FYI, working on the carb is a b*tch! You have to remove the airbox, battery, battery compartment, cables, etc. (30-45mins) before you even get to the carbs! Not to mention, the throttle cables are a pain to install. I did it about 6-7 times and frankly just gave it up and settled for the current setup. Perhaps that's why Minerva charge by the hour! Haha!

[technicolorhighway]

I'm really sorry to say this but I beg to differ...

 

No offense to anyone though.

 

The flat spot that you mention is actually caused by the tuning of your bike. Most of the M400s are carburator based. Hence, if you're running rich on either idle/pilot or needle jets, the overlap from the idle/pilot to the needle causes the flat spot, as the power is lost when the engine is unable to completely combust the mixture.

 

However, as soon as you pass the overlapping point, the needle jet is left in play and that is when a better mixture (slightly leaner as no overlapping of 2 jets) is obtained. You may also experience a flat spot on the higher revs when you gradually accelerate as there is also an overlapping point between your needle jet and your main jet.

 

Your mid-range or half-throttle is where the needle jet comes into play. When you are at WOT (Wide open throttle) or full throttle, that is when the needle jet is completely pulled out of your carb, with the slide, and the main jet is the one doing the whole job of controlling the air/fuel mixture.

 

Any carb based system will have this problem. As a matter of fact, you can ask any Aprilia RS125 rider if he experiences a flat spot at the 5k rpm mark and at the 8k rpm mark and I'd bet my entire paycheck, down to my last dollar, they would have it. I managed to actually tune it out of my bike just by dropping my jet sizes. It actually helped with my:

 

1) Fuel consumption. From 19km/l to 26km/l..

 

2) Power. Acceleration from standstill to top speed. From 21 seconds to 16 seconds. Top speed will have a slight variance. Mine actually increased by 6km/h.. from a 177km/h to 183km/h.

 

3) Response. You'll get much better response compared to running rich. Ask Randy, he has experienced the response of my bike first-hand. This does not mean you run lean. It just means that you're closer to the optimum efficiency setting for combustion.

 

4) Smoother power delivery. You'll get a smooth pickup at all rev ranges without the bogging at certain revs..

 

Hope this helps...

 

wow!sounds like you are describing a japanese made ducati.

 

cause i've changed to all that have been discussed above....

 

1)sprocket

2)k&n filter

3)FACTORY jet kit.(btw its for sale if any one wants to play with jet kit)

4)supertrapp exaust...with multiple `disc settings'

5) 3 most expirience duke mechanics.

6)countless tunings.

 

and no improvements

 

but when i make a full turnaround and put back and go all oem

 

exaust,carbs,sprockets...and work on my trottle/clutch play...it goes sweet.i wonder.

[technicolorhighway]

heee that sounds like something I could do one day, which carbs did you have in mind? I believe there is a 39 and a 41 available from keihin (i might have got the numbers wrong tho). I'm thinking the smaller version so i don't mess up the low end. Those bloody keihins sure are expensive though. Time to add another mod to the wish list. Bloody ducatis...you just can't stop throwing money at them....its way too fun and addictive...good thing you did most of the hard work already haha

 

like A WOMEN.

BTW don bother with carbs unless u want to race.

[JustRider]

FYI, working on the carb is a b*tch! You have to remove the airbox, battery, battery compartment, cables, etc. (30-45mins) before you even get to the carbs! Not to mention, the throttle cables are a pain to install. I did it about 6-7 times and frankly just gave it up and settled for the current setup. Perhaps that's why Minerva charge by the hour! Haha!

 

Your efforts are most commendable. Great ex-ride you had there.

 

Minerva does not charge by the hour. Fixed labour for different jobs.

[technicolorhighway]

Your efforts are most commendable. Great ex-ride you had there.

 

Minerva does not charge by the hour. Fixed labour for different jobs.

 

i once tried to also with the help and watchful eyes of the experts.manage just barely.they werent impressed.

[motocafe]

Your efforts are most commendable. Great ex-ride you had there.

 

Minerva does not charge by the hour. Fixed labour for different jobs.

 

Opps, my bad. Glad you clear that up. Goes to show that one shouldn't make assumptions, haha!

 

P.S. Perhaps I was thinking of Performance Motors.

[technicolorhighway]

Hello blackreplica,

 

on the contrary. I ride a '06 RS125. And I am able to answer your question because I do my own tuning. I never trust any mechs to do it as 95% of the mechs I meet can never give me satisfactory answer to my questions. Most of the mechs in Singapore rely too much on hand-me-down knowledge instead of actual technical know-how.

 

And since you're able to only feel a slight bogging at the revs, my opinion is that you're already in the ballpark figure for your jets. Which means, that you most probably just need to tweak with at most 2-3 jet sizes for the idle/pilot, and the main jet. As for the needle jet, I find that the top-most/leanest setting gives you the best results.

 

I suggest that before you start tuning, you should set your air/fuel mixture screw to a desired setting, like probably 2 turns? And then tweak your jets from there. This will give you the flexibility of richening or leaning out your mixture with the turn of a screw after you're satisfied with your jetting.

 

For example, if I know I am running rich and am running on a 160 main jet, I lean it off by changing it to one size smaller, i.e, 158 main jet. If it's STILL too rich, I'll drop it to 155 and so on. It's the safest way to make sure you're running rich enough while getting your tuning done.

 

It would also be a good idea to come up with your own chart to chart your progress and performance. Coz there WILL be a point where you start to go lean and the performance goes down. So what you want is the peak performance point in tuning. I have my own chart. If you're interested, perhaps I could give you some ideas on how to create a custom chart of your own?

 

 

We can base our tech know how form our previous bike to current.though i feel that comparing knowledge of yur 125 to a m900 is a bit far off.

 

there no doubt that all carbs work on the same principals but a single carbs from a (2 stroke)? and dual carbs from the 4 stroke engine require diff tunings methods.

 

back in the day of yam rs-100-tzr 125...those motoheads did evrything themselves...from over hauls to carb tunings then go on washing the bike in 1 day.

 

i even polish the carbs inner / outer wall with autosols!

 

Yes most mechanics knowledge are hands down like father to son and sometimes not much to learn yet we end up there asking for help.y bcause they actually know wat they are doin...

 

frankly..they are no different to a general practioners (doctors) they'll work on the yur assumption of wat is goin on.

 

what miricle they'll do only depend on how accurate yur self diagnose is.

and whether or not you want to spent $ & time on specialist.

[seraphx]

wow!sounds like you are describing a japanese made ducati.

 

cause i've changed to all that have been discussed above....

 

1)sprocket

2)k&n filter

3)FACTORY jet kit.(btw its for sale if any one wants to play with jet kit)

4)supertrapp exaust...with multiple `disc settings'

5) 3 most expirience duke mechanics.

6)countless tunings.

 

and no improvements

 

but when i make a full turnaround and put back and go all oem

 

exaust,carbs,sprockets...and work on my trottle/clutch play...it goes sweet.i wonder.

 

Uh.. I really didn't understand the part about the 'Japanese made Ducati'.. I actually tune all carburator based engines this way.. I tuned some boats, cars n bikes..

 

1) Sprockets do not affect your tuning in any way. Sprocket sizes affect acceleration/top speed. It's what gearing is all about. Sprockets do not directly affect combustion. Hence, the effect of sprocket changes are rather small. However, it is known that if you increase your acceleration, it does lean out your mixture slightly.

 

2) Different air filters limit the amount of air going into your engine differently. For example, stock air filters tend to be more dense and hence, letting lesser air into the engine. Less air, more fuel = rich. Changing it to a less dense air filter will allow more air to pass through. Hence, with changing your mixture, more air, same amount of fuel as before = slightly leaner.

 

3) Different jet kits are manufactured differently. Factory jet kits would be the best option to go for as they are most likely manufactured specifically for your bike. However, as all things automotive go, there are definitely some aftermarket jets around that may/may not perform better than factory kits. A 160 keihin main jet and a 160 mikuni main jet actually have a big difference to them. If we are using the keihin jets as a standard, then the mikuni main jet is about a size 150 main jet. Measured with a micrometer.

 

4) Exhaust systems help your bike breathe better. It allows exhaust gases to exit faster, while still retaining it's back-pressure for optimum combustion. Hence, the louder noise from a performance exhaust as compared to stock. Different exhaust manufacturers have different exhaust stomach designs. Hence, tunings will vary for a bike that has different exhaust systems.

 

5) Now this is a topic I am very afraid to touch on as I have offended tonnes of people already. Since this is a open forum, I will speak freely and hope that no one takes offense. There are many mechanics in Singapore who claim to be experienced and knows a lot about a particular bike as they have been working on it for many years. However, this experience does not constitute to proper know-how. For example, you may be doing something to a bike but have been doing it wrong for all the years you've been doing it. I know of a mech that has been working on Aprilias for at least 10 years and still doesn't know what he is doing. He can top up the gear oil to 800cc, when the gearbox actually prints a large 600cc on the side. You question him about it and he says that he's been doing it to ALL the Aprilias that he has serviced for all these years and nothing has happened. And claims that it's actually better for the bike! So there, experience, is not enough to convince me that a mechanic is actually good at what he does.

 

6) This I understand your frustration. But you will also have to know, that tunings are not a one time off thing. To get a bike tuned properly, it takes months of effort. Different riding styles lead to different tuning settings. If a mech can tell you that you only need to tune once, then he really doesn't know what he is talking about. Carburator based tuning is actually very dependant on outside factors. Things that can affect your tuning include,

 

a) air intake volume

b) air intake temperature

c) type of fuel used (different octane ratings)

d) temperature of spark from sparkplug

e) humidity levels

f) amount of exhaust back-pressure

 

So I totally understand your pain.. As I am still going through this phase myself...

 

One easy way to solve this problem though, is to totally run very rich. This takes away the sudden and explosive combustion that comes from precise tuning. When you run very rich, the bogging is not noticeable as the engine is unable to completely combust the mixture at ANY point of the throttle. Hence, giving the illusion of a smooth power delivery.

 

Just my 2 cents worth....

[seraphx]

We can base our tech know how form our previous bike to current.though i feel that comparing knowledge of yur 125 to a m900 is a bit far off.

 

there no doubt that all carbs work on the same principals but a single carbs from a (2 stroke)? and dual carbs from the 4 stroke engine require diff tunings methods.

 

back in the day of yam rs-100-tzr 125...those motoheads did evrything themselves...from over hauls to carb tunings then go on washing the bike in 1 day.

 

i even polish the carbs inner / outer wall with autosols!

 

Yes most mechanics knowledge are hands down like father to son and sometimes not much to learn yet we end up there asking for help.y bcause they actually know wat they are doin...

 

frankly..they are no different to a general practioners (doctors) they'll work on the yur assumption of wat is goin on.

 

what miricle they'll do only depend on how accurate yur self diagnose is.

and whether or not you want to spent $ & time on specialist.

 

LOL..

 

I feel as if we are in a academic debate.. =p

 

Like I mentioned in my previous post, I have tuned boats, cars, and some bikes. Boats can have 2 engines these are a ***** to tune. I have tuned Dodge Chargers, RX7s, CRXs, '86 Corollas, etc.. Bikes, are similar. It really doesn't matter if it is 2-stroke or 4, 1 carb or 6... You just have to know what you are doing.

 

Although I really don't understand why some people like to polish their carbs. I'm still trying to find out. Perhaps you could explain this to me when we next meet! It would be nice to learn something from you!

 

GPs actually listen to what you tell them, match it to the symptoms that they have learned about, and then give you a diagnosis of what they think it might be. Hence, the inaccuracy as some patients do not fully disclose their symptoms. If you have a sore throat, fever, and maybe dry lips, the doctor may just diagnose this as the common flu virus. However, if you told him that you have wet stools as well, then it becomes a totally different issue. It becomes food poisoning. Accuracy of our data is of utmost importance when it comes to maintaining our machines and bodies. Doctors don't assume. Mechanics shouldn't either. Mechanics are doctors that work on machines.

[technicolorhighway]

LOL..

 

I feel as if we are in a academic debate.. =p

 

Like I mentioned in my previous post, I have tuned boats, cars, and some bikes. Boats can have 2 engines these are a ***** to tune. I have tuned Dodge Chargers, RX7s, CRXs, '86 Corollas, etc.. Bikes, are similar. It really doesn't matter if it is 2-stroke or 4, 1 carb or 6... You just have to know what you are doing.

 

Although I really don't understand why some people like to polish their carbs. I'm still trying to find out. Perhaps you could explain this to me when we next meet! It would be nice to learn something from you!

 

GPs actually listen to what you tell them, match it to the symptoms that they have learned about, and then give you a diagnosis of what they think it might be. Hence, the inaccuracy as some patients do not fully disclose their symptoms. If you have a sore throat, fever, and maybe dry lips, the doctor may just diagnose this as the common flu virus. However, if you told him that you have wet stools as well, then it becomes a totally different issue. It becomes food poisoning. Accuracy of our data is of utmost importance when it comes to maintaining our machines and bodies. Doctors don't assume. Mechanics shouldn't either. Mechanics are doctors that work on machines.

 

Nah!not even close to a school yard fight.jus friendly poking of wat you have to say.

i would really like to see yur duke.just by reading wat you worked with bfore.in your hand must be the smoothest ducati in sg.free from any inperfecttion it is famous for jus like japanese bikes.(plug and play)

 

Back then @ 16,don know y ppl polish the carbs.all we know its jus better compared to jus bathing it in petrol.there where obvious stains that cannot be clean by petrol alone (could be rust i'll never know)but after whipping out he autosol.presto...gone.

 

What ever good or bad i expireince was by trial and error both from mechanics and other bikers.so forgive me poking it too much of you.

 

learning something new everyday is wat i like.

 

 

Since we are in the topic of learning.

 

by batt + ve lead connector melts regulary hence the constant buying of new ones.

 

1) check whether batt is overheating perhaps?done...voltage is in the good numbers.

 

2)regulator/rectifier check...same thing.

 

3)alernator check?works jus fine.

 

any idea wat it could be?

[seraphx]

Nah!not even close to a school yard fight.jus friendly poking of wat you have to say.

i would really like to see yur duke.just by reading wat you worked with bfore.in your hand must be the smoothest ducati in sg.free from any inperfecttion it is famous for jus like japanese bikes.(plug and play)

 

Back then @ 16,don know y ppl polish the carbs.all we know its jus better compared to jus bathing it in petrol.there where obvious stains that cannot be clean by petrol alone (could be rust i'll never know)but after whipping out he autosol.presto...gone.

 

What ever good or bad i expireince was by trial and error both from mechanics and other bikers.so forgive me poking it too much of you.

 

learning something new everyday is wat i like.

 

 

Since we are in the topic of learning.

 

by batt + ve lead connector melts regulary hence the constant buying of new ones.

 

1) check whether batt is overheating perhaps?done...voltage is in the good numbers.

 

2)regulator/rectifier check...same thing.

 

3)alernator check?works jus fine.

 

any idea wat it could be?

 

Ohk, I didn't really catch what you wrote but I'm guessing that your positive lead on your battery melts often.

 

Could be due to a few reasons. I doubt that the battery is overheating as battery cells just store and discharge energy. The voltage being in good numbers shows that your battery is actually in good condition.

 

Regulators regulate the amount of current that is drawn from the battery by whatever that requires power. Hence, that too is out of the question as it has nothing to do with the battery. The rectifier/alternator recharges your battery through your engine output, and since your voltage levels are fine, I would think that your rectifier/alternator is fine as well.

 

If I had to hazard a guess, it would be that the resistance of the cables you are using are a little high. For example, if you connected a battery to a copper wire and the same battery to a gold wire. The conductivity on the copper wire is a little lesser than the gold wire. And the electrical loss in the copper wire, is actually given off in the form of heat. Maybe you'd like to check the resistance of the cable you are using, and if the resistance value is less than 1ohm?

 

Another thing to check is to REALLY make sure that your regulator is really regulating the power outputs from the battery and not drawing more power from the battery. You could take reference points such as the voltage from the positive lead to ground (GND), the positive lead of the regulator to GND, and the negative lead of the regulator to GND. This way, you can see how much the battery is actually putting out, how much loss there is through the cable and if it fluctuates, and lastly, if the regulator is regulating your power output or just drawing more power.

 

Though another guess, but very unlikely, would be that the acid in the battery is leaking and slowly eating into the insulation of the cables that you bought.

 

And the final reason that I can think of, though again unlikely, is that perhaps, something else that is near your battery, is dissipating its heat into the cable, melting the insulation. Could be something as simple as a metal plate that heats up when you're riding, and that plate may be touching the cable insulation.

 

Hope this helps?

[technicolorhighway]

Ohk, I didn't really catch what you wrote but I'm guessing that your positive lead on your battery melts often.

 

Could be due to a few reasons. I doubt that the battery is overheating as battery cells just store and discharge energy. The voltage being in good numbers shows that your battery is actually in good condition.

 

The batt's that ive been using is the OEM ones.The part that has melted is not the + ve wire but the female end lead that hold down the + ve wire.when it melts,only the screw/nut is left with the + ve wire still ok.

 

Regulators regulate the amount of current that is drawn from the battery by whatever that requires power. Hence, that too is out of the question as it has nothing to do with the battery. The rectifier/alternator recharges your battery through your engine output, and since your voltage levels are fine, I would think that your rectifier/alternator is fine as well.

 

Syntoms of recgulator failing is overheating of the batt,lights dimming only until a certain rev is put into it.Occassionally the bulb `BLOWS'

Mine on the otherhand dont light up until movement then the sysntoms mention above never occurs.I took the liberty of replacing to a new reg/recf as a lazy solution but to no avail the sysntoms mentioned re-occurs.

 

If I had to hazard a guess, it would be that the resistance of the cables you are using are a little high. For example, if you connected a battery to a copper wire and the same battery to a gold wire. The conductivity on the copper wire is a little lesser than the gold wire. And the electrical loss in the copper wire, is actually given off in the form of heat. Maybe you'd like to check the resistance of the cable you are using, and if the resistance value is less than 1ohm?

 

Another thing to check is to REALLY make sure that your regulator is really regulating the power outputs from the battery and not drawing more power from the battery. You could take reference points such as the voltage from the positive lead to ground (GND), the positive lead of the regulator to GND, and the negative lead of the regulator to GND. This way, you can see how much the battery is actually putting out, how much loss there is through the cable and if it fluctuates, and lastly, if the regulator is regulating your power output or just drawing more power.

 

Though another guess, but very unlikely, would be that the acid in the battery is leaking and slowly eating into the insulation of the cables that you bought.

 

And the final reason that I can think of, though again unlikely, is that perhaps, something else that is near your battery, is dissipating its heat into the cable, melting the insulation. Could be something as simple as a metal plate that heats up when you're riding, and that plate may be touching the cable insulation.

 

Hope this helps?

 

im at my 3rd battery in 6 mths.i'm now trying a maintain free one.cross fingers

oh yes,im considering the possiblity of re-wiring the main harness.After all it is 15 yrs old.

Any experts out there?

[seraphx]

im at my 3rd battery in 6 mths.i'm now trying a maintain free one.cross fingers

oh yes,im considering the possiblity of re-wiring the main harness.After all it is 15 yrs old.

Any experts out there?

 

Hmmz, I'm sorry I misunderstood the issue that you brought up. I had the impression that it was the wire the whole time.

 

If your battery lead actually melts down, you have a serious but rather interesting issue on hand.

 

Honestly, I really can't think of anything that could possibly cause the battery lead to melt. Do let me know if you find out!