Sprocket Suggestions

[Guest]

There's lots of HIgh Speed roads here in Texas. I'm looking to get my 78 GS1000 some final drive gearing a little more suited for that. I don't want to loose all my low end grunt but would like to run 80 without the bike screaming at me. Any suggestions? I still have the 630 chain and sprockets on the bike now but am willing to go 530 if needed.

[Steve]

Your bike at 80 will probably be turning about the same revs that my bike does at 70.

It's not "screaming", it's "singing for joy".

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[TeamDar]

Just go up a tooth to 16 on the front. Dar

[rapidray]

What Dar said, exactly. You will be happy.
Ray.

[850 Combat]

How much does that drop the RPMs? My 1000Gs run about 5300k at 80, The motor isn't strained, but it is getting into the "Drone Zone" over 75 mph. Of course I don't think I have any leeway to adjust that.

[Steve]

Just go up a tooth to 16 on the front. Dar

How much does that drop the RPMs?

The stock sprockets on the '78 1000 were 15 and 42. Adding a tooth to the front will reduce RPM from 4000 to 3750.

My 1000Gs run about 5300k at 80, The motor isn't strained, but it is getting into the "Drone Zone" over 75 mph. Of course I don't think I have any leeway to adjust that.

Actually, you do.

Your final drive has a ratio of 3.1. If you can find a final drive from an '83/'84 1100, it has a ratio of 2.9. That would lower your 5300 RPM to about 4960 RPM. Does not matter if the 1100 is a G, GL or GK, as long as it's an 1100. The 850s of the same years still had the 3.1 final ratio.

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