increase or decrease

[gs550_caferacer_84]

ok so right now i have the stock rear sprocket on my 84 gs550, and am finding that i have lots of low end but not very much high end. does anyone have any recanmendations on what size or rear sprocket i should use so that i can increase my top end.??

 

[Steve]

A couple of questions come to mind:
1. If you are running flat-our in top gear, what is your speed?
2. If you downshift and run flat-out, what is your speed?

If you run faster in 5th gear than in 6th, you will need to add a tooth or two to the rear sprocket.

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[koolaid_kid]

Be careful when playing with your ratios. Front sprockets are cheap, but rear sprockets are expensive. And you need to watch your chain length as well. In other words, be very sure before making the change that it is what you want.

 

[tkent02]

You mean increase top end speed or increase top end acceleration?
Either way a larger rear or smaller front sprocket is what you need.
I played with this with my 550 a long time ago. Smaller rear sprocket for better cruising didn't work. Had to use lower gears more, it wouldn't pull 6th very well at all, fifth had a higher top speed than 6th. Tooo far between gears, you would wind out one and then shift and not be into th power in the next gear. What a dog. Gas mileage was worse. Stock gearing is as far as I would go in that direction. This little engine needs to spin.
Larger rear sprocket made the bike come alive, much better. The engine revs more, but that's what it needs to do.

 

[Agemax]

higher top end needs 1 tooth more on the front or 2 or 3 teeth less on the rear.
dont change any thing beyond that or the bike will bog down and have no acceleration or mid range pulling capability without banging up and down the box like a 2 stroke.

 

[Steve]

higher top end needs 1 tooth more on the front or 2 or 3 teeth less on the rear.
dont change any thing beyond that or the bike will bog down and have no acceleration or mid range pulling capability without banging up and down the box like a 2 stroke.

Changing one tooth on the front has about the same effect as changing three teeth on the rear, but, as tkent says, this little engine just doesn't have enough "oomph" to pull a taller ratio.

Prove it for yourself with my quick test mentioned above, compare speeds in 5th and 6th gears. You will likely need to add to the rear.

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