Rear wheel roll resistance when been driving. Not when cold.

[bendover]

Bike is Aprila SR 125 (Piaggio AC 125cc 2 stroke). Rear drum brake.

Rear wheel has high rolling resistance when I've been driving. After cool down (5 min or so) it rotates freely. The resistance is uneven when rolling, it's in a specific spot along the turning of the wheel. I notice no wobbling. Rear brakes (drum) work fine. Recently had rear tire changed - new bike, haven't been riding before, so not sure it was before that. I suspect this bike have been crashed somewhat by previous owner (new fairings, front brake handle bent, a minor sheet metal piece was bent inside underbelly fairing left hand side).

Any clues?

[190mech]

Sounds like a clutch shoe has a broken spring causing drag...

[bendover]

Oct 21, 2017 14:05:59 GMT -5 190mech said:

Sounds like a clutch shoe has a broken spring causing drag...

Thanks for feedback! Thought: I can't get my head around it though, wouldn't that give an equal resistance the whole revolution of the wheel? If I roll with hand, the clutch wouldn't engage due to too low speed? And why does it only drag when hot? I might be too stupid to understand!

[190mech]

Stuff heats up and expands,thus drag when hot!

[honda4life]

Yeah unlikely the rear end sustained the damage if the front stuff was replaced.
It's the drum brake dragging...more than likely.
Pull the rear wheel and see if it is dragging.

[90GTVert]

I've had this with the drum brakes on my Chinese scoots. The darn things are out of round way too often. Sometimes they have to be backed way off on the adjuster to avoid contact, then you have hardly any braking in the rear. If they do rub at all, they'll heat up and it will get worse.

Can also be the clutch as 190 said. Bell not concentric, something causing a shoe to sit out a little more, maybe one spring suffering from heat fatigue worse than the others.

You could try backing off the brake adjuster when it's doing this. If it suddenly rolls fine, then you know you need to check the brakes.