Topic: 75-78 750F Chain

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I have a 76  750F SS with 77 forks and swingarm with Comstars.
I have been using a 630 chain, steel front sprocket and aluminum rear.
It's time to change driveline.
Any advantages to going back to a 530 setup?
The 630 front sprocket is 15 teeth rear is 47 . I want alittle more top end with less revs .
Suggestioms.
Thanks Keith

[Bodi]

The advantages: more chain choices, 630 is a rare chain now. You can use an O-ring/X-ring chain without hitting anything.
Disadvantages: hmmm....

For a lower final drive ratio, going up a tooth or two on the engine sprocket makes a bigger change than down one or two on the wheel sprocket, and the larger front sprocket should reduce chain load and increase chain life.

There's a good formula for road speed at RPM for assorted ratios at http://home.pacbell.net/pantaz/motorcycles/calc.html and you can download a spreadsheet to display speed vs RPM is all gears if you just enter the primary and gear ratios for your bike, these are in the service manual.

[TwoTired]

The 530 chain is lighter than the 630.

You won't get an extra 10MPH top speed with a gear change if that ratio moves the engine down or out of the power band.

Be prepared to downshift more gears for passing and other situations where acceleration is needed.

Be aware, the 630 chain has a different pitch than the 530, so sprocket tooth counts for the same ratio will be different.

Some chain info.
http://www.gizmology.net/sprockets.htm

Cheers,

[Bodi]

"Be aware, the 630 chain has a different pitch than the 530, so sprocket tooth counts for the same ratio will be different."

No, teeth is teeth. A 15/47 sprocket set will have the same ratio (3.133:1) regardless of the chain pitch.

[TwoTired]

"Be aware, the 630 chain has a different pitch than the 530, so sprocket tooth counts for the same ratio will be different."

No, teeth is teeth. A 15/47 sprocket set will have the same ratio (3.133:1) regardless of the chain pitch.

True, I don't word that right.  A 15 tooth sprocket for a 630 will be larger diameter than a 15 tooth sprocket for a 530.  Smaller front sprockets are harder on a chain and they wear faster.  To keep the same ratio and diameter of the front sprocket, more teeth front and rear will be required for the 530.

Cheers,