Yes smaller at front bigger at back =acceleration!
Yes bigger at front smaller at rear =top speed!
As mentioned if you go to high on gearing then you will lose top end due to the engine not able to pull top gear.
You need to ride your bike in top gear and see if the engine revs out.
If it does then go up on the front or down on back.
If your engine revs don't change much in top gear then you need to go down on the front up at rear.
Changing the front one tooth is the same as changing the back three.
Therefore the rear enables finer tuning of the ratios.
Always try the front first so you can get an easier tune,plus its cheaper and less work.
Ive changed my lads 125 cc pit gearing from 17t-37t to 15t-37t cuz the engine couldn't pull high revs in top gear. With the 17 it did 38mph but with the 15t it does 43mph .
Just play with different front sprokets until you get an average speed then try playing with rears to fine tune.
Example, my yx160 pulls 65+mph on 17t-41t on the road but off road(mx track) I don't get to use top gear.
I went right down to a 14t so I could use all gears,top speed 46mph.
If you want long gears then go high, short n revvy then go low.
For the road it is around the top gear ratio,so just play with the front until you get you fastest top speed. You will need to take into consideration that on some days you may have a strong head wind,if so the engine wouldn't pull higher revs, thus you will by going up n down in third n forth which is a pain in the neck.
So when you do find your top speed you have only two teeth to go up on at the rear to tune that difference.
I hope this helps and remember to try the front first or you will spend to much on rear sprokets.
One last point, if your sprokets or chain are knackered then all will need changing. If so, again get the front sprocket first to sort the gearing then get the others soon after.
Give Adam at PBS I ring on 01789766777 for parts.
Cheers n good luck
Hybrid Mode
