1981 Suzuki gs550t gearing????

[Guest]

Has anyone changed the sprockets from 15-50tooth to a different ratio such as 17t-42t for better highway mileage as I travel mostly highway about 90% of the time.

[Nessism]

Gearing the bike for lower rpm's won't automatically result in better mileage. And the change you propose is extreme; a lot of clutch slipping will be needed to launch the bike and acceleration will be much slower.

I suggest moving to a 16T front sprocket, assuming there is enough clearance. That will drop the freeway rpm noticeably without making the bike a total dog off the line and when driving around town.

[Steve]

Agree. Start with the 16-tooth front sprocket. If that isn't quite enough, maybe try a 48-tooth rear sprocket to match.
The stock ratio is 3.33:1. The 16-tooth front will take it to 3.125:1. Adding the 48-tooth rear will be a 3.00:1.

If you go much further than that, you will be taking the engine out of its efficient range, so you will have to have the throttle open farther, offsetting any potential improvements due to lower engine speed.

Let it spin where it's efficient, just get used to the sound.

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