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pokolbinguy last won the day on January 9

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About pokolbinguy

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  • Location Pokolbin NSW, Australia
  1. pokolbinguy

    YFM250 Moto 4 - Breathing new life.....help?

    So I got a new Starter cap today (part #9 on diagram), but still waiting on the new springs (part 8), I have the original three springs but figured they were the weak link in the chain so worth replacing....BUT they are coming from Japan and I won't have them until next week at least and I was hoping I might be able to get the old girl running sooner than that, so I thought I would put the starter clutch back together using the old springs. For the sake of it some photos attached to show the Starter clutch fitted back to the fly wheel to show it all ready to roll. However, when I attempt to install the fly wheel / starter clutch on the bike one of the little dowels keeps falling out. VERY frustrating. Am I right to think the springs need replacing and they are "lazy" ? Therefore they don't apply enough pressure on the dowel pin within the clutch plate to hold it into position as the flywheel/clutch is installed? Or am I just not doing it right...is there a trick? Any suggestions? Cheers, Pok
  2. pokolbinguy

    YFM250 Moto 4 - Breathing new life.....help?

    Nice ! if I can get them I may as well replace the springs while I am at it. I figure they are really the only parts that can fail?
  3. pokolbinguy

    YFM250 Moto 4 - Breathing new life.....help?

    So I had a partial win after a dig around in the 'bucket of parts' (mainly bolts etc) that came with the Quad. I found most of the parts for the starter clutch, well I think so anyway, (photo below)....but missing one part (Grrrr!!!) - 1 x 'CAP, STARTER CLUTCH SPRING' (part 1J7-15583-01-00). Hopefully I can get my hand on this. Partzilla shows it as available so hopefully available in Australia as I am sure it will be cheaper than replacing the whole clutch assembly if I can get away from it. What I didn't come across, and not sure if I need them or not are the unknown parts that are shown on the exploded parts diagram (see below as "What is this?) - When I have looked at photos of the Starter clutch on line, replacement parts etc there doesn't seem to be any other parts? Also, am I correct that the dowel pins are out of scale in the exploded view? I assume they are the the parts I have marked in my photo below and not another part that I require??? Cheers, Pok Link to Partzilla with parts diagram as per below - https://www.partzilla.com/catalog/yamaha/atv/1991/moto-4-yfm250b/starter-clutch
  4. pokolbinguy

    YFM250 Moto 4 - Breathing new life.....help?

    Rightio so I got the fly wheel off behind the generator and removed the starter clutch...... Ummmm....See photo. Where at the internals of the clutch? Springs etc? Seems someone must have had issues with the clutch in the past so has removed the workings of it. Damn...Now I have to replace them / it. In the mean time, is anyone able to explain in layman's terms how this clutch works? there doesn't seem to be anything to physically engage the cog (aka Cog #2 in previous post) when the starter motor runs? How does the magic happen? Cheers, Pok
  5. pokolbinguy

    YFM250 Moto 4 - Breathing new life.....help?

    Thanks for the point in the right direction. Sounds like I need to the rotor/flywheel off. Any tips? Surely the rollers / springs can be cleaned up instead of replacing the whole clutch?
  6. pokolbinguy

    YFM250 Moto 4 - Breathing new life.....help?

    Looking at these links; https://www.partzilla.com/catalog/yamaha/atv/1991/moto-4-yfm250b/generator https://www.partzilla.com/catalog/yamaha/atv/1991/moto-4-yfm250b/starter-clutch I assume the 'starter clutch' sits behind the generator rotor assembly? Surely the original clutch is still in position and just needs freeing up?
  7. pokolbinguy

    YFM250 Moto 4 - Breathing new life.....help?

    Spark Video if interested. spark_baby.mpg
  8. Hi All, Following on from the brief interlude in the "introducing myself" thread.... In a nutshell, I acquired a YFM250 Moto 4 (1991) for cheap recently with the previous owner citing "no spark, needs a new magneto coil and I don't have time to fix it"... anyway I am dubious that the magneto/generator is the issue and thinking more along the line of ignition coil as after a clean up of the magneto I was able to get a rather decent voltage reading off the magneto with pull start and resistence readings seem to check out that the magneto is all ok (all 3 x phases = 1.2 ohms and no run to ground) None the less I ordered a new Ignition coil and Magneto/generator coil and am waiting for them to arrive. In the mean time I cleaned up the current Magneto, popped in a new battery and sparkplug, checked out all the wiring harness, all seemed good except I came across the "neutral switch" wire was broken. After wiring up a new neutral switch wire, the neutral light now comes on (small win) and the starter relay (attached to rectifier) now clicks. If I hit the starter switch on handle bar the starter motor spins and if I pull the cord starter I get a spark on pull....YAY!! I'll try and attach a video below if possible. So onto the starter motor. Starter solenoid seems to work A-ok, even if it looks crappy and starter motor spins as it should when I hit the start switch....but here is my issue. When the starter motor runs it turns Cog #1 and Cog #2 (see photo below)....but the chain in the back of the starter which I assume is the timing chain, does not move and there is no apparent movement of the piston in the cylinder. If I turn it by hand (per photo) or with the pull starter however the chain moves and the engine turns. However cog #2 rotates but not fluidly with the "Crank" (part I turn by hand) for the lack of a better word to use if that makes sense? Is there a grub screw or similar on Cog #2 that fixes it to the center shaft to make it all turn when the starter motor is run? Could there be a part missing? Previous owner had the starter apart so could be possible? The outer/front part seems to be on a key-way so not sure how to remove this easily to check how Cog #2 is attached. What am I missing here? spark_baby.mpg
  9. pokolbinguy

    Introducing myself

    What is a simple way to test the solenoid?
  10. pokolbinguy

    Introducing myself

    Yeh the Starter motor solenoid looks pretty crappy (photo attached). With jumping the starter relay, I assume it is just a matter of crossing the 'in' and 'out' wires, for the lack of a better term... e.g. not the neutral or brake safety switch wires ? I am located in Australia, so finding some parts is a pain in the butt. However I was thinking of buying the following starter solenoid; https://www.ebay.com.au/itm/AFTERMARKET-STARTER-SOLENOID-YAMAHA-YFM250-1989-to-1991/272348129240 and I came across this CDI but I am not sure on it...seems to cheap to me. https://www.ebay.com.au/itm/High-Performance-Ignition-Coil-CDI-Box-For-86-91-Yamaha-YFM-225-250-Moto-4-AU/202471978714 When you say the 'Caltrec' ones don't work so well, what are the issues? or just un-reliable? Cheers, Brett
  11. pokolbinguy

    Introducing myself

    Condition pretty good over all. Frame and suspension suggests it has not done al ot of work but won't give spark. Wiring harness seems to check out. I ran a multi-meter over the stator coil. All three phases came back with the same resistance (1.2 ohms) and there didn't seem to be any shorting to ground. From what I have seen online this suggests the stator coil is all ok? Starter solenoid is pretty corroded and shot I think but the 'neutral' switch wire was disconnected and looking at the wiring diagram I think the starter solenoid will not function unless there is power from the neutral switch (?). Starter motor spins over when connected to battery directly but doesn't sound like it is "engaging" as the engine doesn't turn over...need to check out what is going on there but if I can get it to pull start then atleast that is a starting point (no pun intended) I think the ignition coil is busted though as resistance on the ignition coil seemed through the roof so this seemed like a logical issue to me but I am no mechanic or auto electrician so happy to be proved incorrect. I have not yet checked out the Regulator or starter circuit relay and I believe it is not possible to test the CDI? Am I on the right track???? Cheers.
  12. pokolbinguy

    1986 Yamaha Moto 4 Air Filter Box

    Got to love youtube
  13. pokolbinguy

    Introducing myself

    Sounds familiar. Scored myself a 1991 Moto 4 YFM250 .... not to get it to run. Doesn't spark, previous owner thinks it is the stator, i'm not convinced, I reckon it is the Ignition coil. Now the fun begins.
  14. pokolbinguy

    1987 Yamaha moto 4 will not start

    How did you get on?
  15. pokolbinguy

    1991 Yamaha Moto 4 Service Manual

    Ooo looks like what I need (I hope)