Jump to content

Maiphut

Members
  • Content Count

    46
  • Joined

  • Last visited

About Maiphut

  • Rank
    TT Member

Profile Information

  • Location
    Australia
  1. Maiphut

    2002 YZ 125 Sprocket

    Try some green grass area, get good traction and easier on the body when you loop out. Don't hold back on the throttle either or your body position, you need that front mud guard right up in your face where you can't see straight ahead for the balance point. Practice, practice. You'll get it eventually. Some bikes are easier to do it than others due to their power and everything else.
  2. Maiphut

    2002 YZ 125 Sprocket

    Tried on pavement? You'll hook up better with a bald tire. Just update your hospital cover before you do.
  3. Maiphut

    2002 YZ 125 Sprocket

    Get your butt all the way back and the way you describe should work easy. Unless you got a bald rear tyre or something, loosing too much traction. Keep trying you'll get it.
  4. Maiphut

    Does my YZ250 need a new bottom end?

    Try some heat on those stuck bolts mate. Even put the case in the oven warm it up, might help.
  5. Maiphut

    2006 yz450f backfiring

    Great stuff! Easy done and have you tearing hair out looking at cam timing, Jets, air leaks and voodoo magic.
  6. Maiphut

    2006 yz450f backfiring

    That would be your problem. Slide plate upside down, it will run with a lot of popping. I've made the mistake in past, easy done.
  7. Check throttle slide plate not upside down and the seal is good.
  8. Maiphut

    Premix Ratio Richer Vs Leaner

    I've run into this problem often with people swearing black and blue running more oil in the mix makes the fuel/air mix richer then wondering why it's got a high hanging idle and not running right amongst other things. Seems a common misunderstanding.
  9. Maiphut

    06 yz450f engine noise

    They are a noisy engine for sure. Also your bottom end could be due for replacement, they do wear out. Pull the top end off and check for any vertical movement in the con rod.
  10. Maiphut

    YZ450FR 2003 Jetting query

    Thanks for ideas. Renewed float valve. Will double check that. The choke.. an area I haven't looked at. On cold start up with choke on it idles ok until it hits operating temp, then with choke off after a minute, high hanging idle to stalling, backfiring. The spark plug is black, this is without doing any plug chops as I can't get a consistent rev range without it stalling on it's own at low revs with the idle screw bumped up even so it hunts between 4k and pop dead. I will look deeper into this ie the start jet/pilot air jet. You've given me a few ideas thankyou. Possibly I missed some crud or stale fuel on the starter jet and or pilot air jet. Or it's picked some up since rebuild. I've renewed tank filters, new lines throughout. Thankyou for some ideas High On Octane, much appreciated. Thought I shouldn't have go that lean on pilot with only a ported head. Had the bike since new so it's stock ex the ported replacement head. Something else isn't right. Cheers
  11. Maiphut

    YZ450FR 2003 Jetting query

    I've put new slide seal in, needle I've tried standard middle, two position richer(blew black exhaust on accell) now 1 position leaner. Accelerates nicely and runs fine up top on 165 main. I've renewed exhaust gaskets at head and mid joint, repacked muffler. Renewed carb boot to intake, checked hot start(new factory seal) also. Float lvl checked. Fuel screw renewed. I've tried every pilot from 50 down to current 38 which is giving me improved starting, less backfiring on closed throttle/idle and less erratic idle/stalling. I'll get hold of some leaner jets I guess and give that a try. Thanks!
  12. Maiphut

    YZ450FR 2003 Jetting query

    Thanks for the reply, I've tried stock, tried richer in stages up to 50 pilot and 170 main making it worse. Hard to start, high hanging/erratic idle, lots of backfiring, stalling. I thought would need richer too, doesn't seem to be the case.
  13. Hi, so I rebuilt my 03 with a wrench rabbit kit and a cylinder works barrel/piston kit, with a nitro4strokes ported complete head. The initial failure was due to a .6mm undersize replacement piston supplied by Yamaha Australia(double check all parts lesson learnt) giving the valves a touch up and the rest yea grenade. Split barrel. So off to another decent shop as I need a new head, can only get factory which is $1800 Aud less cams and valves etc as they all destroyed. Looking at $4500-5 for shop to do it. No way so after spending a lot of hours here reading all the great knowledge and being a maintenance fitter thought what have I got to loose. Found nitro with head for just over 1k aud delivered so was good to go and is a top notch head no complaints. Except I forgot to declare it for customs as it was over 1k by $24 aud. Ha got slugged holding in storage while I emailed a form out to them etc so another $300 on my end for customs .. lesson learnt .. again. So once I had it all together start of this year ready to fire I had all standard jetting for the FR(euro) model, 42 pilot, 165 main etc. Fired up 5th kick and ran like a champ. Very happy. I got to about 8 engine hrs and winter come in so was 10c average, had high hanging idle, blip throttle no load pop like a firecracker, hold hot start to start it after 50 kicks. It got worse over last 6 months. So reading up all the things it could be on here thanks to all I have gone through all and replaced/cleaned etc them and think I'm now on the right track. Firstly I, replaced hot start O-ring, All balls carb kit and full carby clean. Gone richer in stages from stock to a 48 pilot and 170 main but ran like a dog and black exhaust fumes chalking out on accell. Today I got my leaner pilot jets in #40 &#38. I put the 40 in and fired up easily and noticeably less popping but not like stock when I bought it new. Same again for 38, better symptoms again and idle is a bit more stable, but not rideable as hunts around 1700-3k and stalls easily. With stock 165 main and needle jet. I've found some info regarding ported heads(not much) on yfz450 quads that they had to go leaner in the jetting. So I guess I keep going leaner on the pilot. My altitude is sea level, no humidity and 30-40c atm. I'm thinking the extra flow through the head is dragging more fuel in. Any thoughts or help appreciated. Cheers
  14. Maiphut

    Run a kickstand on YZ450F

    I run a Trailtech stand. Been the bees knees so far don't even know it's there until I want it.
  15. Maiphut

    Simple Green ???

    I'll have to look into that spray nine, thanks all
×