05 WR450 decel pop

I just got a 05 WR450 with a possible jetting problem. I've searched alot of threads on this but can't seem to find the answer.

The bike rus good,but pops on decel and at times has a slight bog.The head pipe gets red pretty fast at idle.

I'm abit confused at what the various jets do. The previous owner said it has a 170 main, but was'nt sure about the pilot. The pilot is for idle circuit, I think, so could the be my popping problem,or do I need to rejet completely? It starts ,runs and idles good.

It has a FMF Q pipe,YZ stop, gray wire cut, and adjustable fuel screw.In california 1000 ft.

Sorry about the long winded post, but any advice would be welcome.

Can you get to the jets just by turning the carb or must you remove it?


best bet is a jetting kit, your 05 is extremely lean to meet emmisions req for cal. thumpertalk makes a kit to take off the smog. Its called the AIS kit in thumpertalk store. Try a larger pilot, you prob have a 45, go to 48 and try that with the AIS kit. Then do the free mods and a jd or factory pro jetting kit and unleash the beast you can get to the jets by rotating the carb but remember you have to take off the hot start on the top of the carb to rotate the carb.

I know it's a pain in the ass to wade thru all the jetting post's, but knowledge is power. Just like you want to waken your beast,power.

If your'e at all mechanically inclined, jet work is a breeze. Just alot of trial and error. I know you said "the previous owner said", do yourself a favor and find out for sure what you have in that FCR. Write it down, that way if you start to experiment-you'll always KNOW what you had. Pilot, main and the ap are gonna be the outlaws. Buy an adj. fuel screw-zip ty or whites or whatever, there's a ton of them out there now. The only way to get it spot on is go till you get rich, then back down slightly. All the time,try to make the throttle snappier. You'll know it once it's right on, grab a handful and wipe that grin off your face-mister. :thumbsup:

Once you know what's in there, and you do your homework-you'll not have to spend a ton on jets and such. Sounds like your lean to me, but hey. The ap jet should take care of your bog. And the main /pilot combo should cure your pop.

Make sure you check the TT store, for your screw and jet's.

When you search, use key's like -main-pilot-ap-ac pump-fuel screw-rich/lean.

You'll begin to see somewhat of a pattern, although every bike likes it just a little different. Good luck, your'e in the right place.

Jetting Database, first sticky in the forum...SC

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