So, I'm trying to figure out two things with regard to this crank (https://imgur.com/gallery/mNXOebn)

1. What's the actual model? It doesn't fit the Velobase listings for either 'Sugino Mighty' or 'Sugino Mighty Tour double' since it doesn't have the spider cutouts. Anyone good with date codes?

2. Related to the above, is this likely to have JIS or ISO taper?

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It is the original version of the Mighty.

When found OEM on a bicycle length is often 165mm. Alternately, 171mm was also available.

BCD is 144mm.

The red anodised dustcaps seen in the photo have become sought after/collectible.

Taper is JIS. There was no ISO at this time.

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Pic assist -



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the Mighty Tour was the 110 bcd.. so that is a road chainring 130 or 144, I forget which.

The Sugino Mighty Tour was and is 110 BCD. I think it originated that size. Not sure. They still make the Mighty Tour, though the name seems to have been kept mostly to indicate 110 BCD, rather than its intended use.

The Sugino Mighty Competition was historically 144 BCD IIRC. It was campy compatible, at least in the 70s and 80s. I don't think they make it anymore for road. The Mighty Comp is still sold as as a single chainring track/fixie crank, but now it's 130.

To be more specific, it a Sugino Mighty Competition with arms manufactured in July and September 1971, so this would have been used a 1972 model bicycle.

My understanding is that the 1st generation Mighty crankset did not have flutes on the spider. These were added when it became the Mighty Competition. The Mighty Competition Custom had drilled out spider flutes and chainrings.

Edit: It looks like the Mighty was also 151mm BCD as I cannot find references for chainrings less than 45T. So,the Mighty Competition might also have seen the transition to 144mm BCD.

Minor correction, it uses the Sugino Mighty taper, which is very close to the early Campagnolo Record taper (Of which the Mighty is a copy) It's closer to modern ISO than JIS. The JIS taper is essentially identical to the Sugino Maxy taper.

Yes, this is a Mighty Competition crank. IIRC, only the track version used the 151mm BCD; road cranks were available in 144mm BCD. OP will need to meeasure to be sure.

Yes, close to modern ISO taper:


Source: Sutherland's 4th Edition

I'd agree with this except I've owned at least one 151 Mighty Comp ring in 3/32".

FWIW, I have a Zeus chainring, clearly stamped PISTA, but for 3/32" chain. It's a crazy world out there.

So far as I know, Phil Wood never made a Campagnolo (that is, Campagnolo pre-ISO, before 1994 or so) taper. When they had either ISO or JIS, they'd recommend JIS for a Campagnolo crankset. I've got both Campagnolo and Sugino Mighty spindles, and they measure so close that the manufacturing tolerance is a wash. They're more alike than the difference between them and JIS spindles, meaning that the JIS spindles are always somewhat "stubbier" than they are.

I never noticed the different taper end widths for Stronglight, Nervar, Galli, ISO shown in the Sutherland's clip above . . . kinda wierd! Is the presumption that the right (drive) socket will wear more than the left? And so needs a stubbier spindle taper end?

I wouldn't try to use an ISO taper spindle with a Sugino Mighty or Campagnolo crank. By the time it's tight, especially with a bit of wear to the sockets, you might end up with the spindle bottoming on the crank bolt washer. A good way to check fit is to tighten a crank up to proper torque, and then remove the crank bolt. See how much clearance is left between the end of the spindle and the land on which the bolt washer seats. If you don't have 1.5 or 2 mm, I'd say the spindle is not stubby enough. If it's over 4 mm, then you have to decide whether you're comfortable with that. My experience has been that even with a Sugino or Campy spindle for those cranks, the clearance is not that much. ISO just makes it worse. Your, and others', mileage may vary.

I have several sets of Mighty and Mighty Tour cranks installed on Origin8 ISO bottom brackets, and find they fit very well. When torqued to ~25-30 ft-lbs they have 2-2.5 mm from the spindle end to the face of the crank bolt recess. In contrast, I've tried Shimano UN-54 spindles and wasn't happy with how little engagement there was. I would estimate there was ~6mm before they would bottom out, and only ~10mm of engagement. Probably safe, but maybe not so secure. I would worry about ruining the taper for proper spindles down the road.

FWIW, Phil Wood did make Campagnolo compatible BB BITD. They had one for campy, and one for TA/Stronglight. That was as complex as it got. Campy compatible included Sugino Mighty. Correction, now that I think about it, and looked in my old catalog, actually they were the same except for length. The good old days....

All had asymmetric spindles, which made for a much cleaner installation than the current symmetrical variety, which leaves open threads showing on the drive side.

I have a Mighty Competition crank. It's 151BCD for track and is stamped on the back 168 M14.
168 is the length. Any idea about M14? It does not match the date code pattern of velobase.

Could mean M14 pedal thread AKA French thread.

I recall a collection of 151 BCD Sugino chainrings at Euro-Asia Imports back in the ‘80’s. They were dusty then and I don’t think any were sold while I was there.

Presumably they were transferred to Ben’s Cycle last summer.

M14 for french thread makes sense. The crank was mounted on a french bike with a Sugino MS-68 STRONG axle and 35x1mm cups.
It must have been rethreaded because it came with Campagnolo 9/16" pedals. When I try to bind a french pedal, it is loose.
Does the absence of date code indicate an old model?

The older cranks have date codes.
Tom Marshall (T-Mar) provides this description of the NN-NN Japanese codes:

"The Sugino codes with format NN-NN appear to be based on the Japanese Imperial Calendar. Whenever a new emperor took the throne, a new era was officially declared. On December 25 , 1926 Emperor Hirohito ascended to the throne and chose the the name Showa (radiant peace) for his era. It ended on January 07 1989 when Akihito took the throne and the Heisei (peaceful accomplishment) era began. Thus 1926 is year 01 of the Showa era, 1927 is year 02, up to 1989, which was Showa year 64 and Heisei year 01." I stumbled across this when I was trying to decipher the 47-12 and 48-1 codes on the Sugino crankarms A little investigation into Japanese culture turned up the logic in the preceding paragraph and when applied to my cranks, the manufacturing dates became December 1972 & January 1973."

I never realized that! Fascinating. That makes my set February 1972, both L and R. Date code 47-2.

I suspect my pista crank is from before 1972. It has no date codes, just 168 M14.
Even if date codes were already used in the 60's maybe they were not always applied to all models?