Would BBSHD chainline work [temporarily] with vintage 112mm O.L.D hub? 20" wheels

[ttgg]

Hi, I have a late '60s steel-frame department store bike [Sears Tote Cycle] with 20" wheels that I'm thinking of putting a mid-drive on [I already have the BB converter/adapter for one piece cranks]. It's a mini-cargo bike that I really like. Looking at getting Sturmey Archer hubs with internal drum brakes [for reliable year round NE USA riding], probably the 3-speed in the rear and dynamo up front with 90mm brake. This would involve spreading the dropouts.

In the meantime, if I wanted to install a BBSHD first just to mess around with at slow speeds, will the chainline work with my existing rear hub? Trying to visualize it, wondering if the chainline would be angled in too steeply due to the usual rear dropout dimension being 135mm as compared to my 112mm.
thanks for your time and any info!

[paxtana]

Do you mean coaster brakes? Those are not compatible with bbsxx mid drives since backpedaling won't cause it to move the chain backwards, the chainring will freewheel instead, as this is needed for the motor to work correctly.

For chainline it'll probably depend what chainring you are using, and what gear you keep it in if it's using a cassette or screw on freewheel. If you need to lug it in the wrong gear then it'll probably be hard on the drivetrain so that's worth keeping in mind.

[ncmired]

Hi - 112mm? I wonder if it wasn't really supposed to be 110mm nominal. I dunno. Presuming this bike has a 1/8" chain and you tried to run it with the BBSHD and the stock chain ring (and a new chain), I wouldn't be surprised it balks and throws the chain. Do you have a front rim brake? Looks like some of these bikes didn't.

If it were my build, I'd go with the BBS02 - plenty fast enough with more chain line / ring flexibility.

Here's some restoration thread posts for one of these bikes involving a rear triangle spread to 135mm, using an 8-speed back with the drum front:

• https://www.bikeforums.net/17652808-post1.html
• https://www.bikeforums.net/17894485-post41.html

112 to 135 is a big spread - he made new frame bridges to compensate. I think his bike turned out pretty nice:

[ttgg]

Do you mean coaster brakes? Those are not compatible with bbsxx mid drives since backpedaling won't cause it to move the chain backwards, the chainring will freewheel instead, as this is needed for the motor to work correctly.

For chainline it'll probably depend what chainring you are using, and what gear you keep it in if it's using a cassette or screw on freewheel. If you need to lug it in the wrong gear then it'll probably be hard on the drivetrain so that's worth keeping in mind.

Thanks paxtana, The 3 speed IGH Sachs Torpedo has a coaster brake so yes I realize I'd be losing that, I'm talking about just puttering up and down the street at a few mph to get a feel for things before I mod the frame and lace up new hubs [both of which I've never done]. There is just the one gear wheel on the back so trying to visualize if the chain would be at quite an angle with the hub being so narrow.

It might be the stock bbshd chain ring, this is for cargo/slow-ish road use, I read the stock ring can suffice in that domain?

Hey, I see you're an administrator... I subscribed to this thread but didn't get any email notices? Just swung back through today and saw these replies, thanks.

Hi - 112mm? I wonder if it wasn't really supposed to be 110mm nominal. I dunno. Presuming this bike has a 1/8" chain and you tried to run it with the BBSHD and the stock chain ring (and a new chain), I wouldn't be surprised it balks and throws the chain. Do you have a front rim brake? Looks like some of these bikes didn't.

If it were my build, I'd go with the BBS02 - plenty fast enough with more chain line / ring flexibility.

Here's some restoration thread posts for one of these bikes involving a rear triangle spread to 135mm, using an 8-speed back with the drum front:

• https://www.bikeforums.net/17652808-post1.html
• https://www.bikeforums.net/17894485-post41.html

112 to 135 is a big spread - he made new frame bridges to compensate. I think his bike turned out pretty nice:

Heh, thanks ncrkd, when I first found them I went kind of crazy on the Tote Cycle as far as web research and have studied that build thread extensively [it's actually a woman who did it]. Yeah it's a beauty, I'm kind of using that as a blueprint but I'm sure mine will be looking quite funky. As an aside that thread lost all its photos when that big hosting site changed their policy, which was a cruel blow when I went back to it a while back. Then... I revisited a couple months back and Voila! somehow all the photos were back up!

Yeah I have the front rim brake. I just wanted to put the motor in and putt up and down the street before modding anything, I've never even been on an e-bike and was just getting kind of antsy.

Only from reading [I have no experience] I was leaning towards the bbshd because this build is for heavy duty local cargo duties, including pulling a trailer. From what I gather the BBSHD can handle heat or any other problems in that scenario better than the other bbsxx's. And also with a new Sturmey Archer 3 speed igh, I was reading how you can shift less with the BBSHD, it can handle the load better.
thanks

[paxtana]

Yeah emailed notifications should be turned off by default last I checked.
To turn them on go to user settings for your account (click dropdown top right)

[ttgg]

Yeah emailed notifications should be turned off by default last I checked.
To turn them on go to user settings for your account (click dropdown top right)

Thanks, I think someone walked me through this before, when I went to settings email notifications was set to "on daily"... which apparently was not working? Nothing in regular email or spam for this thread. I just changed the settings to "on", which I assume means instant.

On thinking this over, I notice both the replies are marked as "1 day ago", perhaps with my old "on daily" the notification had not been sent yet... does "on" mean more or less immediate?
thanks

[paxtana]

Well I suppose we ought to test that. Did you get emailed when I sent this reply?

[ttgg]

Well I suppose we ought to test that. Did you get emailed when I sent this reply?

Yes, email notice just came in. Looks pretty immediate to me! I'll be curious to see if notices for the other 2 come in later, or maybe they got whacked now that I've changed my setting to "on".
thanks