Weird Jetting problem
Posted April 22, 2007 - 11:17 PM
i had the standard needle and main jet was 160 and 48 pilot and it didnt run too bad.
I bought a JD jetting kit and installed the 168 main jet and red needle on clip 5.
It ran alot smoother at midrange - it used to have a bit of a rough misfire or something. BUT when the revs get to top end it would burble and struggle like it was way too rich.
So i changed the main jet to 165 and it got better but it still struggled a bit.
Now im back to 160 and its almost back to normal i think.
the tempreture is only about 15 degrees celcius and im about 250 metres above sea level.
The bike felt like it had more power with the larger jets and everyone else runs a 168 with no problems.
what could be causing the bike to be soo rich up at top revs.
any suggestions to what i should do?
I also installed the rubber o-ring on the fuel pump acctuator and now it has more punch from that mod.
i dont want to stuff around forever with my jetting so i thought i ask for some opinions.
by the way my air filter is clean and not overoiled and my airbox is opened up.
Thanks for the help in advance.
Posted April 23, 2007 - 10:40 PM
When i had the 168 in, it pulled alot harder to top end but then just started spluttering at about 3/4 top revs.
by indys chart i should be running a 170 main.
i want to get it running right because with the 160 jet it dosent pull hard enough up top, and i dont think i have ever hit the rev limiter on the bike - i think it just splutters up top when i originally thought that was the rev limiter.
Please help Anyone.
Posted April 24, 2007 - 04:19 AM
I am no jetting guru, maybe you should PM one of them like Indy or Grayracer. Sorry I can't be much help.
Posted April 24, 2007 - 04:51 AM
Anyway, i have removed the snorkel and cut out the two holes on the side of the air box.
Throttle stop has been replaced with YZ.
exhaust has been replaced with wileyco muffler.
grey wire cut.
i think thats all of the free mods.
I seem to be the only one with this problem, there is nothing similar to my problem when i search for it, except for earlier WR's with a removable main air jet, but the 450's has a fixed 200 MAJ.
just keep throwing your theorys my way, i will be willing to try any suggestions.
Posted April 24, 2007 - 07:53 AM
Posted April 26, 2007 - 01:39 AM
Today i put the 168 back in and tried it with my original needle on clip 4.
Still the same but dosent have as much power - i think the other needle gave it a bit of a power boost - im starting to think that the 160 is just perfect with my bike for some reason. Although i then tried running it with the air box cover removed and i think it reved a tiny bit higher before sputtering.
Tommorow i am going to give the air filter a really good clean and go very lightly on the oil and see how that goes, then im going to try the blue needle on clip 3 and see if thats better than the red needle.
If the air filter dosent help then im just going to have to stick with the 160 main and play around with the needle a bit to get some more kick out of it.
If anyone has any ideas please SHOOT!
Posted April 26, 2007 - 04:03 AM
Posted April 26, 2007 - 05:27 AM
i tried adjusting it with the different jet sizes but it liked 1 turn out with all the jets.
Posted April 26, 2007 - 11:23 AM
Posted April 26, 2007 - 08:26 PM
works for me
Posted April 27, 2007 - 06:32 AM
ill do some tests on saturday and see how she goes, ill keep you all up to date.
Posted April 28, 2007 - 06:46 PM
tried the blue needle on clip 3 but i think that was a bit too rich down low so i went with the red needle on clip 5. there was a noticible power increase in mid range when changing my standard needle for red #5.
So thats what i came up with, with my testing.
Posted April 28, 2007 - 08:49 PM
Posted April 28, 2007 - 11:21 PM
Posted April 29, 2007 - 03:17 AM
Posted April 29, 2007 - 11:12 PM
Posted April 30, 2007 - 03:53 AM