Marin Muirwoods + TSDZ2, which chainring?

[skestans]

Hi all,

Very happy with my muirwoods and TSDZ2 along with the open source firmware. Been riding for 7 years now with a 52V battery.

I’m doing a serious service of the bike now, taking everything apart to clean/lubricate, replace worn parts etc.

And so I’m considering replacing the chainring. It’s the stock one with 42T, and with this I could never go past the 6th gear out of 9. It’s just too hard. One of the screws in the spider is seized and corroded and won’t come out so I’ll have to replace the spider anyway. Was thinking of getting a 104 BCD adapter to have a more standard setup and get less teeth on the chainring.

Cassette is 12–36T with 29” wheels. Assist cuts off after 25kph (I used to have it unrestricted to 45–50kph but that was too dangerous and illegal so I put the limit back).

How many teeth do you reckon I should get? What about clearance with the motor’s body and the chain line? I’m a little lost and don’t know how to choose.

Thanks!

 

[E-HP]

Cassette is 12–36T with 29” wheels. Assist cuts off after 25kph (I used to have it unrestricted to 45–50kph but that was too dangerous and illegal so I put the limit back).

How many teeth do you reckon I should get? What about clearance with the motor’s body and the chain line? I’m a little lost and don’t know how to choose.

Thanks!
[/QUOTE]

Which adapter are you planning on using? If you’re going with a smaller chainring, it’s less likely that you’ll have clearance issues, if the adapter has the same offset. Different adapters have different offsets, so selecting the one that gives you the best chainline is the main concern.

 

[skestans]

I don’t know which adapter I’m getting. The offset is how dished in it is inwards/towards the frame? How offset is stock, 2mm?