All I can say is WOW!!!!!!!!!!!!!! YZ Timing.......

Hey y'all, just wanted to follow up with an update on my previous thread entitled "I think I may NEED to YZ time....."

OMG, As of Friday night, I've got a completely new bike!! First off, thanks a bunch to Hick for his YZ jetting suggestions!! Without anywhere else to start, I followed his suggestions to a T. I am almost spot on jetting wise, anywhere from 6,000 feet here in Boulder, all the way up to 12,000 feet, which I rode yesterday up to the continental divide. The bike ran amazingly everywhere, much quicker reving, more punch, and doesn't seem like I am missing anything down low (some people noted a little less down low when going to YZ timing). All I can say is AWSOME!!!

Now with new YZ timing and jetting, I've got a full fleged wheelie monster in any gear, it's like night and day. For any WR owners, that may be looking for additional punch from their bikes, I highely recommend the YZ timing. It's easy, free, and can be switched back easily. However, if you like your power smooth, by all means leave well enough alone.

Thanks for everyones input, it all helped in one way or another.

Peace, until next time..........

Dodger :):D

[ August 26, 2002, 10:26 AM: Message edited by: Dodger ]

It's good to hear that you took the plunge dodger! See it wasn't as hard to do as you thought was it? :) It's amazing how "dumbed down" the WR comes from the factory.

If you haven't done so yet go forth and do the BK mod. IMHO it is just as easy to do as the timing mod with great throttle snap! :D

Dodger what jetting did you end up with??

Sorry, guess I could have offered out my settings :) ....... little self centered I guess :D !

EKQ - clip #3

158 Main Jet

38 Pilot Jet

2 3/4 out on Pilot Screw

Spanking clean Carburator

Everything else is stock at this point jetting wise (for whatever all those other jets are). I rode at the same place both Sat and Sun, and have not done a ride around Boulder yet, I will be doing that tonight to see if I'm ok for 6K. When I first installed my carb on Friday night, the new jetting was a bit to lean on the pilot circuit, it wouldn't idle, but pulled hard all the way through WFO. No stumbles or anything. So I kept going out on the Pilot Screw a quarter turn at a time. By the time I hit 2 1/2, she idled fine but still had a little bit of a hanging idle. The 38 PS may be just a bit too lean, if she doesn't run right tonight around town, I'm going to go to a 40 pilot screw to see if that helps. But hey, I road all the way from 8K to 12K and back yesterday, and she pulled almost as hard at 12K as she does at 8K. That in itself is pretty amazing.

So anyone with the need to tinker, this one was fun :D ..........

Peace y'all....

Dodger :D:D

Wow sounds like you had great results. I thought about going YZ timed, but I rode a 01 YZ and seat of the pants it felt the same, even the YZ owner felt the same way. But free power, might have to consider it again. Wheelies in any gear you bet!

dodger, you answered my post. if you could reply under it ("more mx friendly bike") i'd appreciate any advice on undertaking this mod.


Dodger, when it gets colder I can easily see how you would need the 40 pilot in and around Boulder. The larger pilot would also probably work better with you stock PAJ.

Too bad you didn't do the jetting and timing individually, then you could report your experience as to which mod did what.


If you don't have a YZ needle your carb settings aren't anywhere near Dodgers. Changing to the YZ needle is the most comprehensive single change you can make, meaning it is a huge difference for just changing one part, a much larger thing than just changing a main or pilot jet size, for example. The only reason IMO your bike runs at all in the summer at higher elevations with such a large pilot (42) is because the stock "D" taper needle is very lean off the bottom and compensates for what would ordinarily be an overly rich pilot.

I am declaring jihad on that weird stock WR jetting. :)

Hey do you feel the WR lost anything in the tight trails or really knarly big hoonkin boulder mountain goat climbing???

I have been toying with putting the YZ cam jam on my 99 WR but it is just running so strong and is so nimble in the woods I dont want to mess with the whole jetting thing now that Im happy with it you know,,,,.

I am affraid I will lose the great traction the WR has on big, wet rocks, snow, mud, and the predictable power sliding I have on fast dirt roads and sand.

I actually have the YZ needle in it. I have a pretty good feel for bikes too, my other bike is actually my race bike, so I have some comparison. The 400 feels stronger in places than my 2002 YZ250. I know another guy from Colorado Springs that is running way richer on all the jets, YZ needle, but WR timed and has no problem with jetting, bike feels strong. After getting my 400 and talking with guys it seems to be a wide varity of jetting all with good results, you almost have to go bike by bike from what I'm hearing.

WR_Jason, I live in salida, CO and I ride nasty trails every day I YZ timed my bike and I wouldent go back. My bike runs great around town, at the local track, and better still on the hundreds of miles of single track in the area. I am ridding between 7500 and 14000' normally and I feel like the bike snaps to better when I need a little extera boost with the YZ timming. :)

Way cool, thanks. I'm running 158 main, 42 pilot, and about 2 1/2 out on the air screw. YZ timed and ran it up to 12500 a few weeks ago and it went well. Sounds like we are close to each others settings.

yea i went to YZ timing and all that happened to me is i go through tires more now. Bike just goes and goes. I give it gas and it just spinns. Amazing. I cant inagine what a 426 or the 450 will do. Any way i am due for a cheap tire again. Good luck with the timing.


Originally posted by endurodog:

I actually have the YZ needle in it.

I just noticed you have a 400, so I'll take back what I said about the 42 pilot, that may be okay for you, a smaller motor will likely want a larger jet...

...and I have no experience jetting the 400 anyway.


No problem I appreciate the input, thats why I come here.

Huh, thanks for the input, :) well its basicly a free mod except for the needle, and new jets, I just hate to mess with it since its so dialed in now and starts first or second kick when cold,,,

Well, I suppose a valve clearance check is in order soon,,,, sooo, Ill clock the cam and see how it goes. Is there ANY chance of it running ok if I retime it on the jettng I have??? I have not messed with my jetting since I got it diled where I like it about 8 months ago but I belive I have a 170 main jet, and I had to bump the PJ up to a 38 I think or maybe even a 40, I have it wirtten down in my book,,,, I run it between 200 feet and 300 feet with most of my riding between 1500 and 2500 ft.

It would just be cool If I could get a feel for it with out rejetting,,,, but I suppose thats a slim chance,,,.

Yo Jason, from what I've been told and experienced, you don't need to rejet for new timing, however it seems to be quite a compliment to the timing. I was lucky enough for things to work out timing wise for me (that being actual clock time), I rejetted on Thusday night, and was able to try out the new jetting Friday night just before doing the YZ timing. There was no difference between before and after the YZ timing as far as the jetting goes.

If you got a little time, don't be afraid to experiment a little with your jetting. You've got a bench mark already, and sometimes you just don't know what your missing. I know I was, before the jetting, I considered my bike to be running as well as it could. But man oh man, what at difference just YZ jetting did, let alone the timing.


Dodger :):D


I too have an 01 and have toyed with the idea of going to YZ timing to get a little more punch. I realize I'd have to rejet and am a little reluctant to fiddle with it because it's somewhat dialed right now. your opinion, can I use the same numbers as Dodger and expect results or should they be different due to my relative elevation (about 2500 to 6000).


Hey Dodger, well done on the YZ Timing! I agree 100 percent, it’s terrific and would not change back. I love running tight twisting trails in third gear. The only need to downshift is the sand filed trails, but second gear is perfect for that. Hill climbing is a snap! Third gear no problem!


Changing the cam timing does nothing to affect jetting in my experience. It may change the idle characteristics a bit…

What do you mean when you say your jetting is dialed? My own personal experience with the WR makes me biased, but I’ll say if you still have the stock needle you are not dialed.

The WR comes with, uhmm, strange jetting because of the strangled exhaust and sealed airbox. Once you rid your poor bike of those ridiculous add-ons it is essentially a YZ motor, and IMO then should be jetted as such (100k YZ owners can’t all be wrong…)

Lessee Mojo, at your elevation, and being in WA which is probably as cold or colder than CO I’d say bone-stock YZ jetting or a tad leaner will be a good starting point for you to work from. This would only involve two parts, the stock YZ needle (’01 or newer) and the stock YZ Pilot Air Jet.

What jetting changes from stock have you already made?


I did type "somewhat" dialed. I agree this engine has a good deal of untapped power with the stock jetting.

I have a Canadian model. If I can remember correctly, the pilot air jet (?) is different than US and the needle is also a bit different.

Ive only changed the main jet to a 168 from 170 stock and raised the clip position two (thereby dropping the needle to lean it up). I had purchased a US pipe, and ran with the plug in (I like to talk with my 7 year old son when we ride together). I went back to the Canadian pipe, which is much more free flowing than US with plug in. BK mod done also, but without much notable change.

I've always run rich it seems, and was fouling plugs on a regular basis until I dropped the needle. Sounds like if I use Dodger's settings, It should be a starting point.

Is it a major issue leaving the pipe the way it is?

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now