Sugino BB / Crank Conversion - Advice Needed

[paolo]

I'm running a BB conversion with a 68 shell with a 123mm Spindle Cartridge on my 65 Schwinn American Middleweight. Cranks are 80's Sugino Super Maxi's. Everything works well but the non-drive crank arm is only 5mm clear of the kickstand, and not optimized. The drive side is at least 1/2" further away from the rear frame stay. I don't have any additional measurements for the cranks but they are quite narrow.
Can anyone suggest a better solution? I'm thinking a 73mm Shell and 123mm Spindle Cartridge but can anyone weigh in? I'm sure someone has run this combo but I couldn't find much in the search engine.

Many thanks.

 

[Bicycle808]

Switching shells won't help. You'll need to switch spindles. But, just to clarify: the NDS crank isn't clearing the kickstand when you're riding? Or, it's not clearing the kickstand when you're parked with the stand down and back-pedaling? The former would be a problem, but the latter isn't.

Your biggest concern, of course, is chainline. You'll want the line between your chainring and your rear cog to be as close to straight as possible. So long as your NDS crank clears the stays/kickstand while riding, I'd be mostly worried about the chainline.

I hope this helps. I couldn't find what the recommended BB spindle is for the Super Maxi, and beyond that, I don't know what rear hub/cog you're running...

 

[paolo]

Very helpful and thanks for the response. I'm running a 14t rear sprocket / 44t front sprocket Bendix Coaster. The NDS Crank clears the upright kickstand while pedalling but just by a hair, 5mm or so. The DS Crank portrudes about 1/2" more than this but the chainline is good, and the front sprocket clears the frame nicely. Not really a big deal, I just thought there was a more optimal solution, but I am realizing that aside from finding some crazy offset spindle / cartridge, that this might be good enough...

Many thanks

 

[Bicycle808]

Very helpful and thanks for the response. I'm running a 14t rear sprocket / 44t front sprocket Bendix Coaster. The NDS Crank clears the upright kickstand while pedalling but just by a hair, 5mm or so. The DS Crank portrudes about 1/2" more than this but the chainline is good, and the front sprocket clears the frame nicely. Not really a big deal, I just thought there was a more optimal solution, but I am realizing that aside from finding some crazy offset spindle / cartridge, that this might be good enough...

Many thanks

Any time. I'd say that, as of right now, if it ain't broke... =D

 

[user 135]

Try flip flopping the spindle so the drive side is now on the non drive side.

Looks to be a sealed unit. Those can't be reversed.

 

[paolo]

That's a good idea - I should look at non-sealed BB units to see if the spindle can be flipped - worth a try. Thanks again everyone...

 

[user 135]

How about spacing out the adapter on the non-drive side?

 

[paolo]

That, in conjunction with a 73 x 126 might just work.

 

[Bicycle808]

It might help things look "cooler" near the kickstand, but it's kind of a moot point, as kickstands immediately slaughter the "cool" factor. :shock: Of course, if chainline with the 123mm spindle is, in fact, near-perfect, it wouldn't make a lot of sense to use a longer spindle or otherwise offset the BB, just so the 5mm clearance at the kickstand can become 6.5mm of clearance.

 

[Bendix]

Doesnt matter if it is sealed. the spindle still separates from the bearings and cups. If it didn't, you couldnt put it in.

it's a cartridge unit, like this. the spindle doesn't separate.

note the lack of a lockring in the OP's photo.

:wink:

 

[alecw35]

The frames designed for a one piece crank that naturally has the crank arms sitting a fair way from the frame, as it would be difficult to get it thru the BB shell if it had tighter curves.

The alloy crank is probably designed for use on bikes with thin tyres and more or less straight chainstays. So isnt the more modern "low profile" cranks that have a bend along the arm.

I have seen a fair few sealed Bearing units. Some of the Shimano ones have cups that come off both sides. But the other ones seem to be solid mounted to the drive side cup.

How is the sidestand mounted? is it on a welded on boss? If its just bolted on, maybe you could move it about a bit.

 

[paolo]

Great points from all.Thanks again. The chainline is near perfect, and nothing makes contact. And yes, these Sugino cranks are made for way narrower frames. Perhaps that's just the way everybody runs them. It rides fine. What is really needed is a sealed cartridge with an offset spindle. Good luck with that I'd imagine.