Changing Crankset
 

First of all I'd like to say that I have a Pedelec Foldable Bike, from Longwise, a company probably nobody heard of. The type of company that helps you buy their items and abandons you when you ask for parts and assistance. They refuse to answer my emails.

Anyway, I had the bike for over a year now.
I was riding it when all of a sudden the right pedal started to wobble, I had no idea what was wrong but I managed to get home and noticed that the crank thread was completely gone! I read online that probably the pedal wasn't fitted well.

I bought a crank puller and took the crank out, it is a Lanhang-52T-170L-quite heavy.
I went to 3 bike shops but I didn't find anything like it, they were either smaller or had more than one gear.... *phew!* I was also told that the thread couldn't be replaced/fixed.

I checked online and I found the following cranks which should be exactly or close to the one I have, what are you thoughts on these?

- TMC Single Speed Fixie Bicycle Fixed Gear Bike Crankset Cranks 52T | eBay

- MTB Crankset Crank Chain Wheel BCD130 Square Hole 52T Chainwheel with Shield | eBay

- Lasco Bicycle Crankset 52T 165mm Bike Chainwheel Alloy Chainring Chain Guard | eBay (slightly shorter)

Sorry for the long text, I would really appreciate some assistance as I have nobody that's experienced to help me. Thanks!

No experience with your choice of parts .. All I can offer is.. If you screwed up the frame's threads ,

a Professional Bike Shop that has the BB treading tools, May, be willing to fix them, for their Fee. (Ask them what it is)

often cited is the Velo Orange sold BB made to not need to use the Threaded BB shell
Grand Cru Threadless Bottom Bracket

You can look for a helicoil repair kit for the pedal thread, but a cheap crank might be less expensive. One or two teeth difference will be barely noticable

Sounds like its a chinese electronic folding bike with a single speed type crank? Maybe search for the crankset name and try to buy something similar online. Is this close to it?

Aliexpress.com : Buy Lanhang, Single Speed Fixed Gear Crankset, 46T 170mm BCD 130mm.Retro Bike, Track Bike Racing Crankset, CP style. from Reliable gears of war series 2 suppliers on Sherlock's Fixed Gear and Bike Bicycle World | Alibaba Group

Worse case, you should be able to replace the crankset with another brand as long as the chainline is similar. Would also have to replace the bottom bracket, but that shouldn't cost much more.

Thanks for all the replies.
Yes its a single speed crank (with 6 gears being on the side of the back tire if that makes any sense) wouldn't the ones I found on ebay match? Fixie is the same as single speed right?

Try the Bicycle Mechanics forum. A moderator should move this.

Yes. Measure your bottom bracket spindle length. Then try to get one with a similar length if you're going to replace it as well.

"A fixie is the same as single-speed, right?" Not quite, though the difference is probably not relevant to your situation. A fixie has a "fixed" hub in the rear wheel... no coasting, the wheel and crank always turn together. A single-speed bike has a freewheel mechanism built into the rear hub so you can coast. Hope that helps.

with a 6 speed cluster the 1 chain ring should be in a straight line with the gap between 3rd and 4th cog of 6 Ie, the center..

Ideal chainline. [ odd number 'speeds' there is 1 cog in the center .. 5, 7, 9...]

I ordered two cranks off aliexpress, one from "electric bike house" was for a bmx 152mm new crank. I got a poorly wrapped, scratch/used (pedals mounted) 170mm really ugly crank, and also another vendor for a Lasco 165mm 46T crank. I did receive the lasco, shipped well, but 40 days later, 170 mm (instead of the 165 ordered) and 48T (not the 46T) I ordered. Not worth the headache. I'm disputing the order with "electric bike house", and going through the dispute process, they lie like a rug. YMMV.