Recent content by bengxe

Only on the internet. That frame is probably straight gauge 4130. I'm guessing this is already a heavy bike, I wouldn't want to add any unnecessary weight. I can't tell from the pictures, is your idler bracket attached to/ part of the motor mount plate somehow? If not, it probably should be...

Do you have the chain to tire clearance to offset your rear sprocket towards the spokes a bit instead of adding an idler?

Close, but no. MY1020 uses a 8x10mm shaft, that's for a 8x12 shaft.

Front sprockets are the problem with 219 chain and the my1020. They don't exist, so 219 is only useful as a second stage. I agree 219 would be nice, but it doesn't have huge advantages over #35. My first attempted e-bike project was a my1020 on my downhill bike. I ran into so many problems...

There's also more stability in a longer wheelbase, and the fork manufacturer that you linked seems to say that that's more beneficial for high speed handling. Edit: A 26" suspension fork would raise the front end significantly, there's no need to go for the wrong wheel size. 29er forks tend to...

A 20" fork? But it looks like that company does recommend the largest offset/ smallest trail for "high speed trails". If OP wants to spend that kind of money they could have front suspension and a disc brake. That'd be a worthwhile increase in trail.

I see no indication that is meant for a bafang lock nut, or anything about the size of the parts that matter. It might work, it might not. I use a hammer and screwdriver for this.

I don't have any experience with KT specifically, but have you measured the amp draw of the new and old controllers? 28 and 30 are close enough that your 28a controller may have been drawing more than your 30a KT. Does the sticker on your KT not say 30A +-2A? Your old controller probably said...

You plugged 3x 3s batteries (9s) into a charger meant for 10s. It sounds like the BMSs might be working properly, since you didn't mention a fire.

https://www.mbr.co.uk/news/fork-offset-head-angle-trail-342679 I've tried similar things on full suspension MTBs that have wheelbase to spare, I wouldn't even consider it on a bike like yours. You'd lose wheelbase and shift your weight forward, neither of which are ideal.

Can be but shouldn't be. In this case I suspect if it were fully charged the total resistance would match the manufacturers spec for just the cells. Since these voltage readings come from the BMS there shouldn't be much wiring to compensate for.

The math is pretty simple. You're a little over the spec for the cells at ~9mOhms, they claim <8. I couldn't tell you if this is a problem. Edit: I missed that you had already ridden it 28 miles, I would re-do this test with a fully charged battery...

The only reason this might be true is if the controller has a non-programmable low voltage cutoff.

Another option you have is just rewiring your batteries to parallel the 4 36v packs to halve the motor speed. You should still be able to hit 2500ish watts with your 66amp controller. You could go to a bigger motor sprocket and then maybe still have to go smaller on the rear.

I've seen adapters to put u-brakes like you have in the rear in place of the side pull you'd have to use on that fork. That seems like it'd be an improvement. #35 sprockets exist up to at least 85t, if you can tolerate the noise and chain wear from the 9t you might be able to make your single...