As a few have said, the stock 03 WR is a dog. Well its not a dog, its a pig! even worse than the stock 01 and 02 because of the jetting and restricted air box. But it can be great with the right mods. Right Bri? I have already explained the Cam timing issue. The jetting is so far off this year I can't believe it. It can be jetted with NO bog and NO hesitation at all. I won't go into that unless someone is really interested. Block the air cut valve. As someone else said, yes it does have the time retarding grey wire and it is in the 6 wire connection. The next BIG issue is the air box on the WR. It flows almost no air. If you don't believe it, do all the mods except the air box. Then, take the side cover off and test ride it. You won't believe it, provided you have done everything else right.

Larry,

We mentioned this mod in another thread - i.e. relocating the battery to behind the front number plate or mount it on the rear fender (via a fender bag) then open up the air box like the older models?

Larry,
I have seen your post and am intrested in how you made your wr RUN... Please E-Mail me as I am at work and it is "hard" to get on TT-Talk.
You mentioned jetting??? I recently bought a wr 250 2003. I have not done anything to it. It runs great in the low end but...nothing on top end. It has low end response, but it is hard to "wheelie".
Thank You..

larry,
would you be so kind to provide your jetting info along with the air info. sort of a starting point for those tuning in. (serious pun intended)

In addition to all the free mods posted and working to jet the bike well I will be adding an FMF SX powerbomb and Ti4 canister. Do you think that will greatly help the slugish performance on the WR? Also, if I still feel the bike feels sluggish what about taking out the battery (which unless i'm wrong will greatly reduce weight) and opening up the airbox through the battery hold. Will the WR kick over easily like the YZ? Any other suggestions? And Larry, if you could, PM me with your jetting tricks i would appreciate it. Thanks.

I did the gray wire, throttle stop, exhaust baffle, and airbox and this thing went from a complete dog to a fantastic machine. I ride with a friend that has a screamin '01 WR and mine is just as fast now. Every free mod helps tremendously. Disconnecting the grey wire did away with almost all of my off idle bog.
I wheelie with ease now without clutching in 1st 2nd and 3rd.
Let us know more about your jetting when you can.
Thanks

Larry,
You're jetting would be appreciated, please.

Larry,
Please post some jetting starting points. My 03 wr250 has such a bad bog or hesitation that it almost stalls, at anything less than full throttle. It runs ok at full throttle. My first guess was that the needle clip position was lean, but with a 185 stock main jet it sounds extremely rich compared to the 178 mj most people are running.The stock needle is obdvs #4 pos. The yz and non-usa models use a obelp #4 pos. Anyone know the difference? Please send help before I lose my mind. Anyone???

For the jetting to work properly, you should make all other mods. discussed. I run race fuel for purity. I'm alittle hesitant about giving jetting advice because it depends so much on temp. and elevation and your modifications. I race desert at sea level and ride Colorado at 12,000 but I'll talk about sea level to 3000 feet only. Plug the air cut valve so both air circuits are open and then you do not have to change the pilot AIR jet on the WR. See old posts of confusion. Scrap the 90 leak jet and go to a 70 or 60 if you can't get a 70. If you play with the leak jet there is no reason to do the BK mod as with the 426. Right Bri. Use a OBELQ needle. Clip at 2nd or 3rd position. Use a 42 0r 45 pilot depending on temp. and elevation now that you have plugged the AC valve. Main jet should be 168 to 172.
I won't go into all the technical issues of ACV, needle straight section or taper or why Yamaha did what they did for the USA 03 WR, but they are way off for our purpose here with all the mods. Don't forget on the 03 WR to open the air box. I'm not moving the battery, but more on that later. I,m getting too into this Thumper Talk thing.

Thanks for your time Larry.
Much appreciated.

larry,
have you looked at the OBELR needle?

Yes, I have OBELP, Q, R and S. I usually run OBELR if its warm in Colorado at 8,000 to 12,000 ft. If you do that, you can't go too lean on the pilot jet, usually 40 not less, because the R is very lean on the straight section of the needle. If you have everything set up correctly, there is absolutely NO bog at all on these 250f's.

Post deleted by MtBiker14

Don't smart off Mtbiker. I know where you live. Actually your 426 would still be missing if I had not fixed it.

Larry,
Thanks for the jetting info. That should give me some starting points. Are you still using the wr cam and timing with those settings? And do you have the baffle removed on the stock exhaust, or are you running an aftermarket?

Larry_K
Thanks for the post on jetting and mods.... WOW! were you right on. I can't believe the improvement. Way more power both low and high, no hesitation or stuttering.. I can open the throt at any RPM and it just pulls like crazy. It is a completly different bike. NOW, I can see why people like the YZF so much. Thanks loads.

Walt

Thanks for the comments. To answer your questions, I run a Yoshimura all ti exhaust and YZ timing ( 03 yz cam). I raced a 70 miles desert race on the 03 this weekend and it ran absolutely perfect with all the mods.

Yeehaa
Did the gray wire and 03yz cam, what a difference!! I was hitting the rev limiter with ease on the hill climbs. Now I can re-gear it to take advantage of the new power. Very happy again. Was beginning to regret selling my 01 until now. And it has the button....

Oh yea thanks for the jetting info LK

Larry
What Needle would you recommend for florida 70-95 deg
50'-100' above sea level

I've made the free mod (thank you TT members!) and have been quite impressed with the WR's improvement. Thanks to Yamafreek I have an 03 YZ cam in the mail to me (they still had 3 left as of yesterday... ) and am hoping to see more improvement. I also want to replace the stock exhaust - any suggestions or first hand feedback on performance gains?


Cumming, GA
03 WR250F - all the free mods, Pro Tapers and YZ cam on the way
94 XR650L - the old horse
02 DRZ 125
00 CBR 929