Hello from AZ

That single speed crank says it has a 45mm chain line, but I'm pretty sure that depends on the length of the bottom bracket.

The common bicycle BB size is usually 68mm, but an ebike is usually between 100mm and 120mm long.

That effects the offset from the center of the seatpost to the chainring.
 
That single speed crank says it has a 45mm chain line, but I'm pretty sure that depends on the length of the bottom bracket.

The common bicycle BB size is usually 68mm, but an ebike is usually between 100mm and 120mm long.

That effects the offset from the center of the seatpost to the chainring.
Yep, which is why I don't want to buy a crankset that doesn't carry about a 65 chainline. The mathing here throws me a bit, since the BB number would need to be reduced by half, but there's more to it, yes?
 
A standard BB fits a 68 to 73 frame shell. The difference between then in the length of the square taper shaft. A triple ring takes a longer shaft and you would want to balance that with the Q on the left. The shown ring should work fine. And should be the same distance from the center of the bike as the existing ring, because of the shaft length and taper.
 
Yep, which is why I don't want to buy a crankset that doesn't carry about a 65 chainline. The mathing here throws me a bit, since the BB number would need to be reduced by half, but there's more to it, yes?

Just measure the frame shell and buy a BB with the same measurement.


The shown ring should work fine.

A triple ring takes a longer shaft and you would want to balance that with the Q on the left.

The ring shown isn't really a triple ring.

It's a single chainring with a chain gaurd on either side of it.

It may have a bit more offset than a standard chainring, but not as much as a triple chainring.
 
Just measure the frame shell and buy a BB with the same measurement.






The ring shown isn't really a triple ring.

It's a single chainring with a chain gaurd on either side of it.

It may have a bit more offset than a standard chainring, but not as much as a triple chainring.
I meant that for reasons such as the Q-factor and number of chainrings bottom brackets' shaft lengths differ. I see no reason that ring will not work with his bike. 51-t is large so it will take a longer chain and the stays are long so maybe 129 links. Chains are not sold that long so two will need to be linked. Tell him what you did to your chain.
 
,.. I recall it is something like 38-t, but check to be sure. A larger one is faster, a smaller gives easier climbing.

This is from the Apias website,..


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@Go-Rilla
If you buy a crank set with a 48t chain wheel and 170mm crank arms, it will be a direct replacement, so no chain issues.

I did find standard KMC chains that are 118 links, but for anything longer I needed to buy the KMC Ebike chain which was long enough for my ebike.

You have a hub drive, so you don't really need a high-end crank system.
It's only your rider input going through the chain and sprockets.


You'll probably be ghost pedaling at anywhere near top speed though, so a bigger chainwheel will help you keep up.
 
Tell him what you did to your chain.

I spent 5 hours cleaning, cooking, and waxing one of my new e8 chains ,..

That was July 5th.

That chain is still hanging in my kitchen window. 😁





I have been using my original chain while I figure out how long it needs to be.

I'm going to go with the original length to be able to use both chainrings and all of my gears, except 1st gear on my 52t chainwheel.
 
This is from the Apias website,..


View attachment 214530




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@Go-Rilla
If you buy a crank set with a 48t chain wheel and 170mm crank arms, it will be a direct replacement, so no chain issues.

I did find standard KMC chains that are 118 links, but for anything longer I needed to buy the KMC Ebike chain which was long enough for my ebike.

You have a hub drive, so you don't really need a high-end crank system.
It's only your rider input going through the chain and sprockets.


You'll probably be ghost pedaling at anywhere near top speed though, so a bigger chainwheel will help you keep up.
That is why I selected the 52t over the stock 48. As for high end cranks, I don't consider the ones I'm looking at to be high end, but a needed improvement over the stock cast iron ones.
 
That is why I selected the 52t over the stock 48. As for high end cranks, I don't consider the ones I'm looking at to be high end, but a needed improvement over the stock cast iron ones.


The longest chain I could find was 118 links, so you'd have to join two chains together to get to 122 links.

The KMC e8 chain is specifically for Ebikes, and is 136 links long, so you'd only need a single chain.
(It comes with a quick-link in the package. You'd just have to remove a few links.)


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As far as I know, the 6, 7, and 8 speed chains are the same, but once you get up to a 9-speed chain, the chain starts getting thinner.



The "regular" KMC bicycle chains are about half the price, but you'd need two of them and two quick links (they don't all come with a quick-link), so it's pretty much the same price anyway.
 
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These chains are very nice for the price. Strong and highly polished. Because it is a hub drive it does not really need an eChain. I like to cut two chains to about equal length so I never have two quick links on the pedal pressure top at once.

Zonkie X 8.
 
The longest chain I could find was 118 links, so you'd have to join two chains together to get to 122 links.

The KMC e8 chain is specifically for Ebikes, and is 136 links long, so you'd only need a single chain.
(It comes with a quick-link in the package. You'd just have to remove a few links.)


View attachment 214571



As far as I know, the 6, 7, and 8 speed chains are the same, but once you get up to a 9-speed chain, the chain starts getting thinner.



The "regular" KMC bicycle chains are about half the price, but you'd need two of them and two quick links (they don't all come with a quick-link), so it's pretty much the same price anyway.
There are plenty of fakes on these Chinese marketplaces. Do you know how to tell the difference? You should.
 
On a mid I will use an e10, or e11, e12.

I've got a 7-speed Drift Maniac DNP freewheel, connected to my BBS02B mid-drive motor.

Would you use an e10, e11, or e12 with that ?

Is there any advantages to Not using an e8 chain?
I thought it'd be stronger, last longer, and be able to better deal with a non-perfect chain line?
 
I've got a 7-speed Drift Maniac DNP freewheel, connected to my BBS02B mid-drive motor.

Would you use an e10, e11, or e12 with that ?

Is there any advantages to Not using an e8 chain?
I thought it'd be stronger, last longer, and be able to better deal with a non-perfect chain line?
An e-chain makes sense on a mid-drive. Especially after boiling it in wax.
 
An e-chain makes sense on a mid-drive. Especially after boiling it in wax.


I'm asking if you do, or if you even can put an e10, e11, or e12 on a 7-speed freewheel?


I wasn't gunna bother with an ebike chain, and already had a KMC Z chain in my shopping cart when I realized it was too short, so I bought the e8 chain.

Both my ebikes (hub drives) came with a custom length KMC Z chain.
That's what I've been using while I figure out how long of a chain I need.


.
 

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If you buy a crank set with a 48t chain wheel and 170mm crank arms, it will be a direct replacement, so no chain issues.

@Go-Rilla don't forget about your crank arm offset.

My mid-drive came with crank arms with almost no offset. (because the mid-drive has a longer crank shaft)

The original crank arms needed to be offset to clear the chainstay with the shorter original bottom bracket.
 

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I'm asking if you do, or if you even can put an e10, e11, or e12 on a 7-speed freewheel?


I wasn't gunna bother with an ebike chain, and already had a KMC Z chain in my shopping cart when I realized it was too short, so I bought the e8 chain.

Both my ebikes (hub drives) came with a custom length KMC Z chain.
That's what I've been using while I figure out how long of a chain I need.


.
Using a chain breaker you can easily add links to a chain although that would mean buying a donor chain (which could be used for future chain lengthening of same chain type). I often just use a chainbreaker to connect chain ends instead of quick links.
 
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