Jump to content

Mbiker_101

Members
  • Content Count

    244
  • Joined

  • Last visited

About Mbiker_101

  • Rank
    TT Bronze Member

Profile Information

  • Gender
    Not Telling
  • Location
    California
  1. Mbiker_101

    YZ 1/4 turn race throttle mod

    I can't believe this thread is still going, I wrote this almost 10 years ago. Still riding dirtbikes and loving every minute.
  2. Long story short, i have some gremlins in my o8 wr carb i just can't work out so I'm looking to purchase a used carb off ebay and start from there..I swapped carbs with my friend who has another 08 Wr450 and it ran perfect so I know it's my carb. . I know the WRs have the air cut valve and the yz does not so this would potentially change the jetting. But since the CDI is different on both bikes and the acv is different, would the TPS be set different? I don't want to touch the tps to be on the safe side. Reason i ask is this opens my options for carbs.
  3. Mbiker_101

    08 wr450 Help with carb issues after cleaning

    Ok, so I drained the tank yesterday and removed the petcock to clean the tank and rotote the petcock so it faces the carb to shorten the gas line and remove the fuel filter so we get full gas flow. Went to the local station that sells VP 100 to put fresh gas in for the thanksgiving weekend in the desert.... Well, went for a test ride to make sure bike is 100% and the stumble and rough running is back???? Do you think it was bad gas even tho it was brand new? My thought is since this is 8.99 a gallon it doesn't get rotated often and is bad? Called the station and the owner swears it was new two weeks ago? Is he full of it and it is bad gas or something different with 100 octane? I'm going to drain the tank and put regular gas in to test but i'm wondering if this was the issue all along?
  4. Mbiker_101

    08 wr450 Help with carb issues after cleaning

    Yup, clear one, thought the original could be clogged so i replaced with a new one from cycle gear.... But the new one flowed terrible. Wish i would have just bypassed originally and that would have saved countless hours of troubleshooting. The accelerator pump camoflaged the issue by providing a solid squirt of fuel and when the throttle was constant the fuel line couldn't feed the carb so is felt like it was running out of gas... Well it was... Slowly
  5. Mbiker_101

    08 wr450 Help with carb issues after cleaning

    Finally fixed the issue!!!!! Bad fuel filter!!!! I replaced the fuel filter as one of my first steps in troubleshooting this issue with a brand new filter the same one as before..... The new filter was flowing just enough to feed the carb and flow looked pretty strong but not 100%. I thought couldn't be fuel filter because it,s brand new.... But bypassed the filter and flow seemed much better. Went for a quick ride and much better but not perfect. Once warmed up completly, I adjusted the fuel screw and to my surprise i'm back to two turns out and runs like a champ!!! I spent a ton of time troubleshooting this issue and it turns out it was a simple fuel filter..... But the good news is i went through about every other system and made sure they're 100% so my carb is as good a new and running perfect!!!! Thanks for all the help guys!!! This forum rocks
  6. Mbiker_101

    08 wr450 Help with carb issues after cleaning

    That was one of the first things i tried but that was a month ago, with so many changes i need to recheck.
  7. Mbiker_101

    08 wr450 Help with carb issues after cleaning

    Don't know specific rpm but gues 3000-4000, seems to be worse when warm gas is brand new vp100 octane. Pulled the plug and it looks normal. Going to open up the side to check the stator cables.
  8. Mbiker_101

    08 wr450 Help with carb issues after cleaning

    So i took the bike out for a spin on the street and it's still missing.... Should i focus on electrical now?
  9. Mbiker_101

    08 wr450 Help with carb issues after cleaning

    Called JD jetting and explained my issues and he said it seemed like a fcr mid body issue, he sent me a set of mid body gaskets. Tore my carb apart tonight and look what i found, the gasket was partially blocking the fuel screw hole.... Heres a pic 1. Mid body apart 2. Mid body upper part showing rubber gasket clogging fuel screw hole 3. Up close view 4. With the proper oring
  10. Mbiker_101

    08 wr450 Help with carb issues after cleaning

    Kenny everything you mentioned i checked 5-6 times, and the jets are squeaky clean
  11. Mbiker_101

    08 wr450 Help with carb issues after cleaning

    I've dropped the bike off at a local shop for them to test ride and see if they can determine the issue. In my research i've found out how the air cut valve works and how it makes it run lean or rich. I've cleaned the acv out twice now and noticed it had a very weak spring, is it possible if the acv is opening and closing premature this would explain why i need to turn the fuel screw to three turns out not two as before? If the valve was open like stock it would need two turns out correct, valve closed three turns? But if it had a weak spring it could bounce back and forth at low throttle and cause the weird stutter etc? Just a shot in the dark? I could try to block it like others to see if that helped? Worst case i have my friends 08wr450 that i may steal his carb to test on my bike to quickly tell if its my carb or electrical? Thanks again everyone.
  12. Mbiker_101

    08 wr450 Help with carb issues after cleaning

    Actually thinking about it it is across the board rpm but feels much stronger down low.
  13. Mbiker_101

    08 wr450 Help with carb issues after cleaning

    About 1/8 throttle Both cold and hot New VP race gas Have not cleaned out stator harness plug. But did install new plug. I'll check the stator. Thanks for the quick reply.
  14. Mbiker_101

    08 wr450 Help with carb issues after cleaning

    Ok, I'm ready to toss the bike off a cliff....I've tried all your tips... and i've cleaned the carb 4 times now and still can't get it fixed and the third time even took the carb to the shop to have them double check everything and they said it looks great. Is it possible it is electrical? I've unplugged the tps to check and it doesn't help so that rules out the tps i think? Could it be a coil or something? When i crashed it hit pretty hard and maybe jarred soething loose?
  15. Mbiker_101

    08 wr450 Help with carb issues after cleaning

    Thanks guys, i've followed Krannie's instruction before and after the carb cleaning, Krannie you sent me the JD red needle a while ago and i followed youre jetting suggestions and had the bike running great. I know how to set the fuel screw and i know 3 turns is too much out but still don't understand if i've cleaned everything out to perfection how the fuel screw is now 3 turns outs vs the 2 turns before and running perfect. Is it possible it wasn't that clean before with two turns? Now that i've cleaned it out really well it requires a larger pilot??? Is it possible the float height is off but that shouldn't have changed? i may yank the carb out again to triple check everything.
×