Back wheel is locked up, Help Please!!!!!

GoldenMotor.com

johnny70

New Member
Aug 12, 2012
6
0
0
chicago
Im new to this and i recently installed a motor kit and im having an issue where I would release the clutch lever and the back wheel would lock up and the engine isnt starting or turning over. I have had the bike for a week and its been starting and running everyday. today though i encountered a problem. I started to pedal down my drive way and as i got enough i released the clutch lever and the engine just froze up and the back wheel was not moving. I then stopped had the clutch lever out to see if i can just try and turn the engine over. nothing the rear tire just gets stuck. I dont know what happened , i think i seized the engine. I dont see the piston moving either. Anyone with suggestions or help please reply i really want to just ride it again. PLEASE HELP!!!!!!!!!!!!!!!!!!!!
 

bigbutterbean

Active Member
Jan 31, 2011
2,417
3
38
Lebanon, PA
Here is one way to check if the engine is seized (sounds like it is, but this test is easy). Remove the spark plug. Then, with the clutch out, place your thumb over the spark plug hole and try to roll the bike. If your thumb gets pushed out of the hole, your engine is ok but something else is wrong. If the wheel locks up again, your engine is seized. It sounds like you either used the wrong kind of oil in your gas, didnt mix it well enough, or didnt use enough oil for your break-in period. the amount of oil to be used for break-in is usually recommended to be double the amount you would normally use. Some people use a little less than that. You may have also been running wide open throttle, causing the rings to get too hot and not seat properly. If the engine is seized, it might still be ok. Take your head off (where the 4 bolts are on top of the engine). take a small piece of wood (I used a toilet plunger handle when I had a seized engine). place it in the cylinder and GENTLY tap a few times with a hammer or something. If the piston comes loose in a few taps, you might be ok. If not, keep hitting harder anyway because you will need a new cylinder. Once the piston is loose, inspect the cylinder for scratches. If you dont see any scratches, you are ok. if you do see scratches, even the smallest scratch, you will need a new cylinder.
 

MotorBicycleRacing

Well-Known Member
Jul 28, 2010
5,844
109
63
SoCal Baby!!!
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Im new to this and i recently installed a motor kit and im having an issue where I would release the clutch lever and the back wheel would lock up and the engine isnt starting or turning over. I have had the bike for a week and its been starting and running everyday. today though i encountered a problem. I started to pedal down my drive way and as i got enough i released the clutch lever and the engine just froze up and the back wheel was not moving. I then stopped had the clutch lever out to see if i can just try and turn the engine over. nothing the rear tire just gets stuck. I dont know what happened , i think i seized the engine. I dont see the piston moving either. Anyone with suggestions or help please reply i really want to just ride it again. PLEASE HELP!!!!!!!!!!!!!!!!!!!!
Sounds like your chain is bunched up under the sprocket cover and jamming your motor.
Undo the 3 screws from the sprocket cover, remove it and see what is going on.
 

bigbutterbean

Active Member
Jan 31, 2011
2,417
3
38
Lebanon, PA
if the chain were binding, he wouldnt be able to move the bike with or without the clutch engaged. he said he can pedal the bike without the clutch engaged. its not the chain. its seized.
 

nightcruiser

New Member
Mar 25, 2011
1,180
2
0
USA
I tried tapping the piston its not budging, i wondering if it has to do with anything with the clutch....
If you remove the small bevel gear, that will disconnect the clutch from the crankshaft and tell you for sure if the problem is in the clutch or the motor. I would guess motor.
 

bigbutterbean

Active Member
Jan 31, 2011
2,417
3
38
Lebanon, PA
the piston aint moving, most likely its seized, and hard too. your cylinder is ruined. you need a new top end, or a new engine if you aren't comfortable installing a piston and cylinder.
 

MotorBicycleRacing

Well-Known Member
Jul 28, 2010
5,844
109
63
SoCal Baby!!!
www.facebook.com
If you remove the small bevel gear, that will disconnect the clutch from the crankshaft and tell you for sure if the problem is in the clutch or the motor. I would guess motor.
You don't need to remove the gear.

Take the magneto cover off on the left side and try turning the
nut with wrench. That will turn the crankshaft and move the piston.
Don't force it if it is stuck.

Do you have the head off?
What else did you do?
Did you take the clutch cover off?

You ain't giving much feedback so you are making it hard to get
advice. :)
Taking a few pics would help solve your problem.
 

johnny70

New Member
Aug 12, 2012
6
0
0
chicago
do i need a whole top end or could i just get a piston and rings, also i looked at the piston and the rings seem to have been broken.
 

johnny70

New Member
Aug 12, 2012
6
0
0
chicago
well as of right noe i have the clutch covers off, top end is off and the piston aint moving, the small bevel gear wont budge and the large one wont budge .
 

johnny70

New Member
Aug 12, 2012
6
0
0
chicago
Ok so i had time to look at my bike further and the piston and the cylinder body are all good but i noticed on there is a crack going horizontally on the crank, could that be the problem?
 

cmanns

New Member
Jul 1, 2012
132
0
0
Santa Cruz, California
If piston cyl body look fine, it wouldn't of been seized from crank.

Doesn't sound like OP's ever had it riding, that sucks it's acting like it's seized if you havn't rode it much.
 
Feb 3, 2018
31
0
6
37
Here is one way to check if the engine is seized (sounds like it is, but this test is easy). Remove the spark plug. Then, with the clutch out, place your thumb over the spark plug hole and try to roll the bike. If your thumb gets pushed out of the hole, your engine is ok but something else is wrong. If the wheel locks up again, your engine is seized. It sounds like you either used the wrong kind of oil in your gas, didnt mix it well enough, or didnt use enough oil for your break-in period. the amount of oil to be used for break-in is usually recommended to be double the amount you would normally use. Some people use a little less than that. You may have also been running wide open throttle, causing the rings to get too hot and not seat properly. If the engine is seized, it might still be ok. Take your head off (where the 4 bolts are on top of the engine). take a small piece of wood (I used a toilet plunger handle when I had a seized engine). place it in the cylinder and GENTLY tap a few times with a hammer or something. If the piston comes loose in a few taps, you might be ok. If not, keep hitting harder anyway because you will need a new cylinder. Once the piston is loose, inspect the cylinder for scratches. If you dont see any scratches, you are ok. if you do see scratches, even the smallest scratch, you will need a new cylinder.
I...... Have the same problem by back tire ia locked up it wont spin with or without the clutch engaged how do I fix that?
 
Feb 3, 2018
31
0
6
37
if the chain were binding, he wouldnt be able to move the bike with or without the clutch engaged. he said he can pedal the bike without the clutch engaged. its not the chain. its seized.
My bike won't move with or without the clutch engaged is it the chain that's jammed up?
 
Feb 3, 2018
31
0
6
37
What tools do I need to take out the three screws I tried taking them out bit one is really in there and it started to strip
 

crassius

Well-Known Member
Sep 30, 2012
4,032
158
63
USA
make sure to take the nut off the one on upper right

if one still will not turn, it is best to use a hand impact driver