screeching sound when idleing, stalls out the engine.

[mark20]

well, i bought me a 4 stroke kit, its been very reliable, but there is one problem with it.

sometimes when the bike is idling the bike suddenly has a screeching sound and stalls out the engine (clutch seems like its fully engaged when it happens)

its driving me crazy! ive took it apart, oiled the bushing and nothing.
has anyone had this happen to them?
still trying to figure out why its doing it. (im considering trying to lightly oil the pads, but thats a last resort)
everything tight, clutch packs look fine.

running out of ideas

also, it works just fine when your moving, nothing wrong with that.

 

[The_Aleman]

It's very important that the clutch is securely on the shaft on the keyed-shaft engine and doesn't move on the shaft itself. If it can move at all, it can cause problems like you're experiencing. The clutch itself has a rather primitive design, relying on sliding surfaces.

Take apart your clutch and clean it thoroughly with a wire brush. Lightly grease the sliders between rotor and clutch shoes and bevel the sharp edges off the shoes with a file. If your clutch doesn't need engagement point adjustment (bike doesn't try to move on it's own at idle), reassemble the clutch.

If engagement point adjustment is needed, you can use thin washers between clutch springs and rotor to increase the RPM at which your clutch achieves lockup. This increases the effective spring strength. Better yet, replace the springs with stronger ones.

Check your clutch drum for any unusual wearing or high spots. Clean it well, steel wool works well here. When you're ready, secure the clutch back on the keyed shaft. Make sure it doesn't move! You may need to cut/file your own custom key like I did. Insert bushing into clutch drum and lightly oil the shaft and inside of bushing with a decent quality oil. 3n1 or Zoom Spout works great here. Make sure drum turns freely around the clutch and doesn't bind anywhere.

Start it up and see if it's improved! Try to avoid long periods of engine idle at a stop, this cooks off the oil on the bushing. I used to keep mine oiled by putting a few drops on the exposed flange right after a ride while it was nice and hot. The bushing will soak up the oil. A real Oilite bushing is better than the one that comes with the kit, they can be found at McMaster-Carr for pretty cheap.

 

[mark20]

It's very important that the clutch is securely on the shaft on the keyed-shaft engine and doesn't move on the shaft itself. If it can move at all, it can cause problems like you're experiencing. The clutch itself has a rather primitive design, relying on sliding surfaces.

Take apart your clutch and clean it thoroughly with a wire brush. Lightly grease the sliders between rotor and clutch shoes and bevel the sharp edges off the shoes with a file. If your clutch doesn't need engagement point adjustment (bike doesn't try to move on it's own at idle), reassemble the clutch.

If engagement point adjustment is needed, you can use thin washers between clutch springs and rotor to increase the RPM at which your clutch achieves lockup. This increases the effective spring strength. Better yet, replace the springs with stronger ones.

Check your clutch drum for any unusual wearing or high spots. Clean it well, steel wool works well here. When you're ready, secure the clutch back on the keyed shaft. Make sure it doesn't move! You may need to cut/file your own custom key like I did. Insert bushing into clutch drum and lightly oil the shaft and inside of bushing with a decent quality oil. 3n1 or Zoom Spout works great here. Make sure drum turns freely around the clutch and doesn't bind anywhere.

Start it up and see if it's improved! Try to avoid long periods of engine idle at a stop, this cooks off the oil on the bushing. I used to keep mine oiled by putting a few drops on the exposed flange right after a ride while it was nice and hot. The bushing will soak up the oil. A real Oilite bushing is better than the one that comes with the kit, they can be found at McMaster-Carr for pretty cheap.

I ended up fixing it, there was this rubberized plastic type of thing between the bushing and the shaft (im assuming burned assembly paste)
Oiled the bushing with compressor oil, works like a charm now!