Recently when trying to start my bike, I release the clutch and the rear wheel locks up, unable to turn the engine over. This happens about five out of six times. In the past, the bike always had enough momentum to keep the engine turning over as long as it was rolling. When I took the plug out, I could turn the engine over manually. Any ideas what might be causing this provblem?
Engine Will Not Turn Over
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What engine do you have? Did it ever run? How fast are you pedaling before you release the clutch?
Give us some information to work with and we'll try to help.
Tom
Give us some information to work with and we'll try to help.
Tom
Heck - sounds to me like you've just got a lot of compression. I wish I had that problem. Maybe pedal faster before you drop the clutch.
DuctTapedGoat and 2door, thanks for your replies. I have an 80cc HT engine from King's Motors. In the past, even pedaling slowly would turn the engine over. Now no matter how fast I pedal it will not budge. I have had it running, some times very well, though a lot of the time I had to mess with it in one way or another to get it going. Any suggestions would be appreciated.
I am going to call King's tech support, though I have heard they are not very kowledgeable or helpful. Do you have a company/s you like dealing with?
I am going to call King's tech support, though I have heard they are not very kowledgeable or helpful. Do you have a company/s you like dealing with?
"Now no matter how fast I pedal it will not budge."
By this do you mean the rear wheel locks up when you release the clutch lever?
Is there an excess of fuel smell? Is the spark plug wet if you remove and inspect it?
What you're describing almost sounds as if the engine is flooded, cylinder full of fuel causing a hydraulic lock. That's rare and only happens in sever cases of the float valve in the carb allowing fuel to flow into the cylinder.
Does your fuel petcock at the tank work? Do you park the bike with the fuel left on?
Try shutting the fuel/petcock off, removing the spark plug and riding the bike around, pedaling with the clutch engaged for a few minutes. Replace the plug, don't turn the fuel on, and see what happens. Let us know.
Tom
By this do you mean the rear wheel locks up when you release the clutch lever?
Is there an excess of fuel smell? Is the spark plug wet if you remove and inspect it?
What you're describing almost sounds as if the engine is flooded, cylinder full of fuel causing a hydraulic lock. That's rare and only happens in sever cases of the float valve in the carb allowing fuel to flow into the cylinder.
Does your fuel petcock at the tank work? Do you park the bike with the fuel left on?
Try shutting the fuel/petcock off, removing the spark plug and riding the bike around, pedaling with the clutch engaged for a few minutes. Replace the plug, don't turn the fuel on, and see what happens. Let us know.
Tom
2door, yep, the rear wheel locks up. No excess fuel odor. The petcock works and I close it when the bike is not in use. Tomorrow I'll try your idea of riding with the spark plug out and let you know what happens. Big mystery to me. Thanks for your help.
How much rain is on the road where you're at in Oregon?
Just kidding ~
Sounds like 2door has got ya covered, now I'm questioning all the times I left the petcock on!
Just kidding ~
Sounds like 2door has got ya covered, now I'm questioning all the times I left the petcock on!
too much compression, try using two head gaskets! I have a bike with a slanthead and when I first mounted the slanthead , it was doing exactly what your talking about. Locking up the rear wheel! I added another head gasket and works great.
Hey everyone I'm having the same problem with my bike I have spark and everything but it just wont turn over . I replaced the mag the cdi and the spark plug. When I pull the spark plug out,the plug itself is dry and there is an excess smell of fuel. When I park it I turn the fuel off but when I turn it on it seems to flood the carb. Could I not be getting fuel to the cylinder/?if so how would I fix it. If not any suggestions would be appreciated.
You've got quite a different problem than the original topic poster, so it might be best to start a new thread.
Your piston goes up and down when you try to start it, right? It just won't fire. That's an electrical problem. I'd say check your wiring with a continuity tester and isolate the error.
This guys piston won't go up and down 1/6 times when he tries to start it, which is a compression problem. (hoping it's a compression problem).
Though turn over is a term substituted for engine won't fire, it is being used here in a much more literal sense. That's just one of the things that happen when you take a term that's meant for a full on vehicle and apply it here in motorized bikes, where your starting method is via compression start (push start) instead of an electric starter.
This guys piston won't go up and down 1/6 times when he tries to start it, which is a compression problem. (hoping it's a compression problem).
Though turn over is a term substituted for engine won't fire, it is being used here in a much more literal sense. That's just one of the things that happen when you take a term that's meant for a full on vehicle and apply it here in motorized bikes, where your starting method is via compression start (push start) instead of an electric starter.
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Hey,FileStyle, thanks. Did your bike ever start? Though it was sometimes hard to start, the engine was always easy to turn over and I have had it running many times. Then out of the blue it refused to turn over. Could a compression problem develop after the engine had been run sucessfully?
I had the same problem with the slant head even went through 3 sets of clutch pads I even burned out a set of metallic pads I bought off DuctTaped. Just trying to stat the darn thing. I swapped it to the center hole head and it started right up like a champ I may however put the slant back on and try the double gasket seal deal. How can that help I wonder? I know mine was a compression issue because fuel would escape the gasket no matter how tight it torqued it I used the same gasket on the center hole head & had no leaks. The slant heads definitely make way more compression . It destroyed my pull starter first time I pulled it the bike came 1' foot off the ground and the kick stand landed "all bike weight" on top of my foot I pulled a muscle in my forearm it it felt like I ripped of two fingers so there I am hopping up & down like an Indian doing a war dance holding my forearm and looking at my hand I was mad. So mad I took my 32 oz Estwing and ended that pull starters career then and there. I always wanted one of those 49 CC plates anyways 
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