Sudden loss of power

[kymco-thundah]

Hello
TL;DR: Lost some power after really straining the engine for a second, any ideas why?
I had attached a pretty tough dog leash to the luggage rack on my Agility 50, to serve as a fastener for my backpack. Somehow the other day, at the worst possible moment (a three second traffic light that leads straight to the highway, 20 cars behind me), it wriggled itself out and even though both ends were still tied, a segment of it got stuck in the wheel. To my great surprise afterwards, the good ole GY6 snapped it, but was put under a lot of stress and I can safely say there's been some power lost somewhere (takes me 10-15s to reach 45kmh/28mph, engine warm and on level ground). Have any of you been in a similar situation? It wasn't no joke, the thing must have exerted a force of at least 90kg/200 lb. The only thing I can think of is the belt having been displaced, but there might be a more technical reason so I'd rather ask. Thanks for any advice

[Redk]

Question:

And this is now noticeably slower acceleration for a 50cc scooter ?
redk

[kymco-thundah]

Question:

And this is now noticeably slower acceleration for a 50cc scooter ?
redk

Trust me, I've driven it for months and now it's been a week. I can tell.

[Redk]

i trust you implicitly under these circumstances !

If a wire-spoked wheel, determine if it is still running true and all spokes are properly tight/not bent.
A wobble, shimmy, or OoB robs HP...

It's possible that a slam-stop of the rotating engine, (like a prop-strike in an aircraft) could do almost any sort of damage to the balanced rotating mass within the engine, including mis-alignment of the crank halves or causing a cam chain to jump a tooth.

A sharp or jarring impact could release a previously settled bit of debris in the fuel system, creating a partial blockage.

...You might also try a different gas station for your next load of fuel...
redk

...this could go on forever !   a serious jolt such as stop-action of the drive wheel, at speed, could have loosened or now be causing an intermittent problem with a vacuum line or electrical connector.  There could have been injury to the air cleaner allowing a clump of debris into the carb or fouling the plug a bit...

Everything can be very critical in a 50cc engine when top performance is demanded.
.