plymo Posted January 24, 2019 Share Posted January 24, 2019 I've got a KM Baja that just refuses to move! Basically it looks as if the clutch isn't engaging properly and slips far too much. I've checked all the usual stuff, the engine runs nicely and the diff turns smoothly. When it's off the ground I can get the wheels to turn very quickly, but even on a very smooth surface it barely moves as the clutch just slips. I've already put on a standard set of clutch shoes and spring, new clutch bolts as well and a new standard clutch bell. I've also tried reversing the clutch shoes as I've had good results with this on nitro cars but still no joy. I've also tried having the clutch shoe bolts fairly loose in case it was sticking on that but that hasn't worked either. Does anyone have any ideas? Thanks Quote Link to comment Share on other sites More sharing options...
Oh How Original Posted January 24, 2019 Share Posted January 24, 2019 Have you checked the dog bone for snapped pins? Quote Link to comment Share on other sites More sharing options...
KORB Posted January 24, 2019 Share Posted January 24, 2019 2 hours ago, plymo said: I've got a KM Baja that just refuses to move! Basically it looks as if the clutch isn't engaging properly and slips far too much. I've checked all the usual stuff, the engine runs nicely and the diff turns smoothly. When it's off the ground I can get the wheels to turn very quickly, but even on a very smooth surface it barely moves as the clutch just slips. I've already put on a standard set of clutch shoes and spring, new clutch bolts as well and a new standard clutch bell. I've also tried reversing the clutch shoes as I've had good results with this on nitro cars but still no joy. I've also tried having the clutch shoe bolts fairly loose in case it was sticking on that but that hasn't worked either. Does anyone have any ideas? Thanks A bit obvious but have you checked that the wheels turning freely (together) by hand ? If not, they could be on too tightly. Quote Link to comment Share on other sites More sharing options...
plymo Posted January 24, 2019 Author Share Posted January 24, 2019 Cheers for the replies, I've made sure there's nothing wrong on the drive side that all runs smoothly. The clutch does engage if I lift the wheels off the ground and it spins the wheels very quickly, but if I put it back down it stops and the clutch just slips. There's some glazing on the clutch shoes after each test, I've been sanding that off gently is that the right thing to do? Quote Link to comment Share on other sites More sharing options...
spents Posted January 24, 2019 Share Posted January 24, 2019 as above mate, check dogbone pins, also check the internal drive pins in the diff, and the gearbox output/layshaft pin inside the gearbox, not sure what clutch bell the km uses, but on the hpi baja there was a weak point on the stock bell, the main shaft ( the bit that runs through the bearings and has pinion on the end) was welded to the bell and the weld could fail causing the bell to just spin with hardly ant drive to the gears , Quote Link to comment Share on other sites More sharing options...
Oh How Original Posted January 24, 2019 Share Posted January 24, 2019 The wheels could still spin if you're missing just one or two pins. I've had the exact same thing, I'd put money on it not being the clutch. Quote Link to comment Share on other sites More sharing options...
KORB Posted January 24, 2019 Share Posted January 24, 2019 Can you put a video up? Clutch - gears etc Quote Link to comment Share on other sites More sharing options...
mark35 Posted January 25, 2019 Share Posted January 25, 2019 My mates rig had I problem That sounds like the one you have, his turned out to be the clutch mount, it was worn and spinning on the crank, this problem would also happen if the mount bolt was loose. Give that a try if you have not sorted it yet? 1 Quote Link to comment Share on other sites More sharing options...
plymo Posted January 28, 2019 Author Share Posted January 28, 2019 I've now gone through and double checked the setup from the wheels to spur gear and it all seems fine, also checked the clutch mount and that was all nice and tight. I had a go at running it with no spring on the clutch, of course it was basically undriveable but it did manage to actually move, and the clutch didn't slip. It seems as if the spring is too strong and is stopping the clutch engaging hard enough. The problem is the spring is a new one 6000rpm and the old one didn't work either, so I'm a bit stuck. Is it possible to loosen the spring? Or to get an even softer one? Quote Link to comment Share on other sites More sharing options...
spents Posted January 28, 2019 Share Posted January 28, 2019 (edited) a 6k spring should be fine mate,, a lot of people, myself included use an 8k spring, if you've tried 2 different springs then cant really see it being the spring at fault, something else though, have you got the right clutch bolts for your clutch ? a Zenoah style clutch uses 8mm bolts and a cy style clutch uses a 9mm bolt, what I mean is the smooth step that the clutch shoe pivots on is either 8 or 9mm , if your using a clutch with a 9mm hole with an 8mm bolt then the clutch wont work properly, easy mistake to make but also an easy fix, you don't want a spring with too low an engagement point either cos all the power on these 2 strokes are higher in the revs, it has to be something simple though cos you've ruled out everything else by the sounds of it, edit; you are using all the clutch washers as well aren't you ? spring washers on the outer side and the spacer washers on the inner engine side, Edited January 28, 2019 by spents Quote Link to comment Share on other sites More sharing options...
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