niliraga 

Here's my conundrum - I'm hoping to repurpose an old Cilo roadframe for use on rail trails and the like, making some good use of its wide tire clearances. It has the original Campy NR bracket in there, with french/swiss threading - not sure which as i've not been able to remove fixed cup in either direction, so have let it be.

My idea is to find and use some the 110BCD cranks I have handy -- but Sugino VP and GT cranks are bottoming out instantly against root of the tapers, of course - no surprises here so far. However, I do notice that some non-Campy cranks appear to sit fine on these tapers -- eg. my spare Super Mighty seems very happy on the Campy spindle, but of course 144BCD doesnt give me anything that the original NR cranks cant.

I could probably find a NR-compatible spindle with different tapers and rebuild the BB around that, etc etc., but this is just a fun experiment so I'm hoping to do this on the cheap with a local/co-op cheapo crankset rather than make it a full-throttle, spare-no-expense eBay project.

There are many threads about fitting NR cranks onto different/modern BBs, but precious little info going the other way - has anyone got any wisdom to share on this, anecdotal or otherwise?

nomadmax 

Here's a good link regarding JIS and ISO crank/BB tapers.

https://www.sheldonbrown.com/bbtaper.html

That said, when I was an indigent bicycle racer I put JIS cranks on ISO (Campy) BB spindles by cutting small rectangular pieces of beer cans (Coors of course) and used them as shims on all four sides of the BB spindle. If you played with the length of the shims (held in place during install with grease between the shim & BB spindle) you could adjust the chain line. I also used this trick on worn Campy cranks that would draw down onto the spindle too far. Now days if i were going to do it again (and I would if I needed to) I'd use real shim stock to get it just right.

Mr. 66

I have a Cilo Pacer/Bass Sports, it has a French threaded bb.

I would look for cranks to drop on your current bb, but that's me.

Salamandrine 

Early on, the top end "Mighty" Sugino cranks were designed to be interchangeable with Campagnolo. This continued up to around the mid 80s, IIRC. A Mighty from the 70s up until the early 80s should fit your campy spindle fine, after that it gets a bit dicey. Any way you slice it, try and fit will be required.

Again, there were n't JIS and ISO tapers during this period. That standard was established later.

Wildwood 

I know this is a crass reply, by classic bike enthusiasts stds -- if you wish to install a JIS spec'ed crank onto an ISO bb spindle and are uncomfortable with taper angle differences, an affordable sealed bb replacement is usually available. Going the reverse direction is more expensive for new or NOS.


In addition to the different taper angles, I have swapped a double crankset for another double and found the inner ring to contact the chainstay. The difference was more than could be attributed to taper angles changing the 'effective crank length' (if you take my meaning). Not sure if this issue is worth my time to take precise measurements for specific combinations, as would take a fair amount of bike labor.

niliraga 

shims! i love it - and given the purely low-energy, recreational mission here I'm not ruling it out yet...

niliraga 

this might indicate that an early Mighty Tour might be a solution, if i can find one of those lying around...

niliraga 

yes, that's exactly my "something workable, on the cheap" quest at the moment. I'm not even sure i could get the Campy BB out of there, let alone find the right french-threaded cartridge in my parts bin...

repechage

A Campagnolo Swiss thread bottom bracket cup will be marked as French AND have a GA or G hand stamped or engraved for Gauche or LH threading.

But, yes there are smaller bolt circle cranks that are Campagnolo or of the Campagnolo "look" that will utilize the spindle without mod. or exchange.

scarlson 

I currently have, on my Vitus 979, some TopLine cranks and a Campy Nuovo Record BB. The TopLine cranks are purported to be JIS and I'm pretty sure the NR only came in ISO. I had a NR crank on it before, and it was pretty normal. I was a little worried, but everything is working fine. The TopLine sits about the same place on the taper as the NR. For what that's worth.

I did the beer can shim on my old Courtois I rode when I lived in Poitiers. Probably Carlsberg or 1664, I don't remember. The crank taper was deformed and bottoming out, so I needed some extra space. It was not great at first - I was always tightening it - but after a time it settled down. The beer can must be cut just to sit on the taper faces and not fill up the corners, otherwise the thing will be coming loose all the time.

niliraga 

good old Kronenbourg! right - so 4 small rectangles of beercan, each set on a taper "face" and fully framed by that face? i may try this and see how well it works. i dont mind at all abusing the cranks, as long as i dont do significant damage to the spindle's tapers. you reckon catering-thickness alum foil might be worth a first pass?

squirtdad

sheldon on bb removal..... the DIY bolt tool works IME

https://www.sheldonbrown.com/tooltips/bbcups.html

scarlson 

Right, exactly.

Foil is likely a different alloy than can. It's probably more malleable since it's meant to be bent and deformed in use, which may make it work better or worse. I really don't know. I will say that some of my beer can shims got cracks in them. The foil might be less likely to crack and more likely to stretch and bend, which could be a good thing. Only way to know is to try it.

JohnDThompson 

+1 this.

I just fitted a Sugino "Mighty Tour" (110mm BCD) arm onto a Campagnolo Nuovo Record spindle and it looks good.

Feldman

I've done that too--the originalMighty Tours with non angled arms, works great!