m@Robertson
Well-known member
Ugh. If I had known what chain you were using I'd have pointed right at it.It’s a Zonkie 1/2x3/32 chain and a shimano Alivio cassette. Shimano derailleur, but don’t recall the model off hand. It’s a new one and adjusts correctly, shifts smoothly, as far as I can tell. Have a 32 tooth aftermkt front drive aluminum sprocket, but it does the same with the bafang 44t steel one too.
I’m wondering if a high end chain might help? Are there some that operate more smoothly? Even changed the shifter.
Your chain is 6, 7 and 8s compatible. Zonkie (which I have never heard of) does not publish their outer chain width other than to use the sort of generic standard of 3/32". 3/32 of an inch works out to 0.28125", which translates to a metric value of 7.14 millimeters. Why do we care?
Remember that chain is supposed to be 6/7/8s compatible. Well, 6 speed chain standard width is 7.8mm. 7 speed is 7.3mm and 8 speed is usually between 7.0 and 7.3mm. So, IF their sizing is to be believed, your chain is a touch on the narrow side. It still should be compatible, but since you are experiencing problems I would say its a prime candidate for replacement.
A KMC Z7 is 7.3mm wide. US$13 on Amazon. Go for that one. It still may not be your problem. Unfortunately an Alivio cluster is bottom of the line. Its about a $16 part. But thats what you have to take when you are on 7 speed. Same with the chain. Its not mid drive stressed but KMC is the value-priced durability standard in the DIY industry, so its as good as you will get for 7s.
If I had an opportunity to advise in advance of this build, I'd recommend a Microshift Advent drivetrain. 11-46T Steel cluster is durable for a mid drive (your Alivio is too) and only $39 for a quality product. The derailleur and shifter are matched to it and only run about $100 for the pair. And its 9s which means you have a slew of quality mid-drive-strong chain options in addition to having more gears to choose from, which riding overland like you do, you would benefit from. 9s is the value/budget standard for hi powered DIY mid drives.
Maybe take a look at this:
How To Build a Mid Drive Ebike That Doesn’t Break
Mid drives up the ante on the required competence of the builder. Read this so your bike lasts without things breaking or wearing out early.
talesontwowheels.com
I thought you said you already had good alignment? If you don't, then thats a problem too. A skewed chain under power will always make Bad Things happen.Maybe one of those dished sprockets for a little better alignment?