Hi, I’ve recently bought a kart for my wife to try out and see if she likes it…I got a great deal on a recent Praga with a HPV motor plus a spare one, which I’m rebuilding. They both have a new style clutch and I can’t seem to find any specs for that clutch…is it the same used in the Leopard? In particular, I’d like to know the max acceptable wear on the friction hub and how to tighten the starter nut and its torque…I’m not a fan of using impact drivers on crankshafts
Does anybody know?
I don’t know about the maximum wear or nut torque but I am pretty sure it’s the same as the leopard, the x30 and now the ka. On my kpv I just clean all the treads with break clean and give a couple hits with the small impact. Always did the same on my kt100, never any problems
Thanks!
I checked the leopard manual and used those specs for the wear limits and used an impact. All good, I’m curious though to see if the friction hub is interchangeable with the leopard…
Not positive about that but I am almost 100% sure the driver is interchangeable
Sorry to thread jack!
My son has a older hpv/kpv the clutch i thought was same as the 09 leopard 125cc tag motor one but it a clutch drum without removable driver like on that one so I bought driver for that which will not work. Can I switch drum to new one that can use the removable driver or do I need a whole new clutch. The drum has a 11t on it and everyone at our track says need a 10t so want to figure best solution to switch it. I cant find the drum with driver on it alone. thanks again sorry such a newb. Family loving it though having blast thanks to everyone in this industry amazing group of people! We hope to try a little club racing next year continue growing!
Sounds to me like you have the old style clutch on the motor, driver and drum are one piece, uses friction disks, and you bought a driver for a new style clutch. No parts that I know of are compatible between old style clutch and new style. New style utilizes a shoe style clutch to engage. I recommend next time you have the motor freshen up to replace with new style clutch. Performance should be about the same but with the new style replacing the drive sprocket will be substantially cheaper.
If the only problem is the gearing,you may well be able to correct using a bigger rear sprocket.
On our tracks in UK we would expect to run around 10-80 but 11 -88 would be an exact equivalent.
Obviously the sprocket is nearer the ground, and it may be that your particular track needs lower gearing. Just check what rear sprocket the front runners are using with their 10t front ,add 8t, and fit if practical for now at least.
Sweet thanks guys! Really appreciate all the help!
I had a clutch question my son was driving monday and his clutch started making a metal banging noise and stopped working when wheels off ground spins fine no noise just when load. Did clutch break or could the woodruff key have broke?
Could have sheared the key off. Only way to really know is to take it all off and look at it.
Ok will do thanks! One more question if i do just need to replace it do i need to do whole lapping compound think or just replace and reinstall? Was told should use lapping compound when replacing clutch so beds in properly.
Highly recommend lapping as the taper is what’s meant to transmit the drive, rather than the key.
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