Topic: 18 tooth front sprocket

[uksparky]

Has anyone fitted a 18 tooth front sprocket to there 550...also i noticed the front stock sprocket is not a tight fit when the locking washer is on, should there be a shim behind the sprocket ...stock 17/37

[Bodi]

RPM at a given speed and maximum acceleration (in every gear and at all RPMs) will drop by about 5%. I don't know if this sprocket fits but if they sell them for a 550 it probably does, the diameter change is small. It's not enough of a change to make shift points super strange but you may notice a difference.
Why?
The engine is made to love high RPMs. It can't pull redline in top gear as it is. Will a 5% lower RPM at highway speed make a big difference? I think I would miss the first gear punch more than I would enjoy the more relaxed cruising rpm. But I usually install smaller engine sprockets and larger wheel sprockets for better acceleration and avoid long freeway rides... too boring.

[DaveBarbier]

No shim, just the sprocket and locking ring. Mine has a little play too, not a big deal.

Going up a size on the front will lower your rpms at a given speed in the same gear. Better for highway riding. Just making sure you're going the right way , in the research I did recently on the subject most people go the opposite direction.

It's easy to swap the front, so give it a shot and see how you like it.

Don't take this the wrong way, but seeing you're relatively new to the forum, I just wanted to say that o-ring chains on the 550 don't work without modification. Nothing leads me to believe you're using one, but I just wanted to try and help if you are With new sprockets and chains many people try and go the o-ring route for less maintenance. Just giving you a heads up.

[uksparky]

Just thinking about lower rims on Highway, but your right this engine likes to rev so I will leave it for now...yes I know the O ring chain is not for this engine thanks...I had a 550 in 2013..sold it and now I got another lol