Gearing down a 2003 XR650R

I picked up a 2003 XR650 about a month ago and I'm loving it. The only problem is that I do a lot of trail riding and the bike can't go slow enough through some of the more technical terrain. I find myself stalling the bike and/or popping the clutch far too often. I would like to gear my bike down a bit and wanted to know if anyone else has any recommendations or experience with this. Would it be sufficient to get a larger rear sprocket or am I going to have to get new gears?


I also ride in the tight stuff and was having the same problem. I dropped one tooth on the front sprocket. Stock chain still worked and it seemed to fix the problem. Does'nt seem to be wearing the chain guide or sprocket any faster than normal(like some say). Quiksilver carb helped alot as well, but that's a different story.

Good Luck! :)

Don't worry about getting new gears. A sprocket change is all you need, but how much of a change depends on your needs. The stock front sprocket is 14 teeth while the back one is 48 teeth for the US version of the XR650R. You can either install a larger rear sprocket or a smaller front sprocket to gear down. Before I installed my z-Start (awesome product for trail riding!), I changed my front sprocket to a 13T, which is about the same ratio as using a 52T rear. That was probably one of the best low cost changes I made for trail riding. I wouldn't use a front sprocket smaller than 13T, so if you need an even lower ratio, then go to a larger rear. Some guys really like the 13/51 combo, but the 13/48 worked nicely for me and I still had a 90 MPH top speed. Changing the front sprocket is also inexpensive, quick & easy to do :)

Yeah, qadsan is right on...changing the sprockets is all you need. I went the opposite way of qadsan however and went with the 52t rear sprocket. I love the set up for the trails and the bike still huals ass in the open.


What is the "z-start"?

What is the "z-start"?

The z-Start is an auto clutch like the products from Revloc & EFM, but much less epensive, easy to install, user configurable and very trick. The z-Start replaces the pressure plate on your existing clutch and allows your bike to idle in gear while it does the clutching and declutching for you based on how you've set it up. You can adjust the stall speed as well as how quickly it engages. It also provides more clamping pressure than the stock clutch. No matter how hard you jam on the rear brake when coming into a corner, the bike won't stall because the z-Start is seemlessly clutching and declutching for you. The same is true on hills. I recently climbed a big hill and hit a rock near the top of the hill that nearly bucked me off my bike. The bike practically came to a stop in 2nd gear without stalling (thanks to the z-Start) and I thought I was going down while holding on for dear life, but I gassed it and it pulled me up the remainder of the hill. Without the z-Start, I would have had to pull in the clutch and perfectly feather it while I was nearly being bucked off. I may have made it, but I doubt I would have been that lucky and the bike probably would have stalled and I hopefully would have bailed.

The z-Start is awesome on trails because you can easily ride a gear higher than usually would and still handle the technical stuff with ease. For instance, I could ride up a narrow twisty hill in 2nd and come to near stop at the top of the hill without ever down shifting, then once I decide my direction I'd simply gas it and be off without using the clutch or shifting down. The z-Start keeps you in the powerband longer by perfectly clutching & declutching for you automatically. It's almost like having an automatic gearbox for certain types of riding.

I can't quite put it into words well enough, but it makes riding a whole new positive experience and I can't recommend it enough.

When I first heard of products like this, I couldn't see any benefit, but then the concept grew on me over a few months and I kept reading more and more positive experiences from CRF450, YZF & KTM owners who raved about their auto clutches, espeically for riding technical stuff, so I bought one and think its just awesome. It even comes with a 30 day money back guarantee, but there's no way I'm sending mine back :) If you want to read more about auto clutches, try searching the CRF450, YZF & KTM forums here on ThumperTalk as that's where these products started. The z-Start for the XR650R is a new application and not even listed on their web site yet, but its the same price as the other models. Here's the link to Rekluse Motorsports who makes the z-Start if you want to check it out

Thanks for all your input, guys. It is greatly appreciated.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now