a little disappointed and curious at the same time

hey all, ao i just got a 03 wr450 in july. figured i would ride it the way it was for a while before i would start do any mods to it. i am slowly finding out that there have been things already do to. this i am not complaining about just a little disappointed because i figured i was going to be able to do all the free mods to wake the bike up a little. first thing i noticed was the PMB insert. which it doesnt run lean so it must be jetted for the open exhaust. then today i went to go do the grey wire mod only to find out it had already been done. not sure about the ais removal. but non-the-less i rode my buddys yz250f and it seemed to have just as much nut as my bike did. so im curious, whats next as far as getting some more nut out of it.

The YZ250F is a much lighter and harder hitting bike (with a close ratio tranny) than the WR450. Kinda of an apples to oranges comparison.

One small thing may help: is the air filter clean?

If you liked the YZ, maybe a gearing change could help you a little?

It's all in the weight of the flywheel. The heavy flywheel keeps the motor from spooling up as fast. It is also why you can lug that thing without much clutch abuse and constant stalling. I like watching others abuse MX bikes through nasty ST stuff...while I hardly ever need to touch the clutch.

yes i just cleaned the air filter so i know thats not it. i was thinking about doing a gear change. i know im running a 14/49 gear setup. counted it the other day. i guess i just need to figure out what gearing works best for what i do. if anyone has a good setup up that they liked, im open to suggestions. i'll also search around a little bit. i ride mostly trails that are open with some tight ST thrown in there. definately a mix of trails and conditions. thanks guys. and i know what you mean about not stalling all the time. very nice!

yes i just cleaned the air filter so i know thats not it. i was thinking about doing a gear change. i know im running a 14/49 gear setup. counted it the other day. i guess i just need to figure out what gearing works best for what i do. if anyone has a good setup up that they liked, im open to suggestions. i'll also search around a little bit. i ride mostly trails that are open with some tight ST thrown in there. definately a mix of trails and conditions. thanks guys. and i know what you mean about not stalling all the time. very nice!

Put a YZ exhaust cam in it and a decent exhaust. Something other than stock with an insert. FMF q2 or q4 if you want to be legal or a factory 4.1 if not.

Go to a 14/51, or 14/52 sprocket combo...you will certainly notice the difference...and it's cheap to try.....

I run a 13/52 ratio and its pretty snappy. My 2003 450 has all the free mods plus a couple extras, full FMF, 2004 YZ head and valves. The bottom end is noticeably hotter than my similarly equipped 2010 KTM 450 XC-W. Even up against the tank it lifts my outfitted 220lb through the first 3 gears with no effort.

i was thinking about just doing a 13 tooth for now and seeing how it is.

get rid of that stock WR pipe

Even with the insert. It restricts the motor way too much. The WR engine ment to run.Detuned it runs like crap

At least by a used a used stock YZ exhaust

hey all, ao i just got a 03 wr450 in july. figured i would ride it the way it was for a while before i would start do any mods to it. i am slowly finding out that there have been things already do to. this i am not complaining about just a little disappointed because i figured i was going to be able to do all the free mods to wake the bike up a little. first thing i noticed was the PMB insert. which it doesnt run lean so it must be jetted for the open exhaust. then today i went to go do the grey wire mod only to find out it had already been done. not sure about the ais removal. but non-the-less i rode my buddys yz250f and it seemed to have just as much nut as my bike did. so im curious, whats next as far as getting some more nut out of it.

the wr is a gentle giant. It doesn't bark. But it is strong, very strong in fact. Its an 03, so its probably got some miles on it. Put some new rings and a piston in it and also check those valves. That's where the power is.

do not assume that the jetting is correct. Check it for yourself.

yah when i got it i took it to my mech. to have the valves checked and the intake valve was wicked tight. he told me that a motor job was due but i could ride it this summer and be fine. so thats on my list of things to do for sure.

yah when i got it i took it to my mech. to have the valves checked and the intake valve was wicked tight. he told me that a motor job was due but i could ride it this summer and be fine. so thats on my list of things to do for sure.

At least you know know. don't be afraid to do most of the motor work yourself. I did mine earlier this year and it was much easier than I thought.

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