any outlandish 650r mods other than uncorking??

Just curious if anyone has done any major engine mods EX: Port and polishing, cam changes, timming changes, increased compression ratio's, increased bore and stroke etc. if so what are the results of the power increase? Any tricked out mods on those flat-trackers and supermotard bikes? what is the max Hp anyone has got out of one of these machines without mounting a turbo on it?

Nothing outlandish: stag 1 cam, 10.5:1 piston, K&N filter, Carrillo rod, 17 inch rims, Talon hubs, and dual sport kit.

But I have questions for you. How is your scoot's carburetion? Working fine? Have you eliminated the dreaded hanging idle? If so, what is your elevation? Do you know the approximate hole sizes in a 75 pilot jet? I am currently still trying to get it right.

The only really outlandish XR650R I've ever ridden was Rob Barnum's bike. He had the 680 kit installed with his own custom cam grind and he does all his own custom porting. Everything was blueprinted and balanced and of course he runs an Edelbrock Qwiksilver pumper carb. I'm not sure about his compression ratio, but I recall him saying his bike ran on pump gas, so it couldn't have been too high. His bike also used the Carrillo rod and all the internal bearings were specially sourced. The engine was cryo treated and many of the internal parts were coated with a special aerospace coating for added durability and to reduce friction. His bike was running 15/45 gearing at that time and it pulled significantly harder than my uncorked bike which was running 13/48 with a stage one cam, HRC exhaust, Edelbrock pumper carb, airbox mod, etc. Since the time I rode his bike about a year back, it's my understanding that his bike is significantly faster now than it ever was and he said he's still looking for more power to run taller gearing :).


not sure of the size hole in the 75 pilot. Going from the 72 to 75 pilot was the perfect increase and the 103mm piston breathed just fine at idle after that. not sure of my elevation. I am located in eastern ohio.

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