Adding to the front should do just the opposite of what you want. Removing teeth from the front would do the same thing as adding to rear. I think your dealer is smoking crack.

 

Most people drop one in the front instead of increasing 2-3 in the rear so you can keep the same chain size. It's about the same result.



Don't care that's it's the first post !! What's the big deal with that anyway ?



Small things amuse small minds

 

+1



dropping teeth on the front functions like adding them on the rear.



*wonders if we can get into a debate concerning "wrapping the chain too tight" and other such things*

 

Why would anyone want better acceleration on a big, fast bike anyway? You're already at the wheelie limit until 4th gear... Dropping one from the front of a 600 maybe, but they're pretty close to the wheelie limit these days too... My 06 GSX-R600 will try to lift the front in 3rd if I hit a very slight bump in the track when I'm using full power... It won't quite do it, but it sure does get light.

Chango

 

Yeah that whole "wearing out the chain more quickly" debate is right up there with the "too slippery" oil debate.

 

unless you just heard the guy wrong, i would end your relationship with this particular motorbike shop.

 

Actually fewer teeth at the front would have the opposite effect. Adding teeth at the front would produce a 'higher' gear and reduce (slightly) accelleration. A small front sprocket will reduce chain life quite alot though, as the chain has to 'bend' more around a smaller sprocket. Mind you if you're going to wheelie on a 1400cc bike, I'm guessing chain life isn't a big concern.

 

Hey how do you like the 06 GSXR600 ?? From some of the reviews I've seen it's an awesome bike. I hear it pulls well very low in the powerband.

 

It's the ratio is the key..get on a bicycle

Do you have a bicycle lying around...If so go get on it and figure it out yours self. By increasing the number of teeth on the rear you are lower the gear. By increasing the number of teeth on the front you are raising the gear... Verify that by getting on a bicycle and increse the number of teeth on the rear i.e. shift the rear derailer to the inside... Peddaling gets eaiser right. especially when you accelerate...However the downside is when you need top end speed you won't have it . i.ke Pretend you are the engine when you get on your bicycle.

 

Well said

 

It's slippery slope you don't want go there Buz.

 

not really.

 

You should have paid better attention in math class.



Making the rear sprocket larger gives you lower gearing, which should improve acceleration. You can do this by adding 2 or 3 teeth to the rear or going DOWN 1 tooth on the front.



Most motorcycles have a front to rear ratio of "very approximately" 1 to 3.



Simple example: 15 front / 45 rear = 1/3.



Increasing the front sprocket would theoretically raise top-speed but diminish acceleration.

 

And, yes, if the guy at the shop really said what he said, he either suffered a brain fart, or has no business near anything mechanical.

 

wilro is correct. 1 tooth in the front = -3 in the rear. Adding 3 to the rear would be like subtracting one from the front.

 

Yeah, that is a little scary coming from a guy working at a bike shop!

 

Re: It's the ratio is the key..get on a bicycle

Should he make vroom vroom noises too?

 

OK, 6 one, half.5 dozen of another

 

Re: It's the ratio is the key..get on a bicycle

Gears are for p*ssies. Single-speed baby. But I'm sure the Schwinn Varsity gets old school street cred.

 

It's a kind of folk myth that lowering the overall gear ratios (by increasing teeth on the rear or decreasing the front) will increase accleration significantly. If you look at a plot of available rear-wheel horsepower versus speed you'll see that what it does is push the power curve in each gear down to lower speeds, but it doesn't raise the level. So the only gain comes at the low speed end - but on all of the bigger bikes acceleration at low speed is limited by traction (cruisers) or wheelies (everything else) - not by power.



Think about it this way, you're accelerating at the max, you've just shifted into second gear at say 90mph. You think, "If I'd just lowered the overall gearing I'd be accelerating faster." - but in that case why didn't you just stay in first gear longer. After all it IS a lower gear. The answer is that the power was fading in first gear; you were above the peak. And if you'd lowered the gearing you would have reached that fade at an even lower speed.



There is a very minor gain in lowering the overall gearing because the width (in terms of speed) of the power dips between gears is narrowed - but it's probably not measurable in the real world.



If you increase the number of gears, you can realize a gain by filling in and keeping the power closer to the maximum across the range. But that's a major transimission change. The gain of more gears is also partially offset by the time it takes to shift - which is why racers like power shifters.

 

I used to do a lot of freeway droning on my KZ750. I put a one tooth larger countershaft sprocket on it. This lowered my cruising revs by about 500 rpm. It had no effect on fuel mileage and reduced acceration in all gears. I eventually went back to stock gearing. So be cautious because changing gearing may not gain you any benefit.

 

Excellent explanation.. Since most folks don't like math I thought my bicycle analogy would help. I like your explanation better. Clear and concise. Good work.

 

Re: It's the ratio is the key..get on a bicycle

Playing cards in the spokes I remember showing my daughter how to do that and soon the whole neighborhood was doing it. i.e. kpaul passed it on to next generation of posers..

 

I think the guy in the shop is pulling *your* chain

 

Two things on this:



1 - lowering the gear can increase acceleration from a stop, as when you start moving you are at a higher rpm (into the real power) sooner. Plus you can slip the clutch less as engaging fully won't drop the revs. As someone else noted, this can be limited by having to back off anyway if the bike is wheely prone.



2 - I did this mod on a previous bike of mine for driveability. More specifically, the difference between first and second gear was substantial, and thus downshifting into a turn I found the drop to 1st to be too much, but felt the bike was lacking on acceleration out of the corner in 2nd. Changing the sprocket meant that I could be more in the power band in second and didn't have to drop into first. The pro racers do this all the time to get optimal gearing on a particular track. If you find yourself on certain roads, with certain speed corners, this could help.