CB400 S4 vs XJR400 - which is better?

[rayhunter]

Hehehe... getting my Super 4 tomorrow. So excited.

 

enjoy yr ride!!

[s4dreamer]

I'm a Mechanical Engineer, and very interested in engines, so I read up about VTEC many years before. It's really not about the electronics. It's the Valve Timing, and that's the VT part of VTEC. EC stands for Electronic Control or something.

 

For 4-stroke engines, there are 4 strokes (duh!): 1. Intake (piston down, suck in petrol+air); 2: Compression (piston up); 3. Ignition (spark fired, piston pushed down, also called Power Stroke); 4. Exhaust (piston up, push exhaust out).

 

For all 4-stroke engines, at higher RPMs, all strokes take place faster. But fuel-air can only move so fast, and burn so fast. Result is, petrol has lesser time to get sucked in and so less get sucked in, and also lesser time to burn fully before being exhausted. So engines lose power, or unable to go to higher rpms.

 

But with VTEC, for motorbikes at least, the engine switches from a 2-valve (1 intake, 1 exhaust) to 4 valves once it reaches a certain high RPM (6-7k). This enables the engine to suck in more air in that short time (like when a swimmer gasps for air with a wide open mouth before plunging back into the water), and exhaust all the air too. (I think I read somewhere that the time of the spark firing is also slightly earlier to enable more complete combustion). Of course, fuel consumption increases.

 

Turbo, VTEC, fuel-injection etc are all ways of increasing the power. But done differently. Turbo pre-compresses the fuel-air, so there's actually MORE fuel-air pushed in at Intake. Fuel Injection injects the fuel directly between Intake and Compression, so the Intake only takes in air without the fuel, resulting in more fuel-air at Compression.

 

Sorry ah, but can't help going into so much detail about something I'm so passionate about - ENGINES!!

 

Hehehe... getting my Super 4 tomorrow. So excited.

 

I am very sure you will enjoy your ride! Super 4 is a good bike to ride on!

[Stardust83]

 

Hehehe... getting my Super 4 tomorrow. So excited.

 

Wow...good for u...U won't regret getting a S4 !

[Ah_Pet]

XJR has Ohlin suspensions as a standard.

 

but i also heard come with OEM ohlin caplier rite? correct mi if wrong.

[dreco]

XJR has Ohlin suspensions as a standard.

 

but i also heard come with OEM ohlin caplier rite? correct mi if wrong.

 

wrong its got brembo brake systems.

 

I'm a Mechanical Engineer, and very interested in engines, so I read up about VTEC many years before. It's really not about the electronics. It's the Valve Timing, and that's the VT part of VTEC. EC stands for Electronic Control or something.

 

For 4-stroke engines, there are 4 strokes (duh!): 1. Intake (piston down, suck in petrol+air); 2: Compression (piston up); 3. Ignition (spark fired, piston pushed down, also called Power Stroke); 4. Exhaust (piston up, push exhaust out).

 

For all 4-stroke engines, at higher RPMs, all strokes take place faster. But fuel-air can only move so fast, and burn so fast. Result is, petrol has lesser time to get sucked in and so less get sucked in, and also lesser time to burn fully before being exhausted. So engines lose power, or unable to go to higher rpms.

 

But with VTEC, for motorbikes at least, the engine switches from a 2-valve (1 intake, 1 exhaust) to 4 valves once it reaches a certain high RPM (6-7k). This enables the engine to suck in more air in that short time (like when a swimmer gasps for air with a wide open mouth before plunging back into the water), and exhaust all the air too. (I think I read somewhere that the time of the spark firing is also slightly earlier to enable more complete combustion). Of course, fuel consumption increases.

 

Turbo, VTEC, fuel-injection etc are all ways of increasing the power. But done differently. Turbo pre-compresses the fuel-air, so there's actually MORE fuel-air pushed in at Intake. Fuel Injection injects the fuel directly between Intake and Compression, so the Intake only takes in air without the fuel, resulting in more fuel-air at Compression.

 

Sorry ah, but can't help going into so much detail about something I'm so passionate about - ENGINES!!

 

Hehehe... getting my Super 4 tomorrow. So excited.

 

Yes i was wrong on the vtec as 2nd brains fo the bike..but....,vtec is electrically controlled as explained Valve Technology and lift Electronically Controlled.hehe...this techno gadget will activate a finger at the valve which syncronises 2 valves to open at any 1 time longer. but as mechanical engineer you forgot that there is no point of more valves opening IF combustion is still same in size which is 399cc..pardon me because i am a precision engineer and has even been there in a company building drive shafts for HONDA cars Japan based..

 

But just for the fun of it and if u check this vtec technology must be attached to the cdi because the rpm censor will send signal to cdi for vtec to activate. Eventually i have tried riding s4 and when the so called vtec opens up its no different to my xjr when its valves open fully too..like i said no point got vtec if still same exeleration like xjr but when i tried my dads suzuki bandit 400 the top reached 220 like nothing..

 

sooo it still comes to point of how u choose your bike..

[dreco]

http://www.motorbikes.be/en/compare/3238/5349/

 

this was the product of comparison through international network and this is from the previous thread s4 vs xjr4 in naked bikes forum.

 

[Honda_fan]

This equation is simple ppl

 

its true that s4 resale value is high compared to xjr4..BUT.....

riding in singapore roads for those just looking for transport xjr is cheaper when it comes to service. firstly EO is 2 ltrs instead of s4 3 ltrs ,air/oil cooled no need coolant ,and tank is 20ltrs..xjr is much more heavier but but it does not compromise on performance.xjr will run good as long as u got a good tune of the carb good eo..

 

the only difference is Vtec.

Now let me explain a lil abt vtec..it does not improve performance but may give a smoother ride..if yall actually check this vtec thingy also is available in honda cars but its actually something like additional brain for the vehicle giving smooth gear shift ,controlled electrical discharge and so on.and also the new revo abs is also tapped at ecu thru vtec..BUT 1 Minor power glitch will damage the ecu.

 

Like the XJR if you get a new one and get to have the bike tuned to your personal riding style rest assured no problems will arise.Parts is cheap if u get from LAB.and ah boy will take in orders for xjrers not to worry. Y its not much otr is because the first batch of xjr in 95-96 can only do 170 top speed but now i have prooved n tried 197kmh no problems..and mine is stock..Just make sure the bike doctor u send your bike to has passion to his job..

 

If you r gettin a second hand xjr pls do ask xjr club members for help coz gettin to pay a high price for it really sucks..if only everyone rides an xjr ofcoz you will get parts as easy as s4 everywhere..

 

but with all do respect do get something u r really confortable with..

 

Hey bro, wat is the diference btw oil cooled and liq cooled coolant. I oso experienced the S4 becomes very hot when i take class 2A from BBDC. Is it same for all bikes coz we r gng at slow speed thru the course. Do u noe any shop selling new or 2nd hand XJR. I was impressed when I saw the bike at CDC, wer i take my 2B. Please help..

[Light_Emotion]

wrong its got brembo brake systems.

 

 

 

Yes i was wrong on the vtec as 2nd brains fo the bike..but....,vtec is electrically controlled as explained Valve Technology and lift Electronically Controlled.hehe...this techno gadget will activate a finger at the valve which syncronises 2 valves to open at any 1 time longer. but as mechanical engineer you forgot that there is no point of more valves opening IF combustion is still same in size which is 399cc..pardon me because i am a precision engineer and has even been there in a company building drive shafts for HONDA cars Japan based..

 

But just for the fun of it and if u check this vtec technology must be attached to the cdi because the rpm censor will send signal to cdi for vtec to activate. Eventually i have tried riding s4 and when the so called vtec opens up its no different to my xjr when its valves open fully too..like i said no point got vtec if still same exeleration like xjr but when i tried my dads suzuki bandit 400 the top reached 220 like nothing..

 

sooo it still comes to point of how u choose your bike..

 

Hmm to mi Super Vtec are cheapest Vtec that Honda fitted that doesnt do any justice to the engine power nor the FC......

To make more horses.....You need higher lift at high rpm......In fact the Vtec series doesnt seem to be more frugal or more power...than its non vtec siblings....

Vtec on cars uses high speed cam that changes cam profile to improve valves lift and thus more air...more power.....Of course draw back is needed more fuel....More rev more bhp...

 

If this Vtec is so good then H should placed it into the CBR series......

Just another hype in engine technology that have nothing to shout about......

No offense to Vtec rider as I have 2 super 4 previously as well.....One VER S and Spec 2..

If it is not good I wont brought 2....ahhahaha

[Light_Emotion]

I'm a Mechanical Engineer, and very interested in engines, so I read up about VTEC many years before. It's really not about the electronics. It's the Valve Timing, and that's the VT part of VTEC. EC stands for Electronic Control or something.

 

 

 

But with VTEC, for motorbikes at least, the engine switches from a 2-valve (1 intake, 1 exhaust) to 4 valves once it reaches a certain high RPM (6-7k). This enables the engine to suck in more air in that short time (like when a swimmer gasps for air with a wide open mouth before plunging back into the water), and exhaust all the air too. (I think I read somewhere that the time of the spark firing is also slightly earlier to enable more complete combustion). Of course, fuel consumption increases.

 

 

 

Hehehe... getting my Super 4 tomorrow. So excited.

 

In some ways you are correct....But most inline 4 400cc have 16 V enable....So what you explained is all 400cc makes almost the same top end......

 

This Version of Vtec helps to create more torque at low/mid rpm......By nature the 8 V engine excel in low/mid rpm...So it actually combines both....

 

The above mentioned is the advantage that all 400cc inline 4 16V engine has now...

[dreco]

Hey bro, wat is the diference btw oil cooled and liq cooled coolant. I oso experienced the S4 becomes very hot when i take class 2A from BBDC. Is it same for all bikes coz we r gng at slow speed thru the course. Do u noe any shop selling new or 2nd hand XJR. I was impressed when I saw the bike at CDC, wer i take my 2B. Please help..

yup heating is due to slow riding..

difference of oil cool & liquid cool varies in a big way

 

oil/air cool bikes do not have overheating problems..oil cool means cooled off by means of engine oil used by goin thru oilcooler(aka radiator)

 

water cooled bikes uses coolant..like my previous experience with my gilera,engine shuts off once temperature reach red mark(overheat) and when in long traffic queue will damage the pump rod.luckyli overhaul is cheap...

 

xjr can find within this forum.BUtttt...besure dont get cheated of payin above 4-5k for 2nd hand fw-fz plate...go thru xjr club forum contact beer1860..he sellin his bike and for all i know his bike has been in alot of tender lovin care..

 

gd luck

[dreco]

Hmm to mi Super Vtec are cheapest Vtec that Honda fitted that doesnt do any justice to the engine power nor the FC......

To make more horses.....You need higher lift at high rpm......In fact the Vtec series doesnt seem to be more frugal or more power...than its non vtec siblings....

Vtec on cars uses high speed cam that changes cam profile to improve valves lift and thus more air...more power.....Of course draw back is needed more fuel....More rev more bhp...

 

If this Vtec is so good then H should placed it into the CBR series......

Just another hype in engine technology that have nothing to shout about......

No offense to Vtec rider as I have 2 super 4 previously as

well.....One VER S and Spec 2..

If it is not good I wont brought 2....ahhahaha

 

 

cbr series cant compare to rvf series...amongst all engines V-Twin is still the best..V-twin got greater pick up & very strong for mountain climbing.

but v-twin is not superior to bmw boxer engine.ontop of its power its fuel saving savvy..if u mountain climbing freak/sports biker RVF is better

[loufu]

cbr series cant compare to rvf series...amongst all engines V-Twin is still the best..V-twin got greater pick up & very strong for mountain climbing.

but v-twin is not superior to bmw boxer engine.ontop of its power its fuel saving savvy..if u mountain climbing freak/sports biker RVF is better

 

best? depends on which area oso wat... if u are the best in spd/acceleration/torque etc, u might be the last in FC/maintenance/reliability etc..

Edited March 12, 2009 by loufu

[Light_Emotion]

cbr series cant compare to rvf series...amongst all engines V-Twin is still the best..V-twin got greater pick up & very strong for mountain climbing.

but v-twin is not superior to bmw boxer engine.ontop of its power its fuel saving savvy..if u mountain climbing freak/sports biker RVF is better

 

Now we are debating about valve technologies....Engine configuration are different things....

Because of the big bang...That y most scamber uses single piston that uses single bang to allows rear tire to recover and dig into the loose sand....

 

V twin have big power pulse that aid torque in low/mid.....But because of big piston...Most V twin dont have high rev.....Remember torque x rpm = BHP....Same cc compare to inline 4.....

Inline 4 have higher bhp...

Think of 1098/1198 needed additional 1-200 cc to match the bhp difference on the IL4 of the jap 1000cc super bike bhp....

 

Now into V4... Moto GP aside.... the street version V4 other than a narrower engine I dont see any good on it....

The most popular RVF....Do 400cc need a narrower engine???

i dont think so as most 400cc IL4 engine are narrow enough...

 

Not to mention V engine do have 2 set of cams shafts,2 banks of carbs, set of top engine gasket and etc....

Which in term cost more if you need to top overhaul the bike.....

[dreco]

Now we are debating about valve technologies....Engine configuration are different things....

Because of the big bang...That y most scamber uses single piston that uses single bang to allows rear tire to recover and dig into the loose sand....

 

V twin have big power pulse that aid torque in low/mid.....But because of big piston...Most V twin dont have high rev.....Remember torque x rpm = BHP....Same cc compare to inline 4.....

Inline 4 have higher bhp...

Think of 1098/1198 needed additional 1-200 cc to match the bhp difference on the IL4 of the jap 1000cc super bike bhp....

 

Now into V4... Moto GP aside.... the street version V4 other than a narrower engine I dont see any good on it....

The most popular RVF....Do 400cc need a narrower engine???

i dont think so as most 400cc IL4 engine are narrow enough...

 

Not to mention V engine do have 2 set of cams shafts,2 banks of carbs, set of top engine gasket and etc....

Which in term cost more if you need to top overhaul the bike.....

 

actually my words meant like riding up genting with 400cc..eg lah...reliability V-twin..(aside from FI series)its easier to explore valve tecnology den to get true answers comparing bore & stroke which explains torque n rpm..i get confused eventually..which makes me wanna create an engine that and explain to myself...hahaha..ive come to a point where brain dont digest theory...

but goin back to topic still comparing Honds S4 to Yamaha Xjr..but cant push away the thot of suzuki's(bandit) engine reliability.den again in moto gp its still either a ducati or yamaha..

 

soo best is to conclude its not the bike coozen...its always been the rider..

[Light_Emotion]

That's explain the popularity of the suzuki SV series in UK.

I myself had a SV 650 previously..

Comparing to IL4 the engine is a notch below. The power pulse can be felt through the whole bike which might not be everyone's liking....

Some of them might think is the character of the bike...Think DUCAtI monsters...

[Darkness19]

S4

[MonoWorld]

suzuki's(bandit) engine reliability

so suzuki engine reliable?

[Felix2665]

Just wondering is Kawasaki Zephyr X in Sin ?