XR650R range & bigger tank

I have an XR 650R, stock tank, uncorked, rejetted, that rips, but runs out into reserve at 42 miles or so. I'm talking about trail riding, or GP/cross country stuff. Is this about normal? What is the opinion on the bigger tanks (Clark or IMS?) Are they bulky? Top heavy when full? worth adding?

I'd like a little more range for some 50 mile rides we are planning this summer.


As you know there are many variables to consider for mileage. Gearing, jetting, throttle, load, terrain, etc. Your mileage would improve considerably on the highway or open desert areas with 15/45 gearing for example.

You get 42 miles before hitting reserve. That's using 2 gallons so your are getting 21 mpg. That is not unreasonable for trail riding with a big bore engine.

I would buy the Clark 4.3 gal tank for the XR650R. I have read alot of rider reviews and this one is highly recommended.


I run an IMS 4.6 gallon tank to pre-run with and Ims 3.4 to race with. The 4.6 is about as slim as the stock except when your really on the tank. the 3.4 is as slim as stock.


Same thing happened to my buddy at the Silver Dollar PR at Brown's Camp. 42 miles in it died and he had to go to reserve, I couldn't believe it. My 600 doesn't hit reserve until 75 or so riding the same trails with a stock tank. The 650 is sweet, but there are times I am happy to have the old school technology. Only if my suspension could keep up :)

xrforme, I have an IMS tank for sale. Not sure if it's the 4.3 or 4.6 gallon. Let me know if you're interested.

Three things - first is that there is a lot of fuel on the other side of the tank, clear tanks show how much fuel gets trapped over there. I've had to lay the bike down to get the fuel over on the petcock side. Second is that stock carb doesn't help, since installing a flat slide Mikuni my BRP is averaging 35 MPG. Third is you my be running too rich, try going down on the main jet,(168 maybe).

I just picked up a Clark 4.3 gal tank at lunch for $183. I did a 50 mile loop last week end with out hitting reserve but the gas line is right there at the top of the fill tube. I only have 150 miles on the bike so I don't really know how far or what kind of milage I can get. Just to be safe I got the big tank.

I had a similar expierence, then I rejetted, and began getting 35mpg. I have a Big Gun exhaust and stock carb, aounds like you need to rejet to larger main and probably pilot also. I have a IMS 3.4gal and never use it now that I have the jetting right. :)

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