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About mikekx102

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    TT Bronze Member

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    kitesurfing, dirtbike riding, ice skating, photography and cycling =]
  1. Nah the locating pins are still in there, as are the piston pin circlips the gouge lines up with the smeared area on the piston, but not with where the ring end gap should be. I believe the ring ends were in their correct position but aren't sure. I can't find any damage on the piston rings and the top of the piston is perfect in the area above the scoring. I had the cylinder repaired and replated before this top end. I had a new Vertex piston kit matched to the cylinder and installed it straight away, but I didn't check the ring end gap. So the piston was matched to the cylinder but I don't remember checking the ring end gap. I assumed that would have been done by the cylinder repair people, a poor assumption. Also, the oil ratio has been 27:1 with Fully Synthetic Motorex, and Jetted rich (I didn't want to blow it up again). Thanks for the advice on the head. That's exactly what I plan to do
  2. Yeah the chamfers all look and feel identical
  3. So yet again I've had "bad luck" with a 2-stroke top-end. I took my cylinder off to check my big end bearing for play (all looks good) and found that part of the cylinder above the intake port chipped off and messed up the piston and head. Would this be a bad luck story, or have I been doing something wrong? When I rebuilt 4-stroke top ends, its always been sweet. But I seized my KX85 after rebuilding that years ago, sized my 250SX after rebuilding that, and so I sent off the cylinder to get it repaired and replated & matched to a piston kit and this is what it looks like several years later: I'm thinking the cylinder should be sent off for repair and replating again. I'm not sure what to do with the head, but soon I will be doing another top end and this time I want it to work! Looking at generic videos on youtube, these are the things to check are correct to have a healthy top end: - Cylinder is in good condition - Piston diameter is correct for the cylinder - Piston ring gap is set for the cylinder - Piston ring ends are located correctly in piston - Squish is set right (correct thickness gaskets used) - Piston pin circlips are seated and gap is at the top or bottom but not sides - Stator is set right (ignition not advanced or retarded - would cause detonation) - Use fully synthetic 2-stroke oil with high quality fuel - Carb is jetted correctly and there are no air leaks - Reed Valves are in good condition and not currently chipped or chipping - Regularly clean air filter Is there anything I've missed? I think its telling that the ring ends are located at the point where the chip occurred, but the ring ends were located correctly in the piston and i believe the gap set by the people who re-plated the cylinder. I have no idea how many hours it has done but I measured the compression and it still has the same amount as when it was put together ~205PSI. Is compression testing relative to a fresh top end an appropriate way of telling how worn a top end is? Mike.
  4. I've heard you can check for play in the bottom end by pulling up and down on the con-rod and feeling for any play in the big-end bearing, and also by taking off the ignition cover and feeling for play in the main bearings (well one of them). If there is no play by these tests do you just put another top end in and walk away? Would that be risky? My bike is a 2009 model and has never had the cases split before. Many of those years have passed with just a few rides a year and I haven't had an hour meter on my bike. I do know that this has been the second top end the bike has had, the bike is used for trail riding and has only used 1 set of brake pads, the original clutch plates are still in spec, always run good quality oil. I'd guess it has several hundred hours on it though. What are your thoughts? Thanks, Mike.
  5. mikekx102

    Get stock lcd speedo working again?

    Hi, We have a problem with dads bike and are wondering if you can help? Its an 06 CRF450X. I went for a ride on it 4 months ago the bike ran good but the LCD display with the speed and tacho would cut out like it wasnt getting power, and then later turn on and then off and it was all a bit weird. I'm pretty sure the red ignition light was also playing up. Then I went away and the bike wasnt used for approx 4 months and when I started it it would idle but it wouldnt rev properly. The LCD screen wont display anything (not intermittent, it just didnt work) and when it was running the red ignition light seemed to be flashing on and off very rapidly. We replaced the coil and battery (totally collapsed!) and now it runs great, but the lcd speedo doesnt work. We're not interested in upgrading to another one even though the stock one sucks and we just want to get it working if possible. -with the ignition off -with the ignition on -running Where should we start? Mike.
  6. Maybe I should have started a new thread. It was the coil and we've fixed that, but now I've got another problem with the LCD Display - the post above yours. Sorry about that! Mike
  7. Wow. No need to be like that. We replaced the battery and coil and it now runs like new =D Thanks guys! So now the bike runs really well but the LCD screen with the speedo still doesn't work. When we replaced the coil and hadn't put the new battery in, we started it up with the seat off and it ran good and would rev up but the battery was making a clicking sound at some frequency? It was completely collapsed. Anyway I don't know why it was making a clicking sound but its been completely stuffed for a long time and I'm wondering if that could be connected to the LCD display not working? With the new fully-charged battery this is what it displays: -with the ignition off -with the ignition on -just started (extremely dim display and as soon as you get it off idle the screen goes blank) - running This last pic dimly shows something but when riding it its completely blank for 99% of the ride and for the time that it flicks on, the speed displays 0km. only for like 3 seconds of my 1hour ride yesterday did it display my speed properly, but was still flashing on and off. Where would I start with this problem? Thank you so much for your help!!! Mike.
  8. Good to know but its not flashing a code or anthing. Sorry what do you mean by cluster? If you mean the LCD display thing it comes as stock in Australia. New coil is on the way
  9. Hi Guys and Girls, We have a problem with dads bike and are wondering if you can help? Its an 06 CRF450X that will idle but not rev. When I went for a ride on it 4 months ago the bike ran good but the LCD display with the speed and tacho would cut out like it wasnt getting power, and then later turn on and then off and it was all a bit weird. I'm pretty sure the red ignition light was also playing up. Then I went away and the bike wasnt used for approx 4 months and when I started it it would idle but it wouldnt rev properly. The LCD screen wont display anything (not intermittent now, it just doesnt work) and when it was running the red ignition light seems to be flashing on and off very rapidly. I've uploaded a video of what it does here: So you can see it best where dad holds the throttle open and the bike does what it does. Straight after I stopped recording the video fuel in the exhaust ignited and went bang- so I dont think its a clogged carby. It has been acting the same with a new spark plug and new fuel. The picture below shows the coil. That lead looked like it wasnt on properly to me but it wont come off and it wont go on any further, and I cant see corrosion anywhere? Where would you start? Mike.
  10. mikekx102

    Is my clutch gone or just need adjustment?

    I'm having the same problem. Lately my bike has been wanting to nudge forwards while the clutch is in and there's load on the engine even with the lever all the way in. When the bike's in gear and off it doesnt want to roll with the lever in. This has been the case for as long as I can remember. But recently I went for a ride and all of a sudden the clutch started engaging when the lever was almost all the way out. So my issue is similar to the original poster's. I pulled my clutch apart a few months ago to have a look and the basket didn't look terrible - the notches were like 0.1mm? and the plates weren't worn out as far as I could tell. Should I start by back-bleeding the line? I'll try to dig up some pictures of the clutch. Mike.
  11. I used straight 2-stroke oil, not premix sorry. and this was only a small amount. Yes, but I ride like a bat outta hell and I've re-jetted so it’s not lean at all. It never seized when I was breaking it in. it was broken in and seized from too much WFO. how can 60:1 ratio recommended from KTM apply to people riding like a desert racer, and someone just putting around at the same time? So I chose 28:1 **small quantity of oil ** Yep! I love the bike and it’s been going really well =D So yeah guys, the problems been fixed! Mike.
  12. You dont need to on a 250, though I was supposed to bleed the air out of the left radiator, so i'll do that. The procedure isnt in the owners manual and I havent looked through the workshop manual for it, I followed KTM-548cc's method of; "Flush the lower end with diesel fuel.. It's not the oil ratio,but a lean fuel mix for what ever reason.. Then before you do anything else get the float level set to the correct diminsion and assure that you have adequate fuel flow .. When I set a float level I remove the carbureter , remove the bowl, and attach a clean piece of fuel line to the inlet.. Then with carb upside down you can gently blow in the line and feel where the float needle closes off.. The float arms should be level with the edge of the bowl..." from my thread http://www.thumpertalk.com/forum/archive/index.php/t-987515-p-2.html I oiled up the little end bearing and wrist pin thanks thats nice to know, though I do think the new piston has far more play than the old one? No, I'm warming it up and going for a 5 min easy ride then going up steep hills in 4th gear using like 3/4 to full throttle in mid revs to bed the rings in. Doing heat cycles is just a waste of precious ring breaking in time in my opinion. What is it done for? to heat treat the piston? because thats already done in the factory. The first 2-stroke i seized was on the first ride after doing heat cycles because i didnt know any better and now that i'm doing the above break in ^ with acceleration, deceleration and varying revs the bike seizes on the 2nd ride but thanks Mike.
  13. mikekx102

    ******* Neighbors -___-

    i cant stop laughing
  14. the first seize was on my kx85 and the second was on my 250SX. The reason the 250SX seized (i think) was the piston was a size 2 and cylinder was a size 1. By seize I mean piston sticking to cylinder. Thanks for the replies
  15. Hey guys, I’ve just finished rebuilding my 2009 KTM 250SX and it fired up first kick (then I turned it off). I’ve done 2 rebuilds on my smokers and seized both the first time I’ve hammered them in the powerband for a few seconds and I want to make sure that doesn’t happen again, so here’s what I’ve done and can you tell me if I’ve done anything wrong or still need to do something: • The bottom end has been flushed out completely of metal particles from the last seize and there’s no play in the bearings and they all turn smoothly. I left a small amount of premix in the bottom end. • The cylinder has been repaired and re-plated by millennium, then matched to a size 1 vertex piston kit. • The rings are in the piston with the “N” marking facing upwards, with the correct ring gap and the pin is in the gap of the rings. • The arrow on the piston is facing the exhaust port. • The powervalve is cleaned and adjusted so that it can’t hit the piston, and it moves easily. • The x-dimension is set by using the correct base gasket and I coated the gasket with a small amount of grease so it should seal. • It has coolant, transmission oil and semi-synthetic oil in the fuel at a 28:1. • The main jet is a #170 and the float height has been set so that its level with the edge of the carb. • The exhaust and intake are sealed and shouldn’t cause an air-leak. 3rd time lucky… Mike.