Do I need to change Jetting for my Y2K WR400 W/O Baffle elev.900ft or leave it stock?
Posted April 27, 2000 - 06:38 PM
Mike from Oregon
Posted April 27, 2000 - 07:50 PM
I ran my stock jetting (99 WR So. Cal 0-3000ft) all stock with just the airbox lid removed and it ran just fine. Mine is a Canadian model and the baffle doesn't come out.
I put a YZ pipe on and it still ran pretty good, but it popped a bit with the throttle off and seemed like it was running a little hot (lean). I didn't ride it much like that and didn't bother messing with the air(or is it fuel )screw to try and fix the popping.
I went to YZ timing and jetted it per the recommendations posted here and now she runs sweet.
I suspect you would be fine with the stock jets. I saw at one entry in the jetting section that was running stock pipe w/o baffle and stock jets in Arizona (low altitude, but dry).
As always WMMV and you should take some plug readings, etc, to be sure. If you haven't already tried, check out the Technical section and also do a search of the General Discussion, there has been a lot talk about jetting around here.
Posted April 28, 2000 - 07:02 AM
The 98-88 jetting does not work for us, but it is close. You ride in Oregon- a wet place, right? 900 feet isn't too high.
What are your symptoms? I had to goto a 45 pilot and 172 MJ, 4th clip stock needle with the snorkel removed and exhaust tip out(600-900 feet ohio, 65 degrees). Otherwise I had a high idle at no load, would hesitate and lug on the bottom end, popped when chopping the gas.
Make or buy a 3" small tip screwdriver to adjust the pilot (fuel) screw. Clockwise is leaner, counterclock is richer.
I bet you it will run better just by turning the pilot out. Turn it 1/16 turn at a time, a little is a lot. Then move up to a larger MJ-maybe 168-170. Do a spark plug test again.
The needle clip may also have to be adjusted or even a new needle entirely.
The actual work of changing jets is a piece of cake, don't worry about that. The process of checking the spark plug and riding it between changes to feel for differences takes a while. good luck
Posted April 28, 2000 - 08:41 AM
Posted April 28, 2000 - 01:58 PM
Mike from Oregon
Posted April 29, 2000 - 05:22 PM
Posted May 01, 2000 - 01:30 PM