Gears... 15/41 Stock v.s. 18/38 mod

[Jvacustoms]

I was thinking about making the bike faster by changing gears... I did a bit of research and with a 18/38 setup it looks like the bike would run alot faster and still keep lower rpms. according to the numbers i saw can anyone confirm or deny this theory all information is welcome. I wanted to make it slightly faster without killing it and the numbers i calc'ed are nice but I dont wanna spend money on something that i will remove if i think it will kill my bike.

also thinking about a 130 main jet a k&n air filter piped straight to the carb with no air box front (cold air effect) and a dual stock pipe setup... also any information welcome.



Ride with respect.
Respect the Ride.

[Water Warrior 2]

That suggested gearing will not work. The best you can do is go up one tooth on the front sprocket. The bike doesn't have the power to use that gearing unless you are "always" going down hill with a tail wind.
You would be changing the overall gearing by at least 25% and the bike won't do it successfully.

[Jvacustoms]

how do u calculate the 25% I dont know how to calculate it

also don't you loose top end when doing this?

I was thinking about just a 15/38 to start... but that would change the overall length of the chain distance

[JWR]

Originally Posted by Jvacustoms

I was thinking about making the bike faster by changing gears... I did a bit of research and with a 18/38 setup it looks like the bike would run alot faster and still keep lower rpms. according to the numbers i saw can anyone confirm or deny this theory all information is welcome. I wanted to make it slightly faster without killing it and the numbers i calc'ed are nice but I dont wanna spend money on something that i will remove if i think it will kill my bike.

also thinking about a 130 main jet a k&n air filter piped straight to the carb with no air box front (cold air effect) and a dual stock pipe setup... also any information welcome.



Ride with respect.
Respect the Ride.

I don't think there is enough room for that large of a counter sprocket???
I had a 16 and it is quite a bit larger than a 15.
Would probably have to shorten chain.

Playing with the carbs is a sure way to change the speed of the GZ...
No one has really gotten gains from carb work.

May have a little issue with shifter and or chain guard being in the way...
Be the first to make it happen.

But hey it is only time and money, keep us posted on the progress.

Not trying to be a rain on your parade, but, the GZ is what it is.
YMMV.

[JWR]

Ever 1 tooth up in the front = 3 down in the rear.

Be the same as going to a 30 tooth rear.

[5th_bike]

Originally Posted by Jvacustoms

how do u calculate the 25% I dont know how to calculate it

Simple, (18/38)/(15/41) = 1.294.... (according to the calculator on my phone).

So, the proposed gear ratio increases by more than 29%.

Just try the 16 tooth up front, which is a change of 6.7% you'll see the bike will already have more trouble with slight slopes up in 5th gear. And not go any faster.

[Jvacustoms]

would that kill the bike ?

the 30 tooth rear?

[Water Warrior 2]

18 divided by 15 time 100 = 120%
38 divided by 41 = 92.7%
An increase of 20% up front and a decrease at the rear of 7.3% is a total of 27.3% change in the gearing.
Just try a 16 tooth sprocket up front, you might like it and if you don't it is a cheap experiment.

[Jvacustoms]

I am looking for top end really not fuel economy or quickness just nice torqued up top end pull the hills and such with a greater speed.

[Water Warrior 2]

Originally Posted by Jvacustoms

would that kill the bike ?

the 30 tooth rear?

Only if you ride it.