Back Wheel Locking

Mopedamauter79 · #1 08-04-2008, 09:06 PM

I have the motor finally installed on a new Bike frame and I release the clutch so I can pedal the bike and it moves 3-4feet forward and the back wheel locks up. I push it backwards while the wheel is locked from going forward and it moves...

I don't understand why it can move backwards but not forward. I'm so not mechanically inclined for these kinda things..But there so fun to drive at the same time..

stude13 · #2 08-04-2008, 10:04 PM

more info please-is the chain binding-does it happen when clutch handle is pulled?

Can Harm Hen · #3 08-05-2008, 02:38 AM

Wow, that doesn't sound normal... mine locks up in both directions when I release the clutch.

Mopedamauter79 · #4 08-05-2008, 03:52 AM

Yes when the clutch handle is pressed in. Normally I would be able to pedal with it in what I call Bike mode.

graucho · #5 08-05-2008, 06:16 AM

Yes, when you are peddaling the chain is spinning (even though the clutch is in neutral) and the chain is bunching up at the small sproket. (under the cover) This has happened to me twice. Maybe im wrong, but its worth a peek. :grin:

Or, one of my old posts... What I did was... took off all covers and took a peek. Everything seemed in place> the little rod and ball bearing was there. So... I took out the spark plug (to reduce compression and allow tire not to be locked up) put in 2 drops of oil for lubrication, went out for a 1/2 block ride with the clutch stuck on. YEA! since this was a brand new install something must have been hung=up from thick grease or a tranny part was'nt seated. But taking it out for a peddal (without starting it) must have moved everything into place. Thanks again. Graucho

jburr36 · #6 08-05-2008, 01:02 PM

I had this problem when I first completed my build. I nearly broke my ankle with the full force of my weight on the down stroke on the pedal when the wheel locked up. I ended up falling over onto the ground rolling in the pain from a badly spained ankle.

Anyway, I came up with a solution that involved some work. I took a couple of pieces of 1/2" X 1/8" bar steel and formed a somehwat rounded chain guide around the small sprocket. I used JB Weld to glue the steel into place. This solution doesn't allow the chain to jump off the sprocket.

I suspect the reason I had this issue in the first place is because of the rear suspension on my bike.

See attached pics for clarity.

James.

Mopedamauter79 · #7 08-06-2008, 06:27 PM

Turns out it was the master chain link that was stopping it from moving as there was a extra piece on it that made that link thicker then it should of been. I had not noticed this at all till my gf figured it out and pointed this out to me..

So it does run however I have the following problems.

The accelerator handle grip has NO effect on the bike acerbating at all. I tried adjusting the idler but it has no effect..

I have noticed the clutch cable keeps slipping and that the plastic is going through that thing that guides it to the clutch arm and is on the other side of the card.

Could the problem of not being able to control how slow or fast it goes without using the brakes to slow it down be related to the clutch not being tight enough.

Finally the JB weld did NOT hold. The engine heated it up and made it very soft and you can peel it off with your fingers..

Suggestions ?

jburr36 · #8 08-06-2008, 07:23 PM

So far the JB weld is holding. I've had the carb loosen up on me but I think it was a combination of the vibration and the bike fell over onto the air filter. I reattached it to the intake manifold with a screw and a lot more JB Weld.

As far as the acceleration I've read a post on another board where someone had the same problem. He can start his engine but it could never accelerate and lacked power no matter how much he opened the throttle. It turned out to be an extra piece of metal that flashed by the mold during casting of the intake manifold. It was like he always had a choke on. He knocked it out of the intake manifold and all was well.

As far as the clutch cable slipping...there should be a metal cap on the end of the cable sheath with a hole in the end for the cable to come out. If it's not there I would find one at a bike shop or somewhere. I trashed that cheap clutch handle that came with the kit and bought a locking clutch lever from a dealer. So much better and safer to drive with that.

Also, if you have an air leak through your carb and intake manifold or the manifold and engine through the gasket the engine will run at high rpms or run irratic no matter the acceleration or idle screw adjustment. Leaky intake gaskets will cause the motor to run hot and could burn it up.

James