GY6 Rear Tire Locked Up

[RaveningRyan]

I am new to the site although I've been directed here many times from goggle searches. With that said I apologize if didn't search the forum long enough to find a similar thread.

I have a 2009 Chinese GY6 150cc scooter. I bought the scooter off Craigslist and have been troubleshooting problems ever since.

Yesterday I was out for a ride and it was doing fine, however I pulled into the yard and parked the bike and my rear tire locked up. Manually the tire will rotate back and forth about a half inch. If I crank the scooter and apply throttle the tire will turn. I've been searching Google and YouTube for answers only finding results about drum brakes this scooter has disk brakes front and back. I don't know what I need to remove, clean, adjust ect. Any advice would be greatly appreciated.

[blueboy5000]

The first thing you need to do is take off the CVT cover and check out the CVT.

[RaveningRyan]

Okay I've already done that. There is no foreign objects in there, belt is on tight. Manually turning the variator it gets really hard to turn in one spot. Is there any information you can give me to check if it is indeed the variator or clutch causing the problem?

[bandito2]

Originally Posted by RaveningRyan

Okay I've already done that. There is no foreign objects in there, belt is on tight. Manually turning the variator it gets really hard to turn in one spot. Is there any information you can give me to check if it is indeed the variator or clutch causing the problem?

1)
First things first. This has a parking brake? Make sure the parking brake can be engaged and disengaged.

2)
Same for the (hand or foot operated) brake for the rear wheel... be sure it is gripping when applied and releasing when not.

3)
Is it just in one particular spot? Normally when turning the variator by hand you will encounter resistance. Turning it further, does it seem to all of a sudden become extremely easy to turn then becomes difficult to turn again?

4)
Pull the spark plug wire off and remove the spark plug and try turning the variator by hand again. Not so much resistance this time eh? The resistance is from the piston compressing air in the cylinder.(this is normal)

With the spark plug removed, you will not have nearly as much of that resistance. If you still get a lot of resistance after removing the spark plug, then you can check the brakes, clutch and transmission for the problem.

5)
If turning the variator by hand turns the belt and makes the rear wheel turn, or turning the wheel makes the belt and variator turn then the main problem lies in the clutch.

6)
(replace the spark plug & re-attach spark plug wire)

7)
Will it start and run while on the center stand? does the rear wheel turn while you are cranking the starter? (before it actually starts?)

8)
If it starts & runs and the wheel turns while it idles, will it stall if you stop the wheel by applying the brake while it is idling? If yes, then it sounds like the clutch is not releasing and is not pulling back one or more of the "shoes" indicating a broken return spring or something jammed between the clutch bell and one or more of the "shoes".

9)
This also may be confirmed by turning the rear wheel (with the engine off) and seeing that it makes the belt move. (that is not normal)
The belt should not move by turning the rear wheel. Engine off, the clutch should be disengaged and you will only see the clutch bell spin normally when you spin the rear wheel. The drive belt should only turn while the engine is starting/running.

10)
(with engine off) If the belt does not move when turning the wheel, but there is still the issue of resistance, then it could be stuck brakes, warped brake disk, bad bearings or problems with the final drive gears.

Please explain results & observations at each of these steps to help with diagnosing the problem.

[RaveningRyan]

Thanks a lot for the post Bandito2 very helpful. Unfortunately it's gotten dark on me so I'll have to check things tomorrow.