'05 WR450 Tuning - Uncorking, Jetting
Posted November 16, 2004 - 07:43 PM
My question is with regards to jetting: With the above changes, will adjusting the fuel mixture screw be enough to insure the engine doesn't run lean? I will check the plug but wanted to get a baseline to start. The dealer says I don't need to rejet but am not 100% convinced he is correct. Please help if you have gone thru this on a '05. Thanks.
Per Yamaha manual:
main jet 165, pilot jet 45
Posted November 16, 2004 - 09:29 PM
Posted November 16, 2004 - 10:14 PM
BTW you can just rotate the carb to get to the needle on the 04, very easy and forward install
Posted November 17, 2004 - 11:55 AM
Thanks for the info. The '05 stock needle (per manual) is not adjustable - only one groove. Will the stadard 5 groove JD needle work? If so, I'll get the JD kit, but if it doesn't ship right away, will the wr450 be too lean to run uncorked with stock jetting or will to just not be tuned ideally? I'm planning on a 2 day trip next week and may not have the time in rejet unless it arrives before this weekend. Also, can I just rotate the carb to access the needle or did you have to remove the carb? My xr400 was not so easy. Thanks
You can shim the needle with washers... I have the 04 WR needle in my 03, it works quite nicely and has 7 grooves. I had the carb out anyways, but I don't think you can rotate it enough to get to the needle.
Posted November 17, 2004 - 07:29 PM
Posted November 17, 2004 - 11:28 PM
Posted November 17, 2004 - 11:45 PM
no backfireing unless its ran out of fuel
[thank god for the reserve].but i havent
taken out the baffel as the back of my
exaust is welded on
Posted November 18, 2004 - 07:20 AM
Posted November 18, 2004 - 09:29 AM
Posted November 18, 2004 - 02:44 PM
Posted November 18, 2004 - 07:27 PM
Posted November 19, 2004 - 07:59 PM
Posted November 19, 2004 - 09:15 PM
Posted November 19, 2004 - 09:18 PM
Posted November 20, 2004 - 03:55 PM
I put the 170 main with the blue needle in the 4th position. Full baffle removed, airbox plug yanked, yz stop and gray wire pulled. The bike runs great and the plug was nice and tan but the "Scotts" mixture screw doesn't change idle much. There is a slight drop when the screw is closed but the bike still runs. Between 1/4 and 2 turns the idle remains the same. Idle is good and the bike runs great. Good low, mid and high acceleration and no backfire or stumble. Is my setup ok? Thanks, Bob
Posted November 20, 2004 - 09:51 PM
Posted November 20, 2004 - 10:49 PM
Looks like Yamaha took care of the air box mod on the '05. At least on top. Mine was already open and breathing from the factory. Course, this does make sense if you're objective is green sticker (factory speaking). Lean out the fuel - shove in the air......see how clean it is !!!
really? i think thats y me and my dad couldnt find the air box boot thing. we were trying to find it so we could take it out but we couldnt find it. did they not put it in the 05 models?
Posted November 21, 2004 - 08:01 AM