Rear sprocket size?

[only3cylinders]

I've got a "98 sprint sport and although I spend most of my time between 35 and 50 mph in town I do use my bike for weekend trips. On these trips I spend a lot of time between 85 mph and 120 mph, often riding with a friend on a much bigger bike (honda 1100cc V65 magna) and I want to make sure I get the right size sprocket and chain when I replace them. My chain is shot and needing re-tightened every couple hundred miles. What should I buy that will keep me comfortable at higher speeds without losing any torque from a stop. Although I can't keep up with my buddy when he's clicking gears I am comfortable with the acceleration I have, but I wouldn't mind a little higher top end if I can get it without sacrificing power at lower speeds. Any recommendations on chain types and sprocket sizes? How do I find out what I have now?
Thanks

[faffi]

Provided your gearing is stock, you have a 17T front and 46T rear. Counting the rear is simple, the front less so because you need to remove the sprocket cover. This demands a new gasket and seal before refitting. So unless you are ready to park your bike while waiting for a new chain kit, you will have to chance the front sprocket size.

Note that if you gear your bike taller, it will NOT get faster. The ONLY time you will make a bike faster with taller gearing is if you already hit the rev limiter in the tallest gear.

So going to a taller gearing, your biggest advantage is more relaxed cruising at the expense of some acceleration.

I am currently running 17/43. That makes 5th pretty equal to what 6th is for you, with 6th dropping rpm 6.5% for a little more relaxed cruising. Calculated top speed is about 145mph with my gearing, something it doesn't have the power to reach. Stock gearing is good for about 135 mph at the rev limiter, still taller than the bike is able to reach most of the time.

As a compromise, the stock gearing is still quite good, striking the middle road between relaxed cruising and maximim performance.

If you want optimum performance for your type of riding, fit a 50T rear sprocket together with a 17T front.

[bradtx]

only3cylinders, Depending on your VIN there are two rear sprocket sizes, 43T and 46T, and one countershaft sprocket size, 17T. If you have a 43T rear sprocket a 46T will give better acceleration.

Brad

[KiwiGeoff]

You can go one tooth smaller on the rear - 42 is standard for the Daytona 1200 and easily available. This only makes a difference of about 120 rpm in top gear - but it is easier than messing with the front. That said it is probably best to replace both with the chain at the same time. Any taller gearing and you will compromise first gear by making it too tall for getting rolling and trickling through traffic etc. Most of the guys here go the other way in search of better acceleration.

Good luck - Kiwigeoff

[Roden]

17/45 = smiles all round! Good acceleration and cruising ability isn't compromised.

It will pull like a train in top gear from 60mph up, 4th or 5th gear at that speed and things become a bit more frantic!

Cheers,

Roden