performance upgrades

I'm using the FMF Power Core 4 Sqd. It's soft on the bottom but pulls all the way to the rev limiter. Another upgrade you may want to consider is a piston from XR's Only which bumps compression to 11:1. I think it's cost is comparable to an after market muffler.

A year ago I sold my XR600 and bought a XR650R and have done all the honda upgrades, exhaust baffle, intake boot,jetting and unplugging the airbox. I am happy with the power but always looking for more. I have been hesitant about aftermarket pipe manufacturers claims and even magazine article tests, as they all seem to compare aftermarket stuff against the stock plugged up version. I would like to see some comps to the honda upgrade version, any thoghts? My 600 had a Thumper Racing 660 kit, a ceramic coated header but I ran the stock tailpiece with the baffle removed. I found this to be a great combination. I had tried an EAR Supertrapp and no matter what disc combination I ran, it never ran as well as with the stock tail piece. This combo provided some stump pulling torque and mid range which is best suited to most of the riding I do. I very much like the 650R as is, but would be interested in anyones results.

Honda will be offering a cam and piston combo in the very near future. Its the stuff that was developed on the Baja bikes. It has been written up in the mags (articles on riding the Baja winning bikes). They are claiming about 10 more horsepower with the cam, piston, and a pipe.

My 650l is in the same boat. I have a wb head pipe right now and am terribly happy with the low/mid increase and response. You will have to bump up your jetting and mess with the idle mixture. I will be running an E series wb muffler by next week. I am curious to see what happens.

Low cost performance gain: If you want more top end change to a 15/45 sprocket set.

Free performance gain: Loose 20 pounds. :)


With the listed mods bellow, i messed around with my stock pipe unplugged and my FMF power core IV. There was an obvious difference between them, bottom through top end. I did keep the stock header for better bottom end. I am very pleased with my set up. It feels as if the bike is 100lbs lighter because of the power increase. ( i could only wish the beast was 100lbs lighter) the only other addition i need to make is a Quicksilver pumper carb.

or you could always turbo charge your 650r if you want the ultimate in power. take a look at the pic in the xr 650r turbo post. I dunno what the cost would be to do this though. I think it'd be very expensive as i don't know alot of people that have done this mod to their xr

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