I know, real boat anchors.

I have a 70 something Schwinn Super Sport. Not for the weight weenies. But it sure rides nice. The previous owner installed a single ring cotterless crank with the BB converter doohickie.

So, looking at Super Sports from the 60's I see a couple different chainring designs were used for the Ashtabula cranks. And they look much better than the 70's double chainring with chainguard monstrosity that was standard on my Super Sport. Thinking of converting back to Ashtabula with a nice chainring design. The 5 pin "Sprint" model looks particularly nice. With the big diameter BB I would think the bearings would be smooth runners. And the ease of maintenance is certainly a plus. What think ye?

OK by me.

The Sprint double plateau crankset was used from '64 through '67 and not only looks good, it has 39-50T rings vs. the 39-52T rings on the '68 and up crankset. A chainguard was standard on these only in '67 but it can easily be removed. This one is from '65 thus w/o guard:



Same crank in '67 w/guard:

Thats what I am thinking of. And before these were the 3 pin spiders with Huret 47/50 or some such. But I think I like the 5 pin Sprint look.

.
...when I converted mine, I had to do a little grinding in the BB shell to open it up enough for the conversion unit to fit where the cups came out. Mostly at the weld in the shell, which did not appear to be cast, rather formed and welded. I'm not 100% certain that the cups I took out with the Ashtabula crank would now fit tightly enough in the shell to convert it back, but it's possible they would.

All you can do is try, really, and see if it works.

Yeah, what he said.
Nice looking crank in the mid 60's!
I like the earlier ones too, but that big 2nd ring won't help any climbs.
Here's an aftermarket triple that might not look bad without the guard. Wouldn't it be sweet if the bolt holes were the same as on that Sprint?

I always thought it'd be cool if someone brought out a Ti one-piece crank. But yeah I think your idea is fine, OP. If I had a bike with one-piece cranks I'd prolly just keep 'em, rather than going the adaptor and crank swap route.

...I did it a long time ago, but IIRC part of the issue was pedal availability. I think maybe the one piece cranks on these won't take a 9/16 pedal spindle. (But I won't swear to it. ) There are probably better 1/2" pedals around now.

Yeah I didnt think of that, could be an issue alright.

1/2" clipless pedals were produced briefly, roughly 20 years ago, during an "overlap" phase in the BMX world where 1-piece cranks were still used by some fairly serious BMX riders.
Clipless pedals arrived just as the 1-piece cranks were being phased out on mid-level and better bikes, so production of the pedals ended almost as soon as it had started.
I've located a few pair of the Wellgo-made, double-sided "Clipless BMX" pedals for use on spirited rides on my Varsity and Supersport bikes over the years, they still turn up but are increasingly rare today. I look for these pedals mis-represented as regular MTB pedals and often as not find them sold under the Bulletproof brand.

Yeah, me too. An Ashtabula crank in Ti would be insanely cool. Would not be easy to fabricate, but it's doable I think. Probably wouldn't make any sense financially, which just makes it cooler. The entire market for such a component would be about 3 people...

Not Ti, but werent there actually some high-end 1 piece cranks made BITD? I vaguely remember there being some pretty slick cranksets during the BMX craze.

Those pedals posted above are really cool btw, never seen those before.

I kind of like the original Varsinental cranks with the Simplex 3-to-6-bolt adapter set. They could take standard steel or aluminum European chainrings such as these:

Ashtabula cranks are indeed very easy to maintain.

I absolutely love the SR tubular cr-mo cranks I installed on my Dahon. They are light, smooth and I love the way they look:

Wow! Did those original on your dahon? Never seen those before.
Also, how do you like the folding bike? Good for commuting, or...?

Now this is getting interesting. I didnt know about these. Looked at a few on ebay. Very interesting and in 175 length as well. I like this crank a lot.

The monstrosity shifts great, fwiw, having a ramp pressed into the big ring; and the bash guard covers the FD completely, no danger to shoelaces. That and the turkey levers and stem shifters make it a bike to ride with zero preparation, ideal for commuting. I’d have kept mine but I convinced myself I wanted less weight, indexing, and braze-ons.

Yeah those are sweet. Like I posted, I do remember there being some pretty nice 1 piece set-ups back in the 80's. Pretty cool.

Wow indeed. Those SR tubular cr-mo cranks ^^^ are really interesting. I had no idea they existed. Look perfect for a utility bike like the Dahon. Can you buy them or is it an OEM only thing? I'm going to have to look into those.

For a while now, I've been waiting for someone to make a racing cr-mo hollow crank, like the old Bullseyes. Press fit BBs and master links trickled into road bikes, why not those too... In fact there are some bullseye type cranks in Ti made in Germany or something.

exmechanic89 - Yeah I remember some fancier ashtabula type bmx cranks. Mostly they were just polished a bit more. Some were cr-mo though. It might be pointed out that the modern 2 piece hollow road crank was originally developed for BMX.

I bought the SR tubulars on eBay, and they significantly lightened the bike. The SR cranks are 660 grams, which sounds like a lot until you realize it includes spindle and crank bolts effectively.