mayday Posted November 15, 2015 Report Share Posted November 15, 2015 So, new member, new to me bike (loving it!) - bit of a back story - gear up to go for a ride, kick it over, and she proceeds to SCREAM full RPM (turns out the throtttle slide wasn't seating fully) - of course my kill switch chose that moment to stick, so took a few minutes to get the fuel turned off, bike finally dies. After teaching the neighbourhood children a few new curse words, got things sorted out, but when I tried to re-fire it, kicking it was as if there was no compression - turned over way too easily. Took it apart and found what I think is the problem - the primary gear nut was loose, and the locking washer bent out. So, my question to the masses, since I've searched to no avail for a shop manual for this bike - I'm guessing I should be able to re-torque the nut (120N/m), new lock washer, new case gasket (assuming I can find those) and Bobs Your Uncle? Anything else I should be looking for/doing while I've got it open? Quote Link to comment Share on other sites More sharing options...
copemech Posted November 16, 2015 Report Share Posted November 16, 2015 I suppose your red mark indicates the one? If so, it has a woodruff key in there I would presume that is also sheared. Prey that is all that is wrong and you did not scorch the piston as well. Quote Link to comment Share on other sites More sharing options...
mayday Posted November 16, 2015 Author Report Share Posted November 16, 2015 Hmm, hadn't thought about a key - makes sense I guess - although of course now it means I have to pull the clutch basket, pull the primary gear :-( Quote Link to comment Share on other sites More sharing options...
mayday Posted November 16, 2015 Author Report Share Posted November 16, 2015 Well, this process has been informative if nothing else! Just an FYI for anyone else who goes through this - nope, no key - after pulling the clutch basket, then primary gear off, found it's a tapered shaft. Let's see what happens when I put it all back together. Quote Link to comment Share on other sites More sharing options...
collyolly Posted November 17, 2015 Report Share Posted November 17, 2015 Have you found out why there is no compression, the lack of flywheel should not stop your compression. Take out the plug and turn the engine over by hand with your finger tip over the plug hole to make sure there is something going on in the top end. Quote Link to comment Share on other sites More sharing options...
feetupfun Posted November 17, 2015 Report Share Posted November 17, 2015 Well, this process has been informative if nothing else! Just an FYI for anyone else who goes through this - nope, no key - after pulling the clutch basket, then primary gear off, found it's a tapered shaft. Let's see what happens when I put it all back together. Montesa Cota 247, 348 and 349 also drive the primary gear with a taper Quote Link to comment Share on other sites More sharing options...
2stroke4stroke Posted November 17, 2015 Report Share Posted November 17, 2015 In this instance a key would serve no purpose as it does not matter where the gear lines up. With an ignition flywheel the key is solely to align it correctly for timing and does not bear a load, as you find out if the nut comes slack - it is the taper that holds the item in place. Quote Link to comment Share on other sites More sharing options...
mayday Posted November 18, 2015 Author Report Share Posted November 18, 2015 Have you found out why there is no compression, the lack of flywheel should not stop your compression. Take out the plug and turn the engine over by hand with your finger tip over the plug hole to make sure there is something going on in the top end. No, the OTHER side of the bike :-) When you push on the kick starter, it pushes on a small gear, that pushes on a larger gear attached to the clutch basket, which finally pushes on a medium gear which with the taper fit, turns the crank. So when I finally tightened that nut, the piston goes up/down. Unfortunately since I went searching for a key that wasn't there, I ended up having to take off the clutch basket - and since I'm a degenerate "don't want to buy any specialty tool I can't Redneck something I already have to use instead" - I now have to buy a whole new clutch basket, as my Redneck clutch basket Holder" only ended up breaking off a tang on the outer basket :-( Quote Link to comment Share on other sites More sharing options...
zippy Posted November 18, 2015 Report Share Posted November 18, 2015 since I'm a degenerate "don't want to buy any specialty tool I can't Redneck something I already have to use instead" - I now have to buy a whole new clutch basket, as my Redneck clutch basket Holder" only ended up breaking off a tang on the outer basket :-( I have been there before...............with similar results. As a late teen/early 20's I used a pry bar to hold an S-10 (small truck) serpentine belt tension pulley back. Promptly snapping the arm of the tensioner off. When buying new one at the dealer ($$$$$$$$$$) found out there is a little square inset in the arm that a ratchet/breaker bar would fit into and then pull back on the arm without breaking it........................... 1 Quote Link to comment Share on other sites More sharing options...
dan williams Posted November 18, 2015 Report Share Posted November 18, 2015 I have a couple clutch baskets gathering dust in the garage. Want one? They were going to be part of a plating experiment I never got to. I think I've got the rivets somewhere too. Quote Link to comment Share on other sites More sharing options...
italianstallion Posted November 18, 2015 Report Share Posted November 18, 2015 Had a similar problem on my rev3 recently where the nut had become loose on the primary gear resulting in no compression on kick. I believe bvm retorqued it and added a tiny tiny bit of thread locker. Mechanic commented that he'd never seen this issue before... Quote Link to comment Share on other sites More sharing options...
mayday Posted November 19, 2015 Author Report Share Posted November 19, 2015 I have a couple clutch baskets gathering dust in the garage. Want one? They were going to be part of a plating experiment I never got to. I think I've got the rivets somewhere too. PM sent! Quote Link to comment Share on other sites More sharing options...
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