Clutch plate bearings

[weefek]

Hello there homie, my 2 stroke project walked the plank, a 49cc 4 stroke engine took its place. The clutch removal threads stripped and it was stuck on, plus the conrod had an excessive amount of play, if I would have been able to get it running, it wouldn't have lasted very long.

So you never got around to doing the 1/8" ball bearing upgrade?

Sucks man.

 

[Otto Neumann]

So you never got around to doing the 1/8" ball bearing upgrade?

Sucks man.

Yeah, I'm done with 2 stroke engines which aren't Hirth branded

 

[weefek]

Yeah, I'm done with 2 strokes engine which aren't Hirth branded

I'm sorry to hear that.

As for the main topic of the thread.

For any Grubee GT5B/A runners out there, the 1/8" ball bearings are NOT a direct replacement. I've had to do a ridiculous amount of sanding to get this thing back together. I don't know what's different between these clutches and everyone else's (maybe it's just the one I ended up with? Who knows) but they wouldn't even slip into the clutch basket at all at first.

The center hole on the clutch basket was out of round (58.10 vs 58.30) to start with, and I'm at around 58.38 all the way around and it's still a little too tight. I could probably run it but I'm worried it will overheat and destroy itself. I'd rather have excess tolerance than it being too tight.

Anything must be better than the literal ~>2mm of slop from the factory.

I've made up a chuck for my drill with a crappy broken clutch shaft to mount the parts on to sand so I don't have to do it by hand. I'll upload pictures / better description when I'm finished. Hopefully this clutch will last many motors like OP (or someone else in this thread forgive me I forget who it was at the moment).

 

[weefek]

Installed the rebuilt clutch on my bike today and did about 8 mile ride with it. The bike is a lot quieter in general, so I know most of the weird noises I've heard since I built the damn thing were due to the crappy stock clutch bearings. I don't know what the factory was thinking or doing but there's SO much slop in the stock clutch it's ridiculous.

I still have a weird metal on metal noise at full throttle full out that sounds much like a loose exhaust heatshield (I'm from the automotive world). Doesn't sound like pinging but it may be. Going to try some 91 gas on the next tank.