Jump to content


  • Content Count

  • Joined

  • Last visited

About Thumpermx

  • Rank
    TT Member

Profile Information

  • Gender
    Not Telling
  • Location
    United Kingdom

Recent Profile Visitors

118 profile views
  1. I was having trouble with the bike. it started fouling plugs, so I sent the carb to a mechanic with a rebuild kit. He rebuilt it, said it was fine. My bike would always start first kick, run for a bit and then die and would not start again. I replaced the cranks seals, new reeds, re wound the stator motor. Still the same thing, run it round for half a day, then it would start to foul the plug, and I was on a big open track leaving it in a gear down just to keep it revving all the time, in case it was all clogged up. Still had the same issues, bike would start first kick after being sat for a while, then wouldn’t start again after it died 20 seconds later So I thought I would do the top end incase fuel is getting past the rings or something, and here we are
  2. Regardless, both my clips I put in were still in, so this circlip must have been pre existing which is strange
  3. I protected the bottom with a towel as I was doing it, every piston kit I’ve ever had when my dad used to do it never had new circlips, so I assumed you had to re-use the previous ones like every other time before
  4. Ok, kinda confused now barrel was fine, not scored piston has had chunks taken out of it, but the clips are still in? The hell did that other clip come from, I have no idea
  5. Ok thanks, just a mention I’m actually trying to sell this bike, thought I would freshen the top end up because it wasn’t running well, so all I need to do is get it going and then will sell immediately, will this affect what I should replace also I have limited time, once a month max I come back to where the bike is stored to see my family, so I have only a morning each time, is it worth buying all the tools or just getting a mechanic to do it? Thanks
  6. So, worse than we thought Found a clip loose at bottom of cylinder, the piston moves freely in the cylinder but the bottom end is totally locked up I don’t know why there was a clip, I put them back in by hand making sure not to bend them and they were both sitting at 12 o’clock So I’m guessing allot of money involved in the next step? Splitting cases etc Thanks, Dan
  7. Ok, that’s interesting, yes it was idling for approx 5-6 then stopped, I installed the piston with the arrow facing towards the exhaust, the circlips I definitely put in as I had to re use the previous ones, I oiled the cylinder before installation and pushed the piston with ring on through it, the rings I installed with the marking near the ring gap facing upwards I will take it back apart tomorrow and post pics on here Thanks
  8. What is the max difference you can have between being just right and too big?
  9. Was the +.01 far to big? Ok thanks
  10. Hi everyone I just fitted a new piston and rings into my yz 250, I ordered the D piston as this was the letter printed on my cylinder I have very limited tools and very limited time, so I have just finished fitting the new piston after oiling it with 2 stroke oil and making sure it passed through the cylinder smoothly the only thing I was slightly concerned about when I replaced the piston was that the old piston read on top 66.35 and my new one read 66.36. I asked my friend for advice he said the difference is miniscule this is were I feel I went wrong and should have looked it up in more detail, for when I started the bike up it ran and was ticking over and then suddenly stopped. This was typical with my bike, so I started it up again. Again, it ran and then suddenly stopped. This time I thought there was something wrong by how sudden it stopped. Sure enough, when I tried to push the kick start with my hand it wouldn’t move. So I’m guessing the 0.01 increase was too big, and as it heated up and expanded it has seized? Has this taken out my cylinder bore too? My mechanical knowledge is very limited and I’m kind of kicking myself for taking my friends advice Any help would be appreciated, thanks
  11. A little update changed the reeds for new ones today, just to see if there was a problem there, old reeds looked ok but changed them anyway to get to one of the bolts out to get to change the reeds I took the exhaust off, and jeez I turned it over and a LOAD of fuel came out the pipe now, am I right in saying this is unburnt fuel, and it is getting through because something in the carb is either stuck open or incorrect? any thoughts appreciateed, thanks
  12. I’ll be dead honest, I was not a fast rider and was riding tight slow track, so i thought it was purely because I was not on the pipe enough, nothing worse than wasting someones time it’s horrible
  13. Could it be the stator motor? one other weird thing is if I leave it for a long time sometimes then come back to it it starts first kick long time being 2-3 weeks
  14. Been the same oil since I’ve had it 40:1, always run the same super unleaded, the air screw I was hoping the mechanic set up right but maybe that’s something I can look at again yeh she’s not happy, but then again I like riding my bike not looking at it in the garage so I needed the ktm, it’s her own fault hah Just ordered new reeds, might aswell rule that one out aswell
  • Create New...