changing sprockets for lower rpms?

[cmn1771]

1980 gs550e

i want lower rpms on hwy. right now iv got stock gearing (50tooth sprocket on rear. 15 tooth on front) should i go up to 16 tooth on front, or down to 47tooth on rear?

i dont want to get it geared too high that it doesnt pull. what do u guys suggest?

thanks
-matt

[mike_of_bbg]

Try a 16 up front, you can always switch it back out if you don't like it. I just went from 15/50 to 16/50 and didn't notice the drop in power as much as the drop in highway RPMs. Then again, I haven't put many miles on it.

[BassCliff]

Hi,

What do I know? I've got a shaft drive.

But both of those suggestions will end up doing the about same thing to your gear ratio. One up on the front is roughly equal to three down on the rear. Here's a calculator:

http://www.qddev.com/demos/sprockets/sprocketratios2.shtml

Thank you for your indulgence,

BassCliff

[mike_of_bbg]

But both of those suggestions will end up doing the about same thing to your gear ratio. One up on the front is roughly equal to three down on the rear.

Exactly. But the front sprocket is both cheaper and easier to replace. The other factor would be the chain length of course. If you drop in the rear your axle will move back, a bit further than it will move forward if you add one in the front.

[mike_of_bbg]

BTW, who makes a 47? I went JT sprockets and it seemed their next step down from 50 was 45. Stock gearing on the 81-82 550Ls was 15/49.

Oh, and you probably can't go much larger than a 16, maybe a 17, on the front on an 8V 550 because of the clutch pushrod.

[cmn1771]

BTW, who makes a 47? I went JT sprockets and it seemed their next step down from 50 was 45. Stock gearing on the 81-82 550Ls was 15/49.

Oh, and you probably can't go much larger than a 16, maybe a 17, on the front on an 8V 550 because of the clutch pushrod.

z1enterprises

[mike_of_bbg]

Ah, it's a different sprocket series on the rear between your 80 550E and my 82 550L. The JTR814 goes right from 45 to 50. Thought I was losing my mind for a second.

[cmn1771]

oh, where do u guys get the washer that u bend down onto the front sprocket nut to lock it in place?

is it diff size for diff models?

[mike_of_bbg]

I reused my old one. It's still available as an OEM part for about $3 - Z1 should be able to get it for you no problem.

[cmn1771]

well, i installed a 16t front sprocket. i was afraid it would decrease acceleration so much that it would kill the fun factor. but im pleasantly surprised with the results.

cant really tell any diff in accelerartion, but i do notice the buzz in the handlebars is gone! its turning about 4700 rpms at 60mph now. before it was about 5200. a much smoother ride now. maybe i can keep the front tire on the ground now , ha ha!

-matt

[JEEPRUSTY]

How much clearance do you have with a 16 tooth sprocket?
is it eniugh that a worn chain could hit it due to the centrifugal force on it?

[cmn1771]

theres enough clearance.

[mike_of_bbg]

Yeah one probably does not want to put anything larger than a 16T on an 8V 550.

I recall you asking me before, and noted yesterday that I was turning about 5200 @ 65mph with my 16/50. I'm with you, I don't notice much power loss at all.