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2002 WR250F standard mods question

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My buddy picked up a very low hour 02 WR250F and I did some work on it for him. Swapped a decompression exhaust cam in from a YZF, checked valve clearance, gray wire mod and had to replace a radiator bent in a crash I guess. It already had a GYTR insert in the factory muffler, JD jet kit and throttle stop screw shortened.

Now it starts easily and runs absolutely beautiful but just doesn't have the grunt I think it should and want to make sure I'm not missing something. There was some difference with the cam / gray wire mod but really not a lot. I pulled the rear off the muffler to check the arrestor screen - looks fine. Running blue needle in 5th from top, 42 pilot and 185 main. Tried moving needle - no better. Double checked cam timing - it's good. Is there a quick way to verify I have a YZF cam and not a WRF cam without resorting to a degree wheel? Have there been any cases of the CDI's not running the more aggressive timing curve with the gray wire disconnected? Is the muffler hurting power? I don't really think it is and we both like it being fairly quiet though. Are there any other differences in the 02 engines I don't know about? Let me rephrase that - are there any mechanical differences between his 02 engine and 03 - say 05 that affect power? Specs I have seen list compression ratio as the same. I know crank got some reliability upgrades in 03 but the shouldn't affect power. I don't really have a good comparison because mine 03 YZF was a basket case and already had a 290 kit. He previously had a 04 CRF250 that did have a lot more bottom / mid than this WRF. I gave it back to him for now so he can have some fun but I want to get it back and do some more digging. Thanks for any info. Clay

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Did it have power before the mods?

Compression check?

 

My bike lost a bit of power with my JD kit installed, but I have not done my wot plug test yet, and it was running lean before the mods. (full Akrapovic exhaust with stock carb, it would pop and backfire )

I guess you are at a low elevation?

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Carburetor and exhaust mods were already done by previous owner. I installed the decompression cam (supposedly a YZF cam) and disconnected the gray wire. We both rode it before the cam / wire mods and it ran really good - just seemed like it was lacking bottom / midrange power. After cam / wire mods it did pick up a little but not really much. Still runs very good. No bogs, stumbles at all. Cranks easily. Pulls through rpm range really smooth and revs well - just overall seems down on torque. Everything I see says it is very low hour - original tires, very little paint worn off sidecovers, etc. so I'm not thinking it needs a piston. Our actual elevation is around 350 ft. but this time of year density altitudes regularly go below sea level. I've got another thing or two to check but wanted to see if anyone had seen this before or is this just what it is. Clay

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