Ebike - Chain problem

Hey fellow ebikers

I am doing my first build at the momemt, but have encountered kind of a problem.
I have a freewheel (single gear) on my mxus v3 motor on a 17' moto rim with a 2.5' enduro tire on.
The chain is close to the tire after I put the chain and the chain tentioner on. The chain is about 6-10mm from the closest point of the tire. I am afraid if it will get into the wheel and the spokes.

What do you think? Have you tried anything similar or do you think I will be okay?



- Mpmoller

That should be just fine. Even when the chain slaps into the tire, its getting pulled down, so no danger of getting sucked up between the tire and chainstay. For better control you could add a lower chain guide at the bottom bracket.

*EDIT
Although, I'm still in a pedal bike mindset, assuming that the top of the chain will always be tensioned by pedalling. I still don't think it will be an issue though.

Epyon said:

That should be just fine. Even when the chain slaps into the tire, its getting pulled down, so no danger of getting sucked up between the tire and chainstay. For better control you could add a lower chain guide at the bottom bracket.

*EDIT
Although, I'm still in a pedal bike mindset, assuming that the top of the chain will always be tensioned by pedalling. I still don't think it will be an issue though.

Click to expand...

It's not a bad idea to add a chain guide. Do you have a bike with a smilar setup like me? You know, the chain is close to the wheel?

mpmoller said:

It's not a bad idea to add a chain guide. Do you have a bike with a smilar setup like me? You know, the chain is close to the wheel?

Click to expand...

I use to race downhill in the early 2000's. I've always tried to run the largest tires that would fit, so yeah many of my bikes have had similar clearances. Of my current rides my Specialized Demo has the tightest clearance. About 4mm in the lowest gear in a 1x10 setup with 3" tires (WTB Rangers).

Epyon said:

mpmoller said:

It's not a bad idea to add a chain guide. Do you have a bike with a smilar setup like me? You know, the chain is close to the wheel?

Click to expand...

I use to race downhill in the early 2000's. I've always tried to run the largest tires that would fit, so yeah many of my bikes have had similar clearances. Of my current rides my Specialized Demo has the tightest clearance. About 4mm in the lowest gear in a 1x10 setup with 3" tires (WTB Rangers).

Click to expand...

What kind of chain guide do you use?

mpmoller said:

What kind of chain guide do you use?

Click to expand...

On the Demo specifically, an older Ethirteen TRS (IIRC). I've used many different ones. Just about all do the job well. Going waaay back, the old MRP guides with hard rubber rollers, I never liked. Does your frame have ISCG mounts? If so, be aware there are 2 standards, ISCG (usually referred to as ISCG-old) and ISCG 05 (newer standard, larger bolt circle diameter). If you have just a plain threaded BB, you can either get a guide made specifically for that or get an adapter to run either ISCG. I'll also mention that chain guides, for some reason, are stupidly expensive for what they are. Look for a used one.

If you have enough threads on the hub you can also add spacers between the hub and freewheel to have it stick out farther. And/or add spacers to the pedal chainring to make it farther out from the frame.

Disadvantage to both of these is taht if you actually are cranking hard it puts more stress on the bearings, hub cover, etc.

But with that motor I don't expect you'll be doing a lot of hard pedalling.

Thanks guys!