Aprilia Riders

Bullmoo · August 25, 2010

My rpm needle seems to be working fine, its only the digital speed readings tats stuck on zero.

hahahah. bro, we got the same luck, just the opp of yours, my rpm not working but still able to see how fast im going.

Bullmoo · August 25, 2010

$400. Hope you pass your 2B soon.

I got my at $800. age 26

Bullmoo · August 25, 2010

$400. Hope you pass your 2B soon.

Ahh... the ever changing 'variable' price in sg.

My friend got it replaced for $120.

Ah seng quoted me $115 two hours ago at 37 Motoring..

Mine - analog RPM meter works fine but my digital speedometer is 'stationary' at 0 all the way. I guess its a common problem huh..

Bullmoo - yep, i ride the new RS125.

I always wave at other RS125ians on the road.

Yep!! hi aprilian!! I check my, gotta change the whole hell thing. $800 new, $300 2nd hand. pocket burn again.

Sub Zero · August 25, 2010

Bro Shan.. So do u have a airbox to sell mi?
Lol..
I dunno bout the mech la..
I but trust him as quite well known to ppl over here..
I jus got the 125 last 2 weeks..
Jus wanna try out fairings bike as I sold my plastic bike already..
Lol..
Still new in this bike..
Trying to fix all the problems..

I have.. $100 for an airbox from an 09 model.

Sub Zero · August 25, 2010

yo...... today jus got my bike from my spray..... but the mech told me my water pump spoil.... need to overhaul.... i was told aprilia water pump is in the engine ..... is it true???
feel like the mech wan to chop my head.....

The only problem that i can see is coolant leaking .....

You know how that mech is and you still continue to patronise him?

The water pump is at the same side as the clutch. You dont need to do a complete overhaul or down engine to change it. Simply remove the whole clutch housing.

jackwr · August 25, 2010

Bro sub zero..

Forget to mention I'm riding the y2k version..

Not the facelift model..

But can the 09 air box fit the old model ones?

Feelicks · August 25, 2010

DIY Session
1. Lawrence
2. Lester
3. Matthew
4. Koon
5. Felix

Makan Session @ Pasir Panjang Food Centre
1. Lawrence
2. Kalyan
3. Lester
4. Matthew
5. Felix

lacrimosae · August 25, 2010

elevened,

A quick response to your queries before I fly off tonight, something concise regarding the pod filter versus airbox decision. (and just in case I don't return alive, Viknesh will fill in the blanks as he knows quite as much as I do)

The airbox works on the principle of resonance.

Motorcycles have had air boxes holding their air filters for decades. However, in the last couple of decades the purpose of these air boxes has changed quite dramatically.

Originally the air box was just there to keep flying dirt, rain, and bugs from directly hitting the air cleaner. They were simply an attempt to keep the air cleaner a little cleaner a little longer.

In the '70s, the US government started making noise regulations tighter. At some point, the manufacturers realized that the noise from the air intake was part of their problem. They started to look for ways to muffle not only the exhaust, but the intake roar too. Sound waves are pressure pulses in the air. Pistons pull in air on their intake stroke, creating a low pressure pulse in the air box. Then on the compression, power, and exhaust strokes the intake valve is closed and the air box is free to return to atmospheric pressure. These alternating low pressure and normal pressure pulses are sound waves. The manufacturers needed some way to dampen them out.

Your exhaust mufflers are made of a series of open chambers connected to each other by tubes. The exhaust pressure pulses get caught in the chambers and bounce around in them, then have to leak out relatively slowly through the tubes. The math that governs mufflers can also be applied to air boxes: you need a big chamber to hold a bunch of air, and an inlet tube to let air in at a controlled rate.

The air in a box is compressible, so a box is the acoustic analog of a capacitor or spring. Air has mass - about 1kg / cubic meter, about 2 pounds per cubic yard. In a tube, the air moves back and forth as a slug, as long as the frequency of the movement is small compared to (tube length / speed of sound). So, at low frequencies a tube is a mass term. Since the speed of sound is about 1000 feet per second, a foot long tube is equivalent to 1 khz. 10,000 rpm is 160 pulses per second on a V-Twin, so "low frequency" clearly applies on an air box for any snorkel shorter than about 6 feet long. A wire screen is the acoustic analog of a resistor. It slows air motion, converting the energy into heat. The combination of a box and tube is a system with a resonance. Exactly as a child's swing has a resonant frequency, exactly as a ported speaker enclosure has a resonant frequency, so does your air box.

A system at resonance is nearly perfect - there are small frictional losses in any system, but at resonance these are the only losses. Imagine pushing a child on a swing - it takes very little energy to keep her going at the natural frequency of the swing, just a little push each swing is enough. The only thing slowing her down is air resistance and a little friction in the chains. So at resonance, air flows through a tuned air box almost without resistance. This is as close as we can get to a superconductor of air.

A modern engine with valve overlap will naturally have a dip in the torque at about a third to a half the red line rpm. If the air box is tuned to have minimum resistance to air flow at this rpm, the dip in the torque curve will be partially filled in by the ease of pulling air into the engine.

So, your air box is most likely designed to add horsepower in the mid-range. The air box will have little or no effect on peak hp.

Years ago, before airboxes were designed as resonant systems, it used to be popular to cut additional holes in the air box to allow more air flow for high rpm. This is no longer a good idea. Modern air boxes can flow much more air than the engine will ever use. Modern engines have throttle bodies or carburetors with throats that are typically about 45mm in diameter, about 16 sq.cm in area. The inlet snorkel to a modern air box will be roughly 300 to 800 sq.cm - much larger than the throttle body or carburetor throat. The idea that the snorkel makes for a significant impediment to air flow into the engine is questionable at best. Drilling holes to let in more air is exactly equivalent to drilling holes in your speaker cabinets to let out more sound. Removing the snorkel from your air box is the exact same thing as removing the port in your speakers, the tube that's carefully engineered to have just the right diameter and length to reinforce the bass on your speakers at low frequencies. By altering your air box in any significant fashion, you're most likely going to cost yourself three to five hp in the mid range, and gain nothing measurable at high rpms.

Now, for the math:

Here, from first principles we'll develop the theory of how an air box and an inlet tube form a coupled spring- mass system with a resonant frequency.

air box volume = V

inlet pipe = area * length = A * L

Air Mass = 1.25g / 1000 cc

Atmospheric Pressure = 104kg / cm sec2

PV = nkT (Ideal Gas Law)

If the air in the inlet tube moves X cm into the air box, then the volume of air inside the air box changes to:

V' = V + AX

Since Boltzman's constant and the air box volume don't change, that leaves only the temperature and the pressure. The gamma for air is 1.4, so

T' / T = (V' / V)^.4

T' / T = (1 + AX/V)^.4

We'll presume AX/V is small, so (1 + AX/V)^.4 = 1 + .4AX/V

The number of atoms in the air box changes to n' = (1 + AX/V)n. So, the new pressure is:

P'V = (1+AX/V) nk (1+.4AX/V) T

P' = (1 + AX/V) (1 + .4AX/V) P

P' = (1 + 1.4 AX/V) P

Now we can find the spring constant of the air box, K:

Force = Pressure*Area = Kx

Kx = 1.4 AX/V * A * 104 kg cm / sec2

K = AA/V * 146 kg / sec2

The mass of air in the inlet tube is

M = AL * 1.25g / 1000

The resonant frequency w, in radians per second, of a spring-mass system is:

w = sqrt( K/M )

= sqrt( AA/V * 146 kg / sec2 * 1000 / 1.25g AL )

= sqrt( A/VL * 146*1000*1000 / 1.25 sec2 )

= 1000 sqrt( 116.5 A/VL ) / sec

The resonant frequency is w / 2pi, and the resonant rpm is 30 * number of cylinders * f. For a V-twin, rpm = 60 * f.

f = w / 2pi = 160 sqrt( 116.5 A / VL )

resonant rpm = 4775 sqrt( 116.5 A / VL ) (single cylinder)

resonant rpm = 9550 sqrt( 116.5 A / VL ) (V-twin)

resonant rpm = 19100 sqrt( 116.5 A / VL ) (4 cylinder)

To sum it all up, your bike performs identically at high revs with an airbox as it does with an altered air intake.

In my opinion, and based on my own experimenting over the past 7 years, I must conclude that running an airbox is best for street riding when your revs are at mid-range and your throttle position about 1/4 to 3/4.

Pod filters are harder to tune at low revs, but allow free-flowing air at high revs, making them good for track use, or if u ride on the street above 9,000 rpm all the time.

For a more detailed or layman explanation, do contact Subzero, or Viknesh. He is currently using a pod/cone filter.

Feelicks · August 25, 2010

dude... u shld start a sch

quikslvr · August 25, 2010

elevened,

A quick response to your queries before I fly off tonight, something concise regarding the pod filter versus airbox decision. (and just in case I don't return alive, Viknesh will fill in the blanks as he knows quite as much as I do)

The airbox works on the principle of resonance.

Motorcycles have had air boxes holding their air filters for decades. However, in the last couple of decades the purpose of these air boxes has changed quite dramatically.

Originally the air box was just there to keep flying dirt, rain, and bugs from directly hitting the air cleaner. They were simply an attempt to keep the air cleaner a little cleaner a little longer.

In the '70s, the US government started making noise regulations tighter. At some point, the manufacturers realized that the noise from the air intake was part of their problem. They started to look for ways to muffle not only the exhaust, but the intake roar too. Sound waves are pressure pulses in the air. Pistons pull in air on their intake stroke, creating a low pressure pulse in the air box. Then on the compression, power, and exhaust strokes the intake valve is closed and the air box is free to return to atmospheric pressure. These alternating low pressure and normal pressure pulses are sound waves. The manufacturers needed some way to dampen them out.

Your exhaust mufflers are made of a series of open chambers connected to each other by tubes. The exhaust pressure pulses get caught in the chambers and bounce around in them, then have to leak out relatively slowly through the tubes. The math that governs mufflers can also be applied to air boxes: you need a big chamber to hold a bunch of air, and an inlet tube to let air in at a controlled rate.

The air in a box is compressible, so a box is the acoustic analog of a capacitor or spring. Air has mass - about 1kg / cubic meter, about 2 pounds per cubic yard. In a tube, the air moves back and forth as a slug, as long as the frequency of the movement is small compared to (tube length / speed of sound). So, at low frequencies a tube is a mass term. Since the speed of sound is about 1000 feet per second, a foot long tube is equivalent to 1 khz. 10,000 rpm is 160 pulses per second on a V-Twin, so "low frequency" clearly applies on an air box for any snorkel shorter than about 6 feet long. A wire screen is the acoustic analog of a resistor. It slows air motion, converting the energy into heat. The combination of a box and tube is a system with a resonance. Exactly as a child's swing has a resonant frequency, exactly as a ported speaker enclosure has a resonant frequency, so does your air box.

A system at resonance is nearly perfect - there are small frictional losses in any system, but at resonance these are the only losses. Imagine pushing a child on a swing - it takes very little energy to keep her going at the natural frequency of the swing, just a little push each swing is enough. The only thing slowing her down is air resistance and a little friction in the chains. So at resonance, air flows through a tuned air box almost without resistance. This is as close as we can get to a superconductor of air.

A modern engine with valve overlap will naturally have a dip in the torque at about a third to a half the red line rpm. If the air box is tuned to have minimum resistance to air flow at this rpm, the dip in the torque curve will be partially filled in by the ease of pulling air into the engine.

So, your air box is most likely designed to add horsepower in the mid-range. The air box will have little or no effect on peak hp.

Years ago, before airboxes were designed as resonant systems, it used to be popular to cut additional holes in the air box to allow more air flow for high rpm. This is no longer a good idea. Modern air boxes can flow much more air than the engine will ever use. Modern engines have throttle bodies or carburetors with throats that are typically about 45mm in diameter, about 16 sq.cm in area. The inlet snorkel to a modern air box will be roughly 300 to 800 sq.cm - much larger than the throttle body or carburetor throat. The idea that the snorkel makes for a significant impediment to air flow into the engine is questionable at best. Drilling holes to let in more air is exactly equivalent to drilling holes in your speaker cabinets to let out more sound. Removing the snorkel from your air box is the exact same thing as removing the port in your speakers, the tube that's carefully engineered to have just the right diameter and length to reinforce the bass on your speakers at low frequencies. By altering your air box in any significant fashion, you're most likely going to cost yourself three to five hp in the mid range, and gain nothing measurable at high rpms.

Now, for the math:

Here, from first principles we'll develop the theory of how an air box and an inlet tube form a coupled spring- mass system with a resonant frequency.

air box volume = V

inlet pipe = area * length = A * L

Air Mass = 1.25g / 1000 cc

Atmospheric Pressure = 104kg / cm sec2

PV = nkT (Ideal Gas Law)

If the air in the inlet tube moves X cm into the air box, then the volume of air inside the air box changes to:

V' = V + AX

Since Boltzman's constant and the air box volume don't change, that leaves only the temperature and the pressure. The gamma for air is 1.4, so

T' / T = (V' / V)^.4

T' / T = (1 + AX/V)^.4

We'll presume AX/V is small, so (1 + AX/V)^.4 = 1 + .4AX/V

The number of atoms in the air box changes to n' = (1 + AX/V)n. So, the new pressure is:

P'V = (1+AX/V) nk (1+.4AX/V) T

P' = (1 + AX/V) (1 + .4AX/V) P

P' = (1 + 1.4 AX/V) P

Now we can find the spring constant of the air box, K:

Force = Pressure*Area = Kx

Kx = 1.4 AX/V * A * 104 kg cm / sec2

K = AA/V * 146 kg / sec2

The mass of air in the inlet tube is

M = AL * 1.25g / 1000

The resonant frequency w, in radians per second, of a spring-mass system is:

w = sqrt( K/M )
= sqrt( AA/V * 146 kg / sec2 * 1000 / 1.25g AL )
= sqrt( A/VL * 146*1000*1000 / 1.25 sec2 )
= 1000 sqrt( 116.5 A/VL ) / sec

The resonant frequency is w / 2pi, and the resonant rpm is 30 * number of cylinders * f. For a V-twin, rpm = 60 * f.

f = w / 2pi = 160 sqrt( 116.5 A / VL )

resonant rpm = 4775 sqrt( 116.5 A / VL ) (single cylinder)

resonant rpm = 9550 sqrt( 116.5 A / VL ) (V-twin)

resonant rpm = 19100 sqrt( 116.5 A / VL ) (4 cylinder)

To sum it all up, your bike performs identically at high revs with an airbox as it does with an altered air intake.

In my opinion, and based on my own experimenting over the past 7 years, I must conclude that running an airbox is best for street riding when your revs are at mid-range and your throttle position about 1/4 to 3/4.

Pod filters are harder to tune at low revs, but allow free-flowing air at high revs, making them good for track use, or if u ride on the street above 9,000 rpm all the time.

For a more detailed or layman explanation, do contact Subzero, or Viknesh. He is currently using a pod/cone filter.

My maths fail.I imagine u now as a Prof writing all that formula on a blackboard in a university lecture

Sub Zero · August 25, 2010

Bro sub zero..
Forget to mention I'm riding the y2k version..
Not the facelift model..
But can the 09 air box fit the old model ones?

Yes, it can fit. NO issues.

Sub Zero · August 25, 2010

Sorry Mr Lacriomsae,

While I concur with your theory, and it is relevant to my personal experiences with airbox and pod filter, I am not at the moment using a pod filter.

My advice would be remove airbox, no pod filter, and just run like that. Optimum power.

NO headache for any incompetent mech to fix.

Jiro · August 25, 2010

Anyone knows the shipping cost for apriliayorkshire? or aprilia genuine parts?

i dont know if its the same.

priller07 · August 25, 2010

Sorry Mr Lacriomsae,

My advice would be remove airbox, no pod filter, and just run like that. Optimum power.

NO headache for any incompetent mech to fix.

Dude, i ever did that u know.. Hahaha.. Bottom end like sh*t. Top end can feel some difference. Personal experience lah..

Icezstorm · August 26, 2010

Hey Guys, anyone here keen to get my RS250? The previous is ang ku guay, he has rebuild the bike from scratch. I am letting go for now, as this has been parked till flat for the 3rd time.

it starts well with 1 kick and is maintain and service by Bayi. Looking @ $3,500 neg. This is some other details of my bike

1996 RS250

9mths old BT090

Titanium nitrate front fork (purplish in colour)

Bitubo Rear Sub

Full arrow System (end can wrapped up to make it seem like original)

Single seat cowling

Red pole light + white bulbs

additional set of spare race fairing

Rewrapped both seats to anti slip

New owner just need to do a basic servicing and also change the chain. please PM me for more details or pics, Cheers. .

Edited August 27, 2010 by Icezstorm

priller07 · August 26, 2010

Where's Bayi located now bro? Last i checked he was at Eunos with Ah Huat.

jackwr · August 26, 2010

Bayi is located at glen motor..

At kallang industrial there..

Behind ah boy workshop..

darkiller22003 · August 26, 2010

You know how that mech is and you still continue to patronise him?

The water pump is at the same side as the clutch. You dont need to do a complete overhaul or down engine to change it. Simply remove the whole clutch housing.

THX for the information about the water pump, i did not ask them to overhaul my bike... tat is y i am here to ask about the problem..... but do u have any mech that can help me in this problem ??? (Without overhauling)

IZECUBEZ · August 26, 2010

Source: Aprilia.com

THE AIRBAG JACKET, PROTECTION WITH STYLE.

Aprilia presents a new safety garment with elegance and style to cater for the most discerning rider.

The Airbag jacket is a new, innovative and vital technical safety garment. The new jacket features an inflatable backrest offering complete neck, spine and sacrum area protection as well as a set of shoulder and elbow protectors, and comes with the style and livery of the Aprilia brand.

http://www.aprilia.com/userfiles/image/news/giacca_airbag/Aprilia%20Airbag_600a.jpg

The Airbag Jacket has been created in the interest of rider safety; it is a garment ensuring total protection of the parts of the body most at risk when riding a two-wheeler. In the event of an accident, the airbag incorporated in the back of the jacket activates and inflates in just 80-85 milliseconds to ensure instantaneous protection for the spine.

The Airbag Jackets by Aprilia is stylish, classy and sporty on the outside while concealing a simple and effective protection system within: a clip on the end of an elastic cable fastens the jacket to a belt (supplied together with the airbag system) attached to the motorcycle itself. If pulled forcefully - as would occur in the event of an accident - the cable activates a gas bottle contained in the back of the jacket. The CO2 released from the bottle fills the compartments in the garment, ensuring full protection for the rider in under a second.

Once the airbag system has been activated, the system may be recharged and the jacket used again. Once recharged, functionality of the back protection system is immediately restored and the rider may continue his or her journey.

The Airbag Jacket is the perfect solution for your safety.

Patented by MotoairbagÂ®, the airbag system used by the Piaggio Group is produced entirely in Italy and is the only system of its kind with EN1621-2:2003 certification when inflated.

The Aprilia Airbag Jacket is already available from Piaggio Group dealerships in black with red and grey details.

http://www.aprilia.com/userfiles/image/news/giacca_airbag/Aprilia%20Airbag_600b.jpg

http://www.aprilia.com/userfiles/image/news/giacca_airbag/Aprilia%20Airbag_600c.jpg

This is so screaming for a MASS ORDER!

Come to think about it, can double up as a overnight camping jacket! Hahahahahaha!

personified · August 27, 2010

Just met up with Larry of Personified. He's got a nice place there to chill. And he carries some products that may be of interest to some riders here.

I've already purchased a set of R&G Aero crash protectors. Quite a serious piece of kit to have. Its not just crash bungs, but is also teardrop-shaped for aerodynamics. Nice. VERY NICE.

Thanks Bro..and once u have it installed,post a pix please..I need it for my advertisers' board:thumb:

Sub Zero · August 27, 2010

Hey Guys, anyone here keen to get my RS250? The previous is ang ku guay, he has rebuild the bike from scratch. I am letting go for now, as this has been parked till flat for the 3rd time.

it starts well with 1 kick and is maintain and service by Bayi. Looking @ $3,500 neg. This is some other details of my bike

1996 RS250

9mths old BT090
Titanium nitrate front fork (purplish in colour)
Bitubo Rear Sub
Full arrow System (end can wrapped up to make it seem like original)
Single seat cowling
Red pole light + white bulbs
additional set of spare race fairing
Rewrapped both seats to anti slip

New owner just need to do a basic servicing and also change the chain. please PM me for more details or pics, Cheers. .

Previous owner is a friend of ours. He let go the bike just after a few months coz it was a lemon.

Sub Zero · August 27, 2010

THX for the information about the water pump, i did not ask them to overhaul my bike... tat is y i am here to ask about the problem..... but do u have any mech that can help me in this problem ??? (Without overhauling)

I suggest you look for David at Teck Thye. He's located along Braddell Road. Right at the end, where it meet serangoon road if i'm not wrong.

He gets the job done right. Also, if it's just your water pump seals that are leaking, I suggest you can get them from PJME yourself too.

blast3dGaL · August 27, 2010

Source: Aprilia.com

THE AIRBAG JACKET, PROTECTION WITH STYLE.

Aprilia presents a new safety garment with elegance and style to cater for the most discerning rider.
The Airbag jacket is a new, innovative and vital technical safety garment. The new jacket features an inflatable backrest offering complete neck, spine and sacrum area protection as well as a set of shoulder and elbow protectors, and comes with the style and livery of the Aprilia brand.
http://www.aprilia.com/userfiles/image/news/giacca_airbag/Aprilia%20Airbag_600a.jpg

The Airbag Jacket has been created in the interest of rider safety; it is a garment ensuring total protection of the parts of the body most at risk when riding a two-wheeler. In the event of an accident, the airbag incorporated in the back of the jacket activates and inflates in just 80-85 milliseconds to ensure instantaneous protection for the spine.

The Airbag Jackets by Aprilia is stylish, classy and sporty on the outside while concealing a simple and effective protection system within: a clip on the end of an elastic cable fastens the jacket to a belt (supplied together with the airbag system) attached to the motorcycle itself. If pulled forcefully - as would occur in the event of an accident - the cable activates a gas bottle contained in the back of the jacket. The CO2 released from the bottle fills the compartments in the garment, ensuring full protection for the rider in under a second.

Once the airbag system has been activated, the system may be recharged and the jacket used again. Once recharged, functionality of the back protection system is immediately restored and the rider may continue his or her journey.

The Airbag Jacket is the perfect solution for your safety.

Patented by MotoairbagÂ®, the airbag system used by the Piaggio Group is produced entirely in Italy and is the only system of its kind with EN1621-2:2003 certification when inflated.

The Aprilia Airbag Jacket is already available from Piaggio Group dealerships in black with red and grey details.
http://www.aprilia.com/userfiles/image/news/giacca_airbag/Aprilia%20Airbag_600b.jpg

http://www.aprilia.com/userfiles/image/news/giacca_airbag/Aprilia%20Airbag_600c.jpg

This is so screaming for a MASS ORDER!
Come to think about it, can double up as a overnight camping jacket! Hahahahahaha!

super nice.. i can imagine myself being me, forgetting to detach the clip when getting off my bike and get full blown, before it deflats itself to normal again..

Jiro · August 27, 2010

Previous owner is a friend of ours. He let go the bike just after a few months coz it was a lemon.

what do you mean by it was a lemon?

priller07 · August 27, 2010

Previous owner is a friend of ours. He let go the bike just after a few months coz it was a lemon.

It's the Oxydo one? Hahaha.. I think i know alrdy. Few days ago saw him near Auntie's shop.

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