I have only one Mod 93 with a chainguard, I think, and I don't have it handy. Does that setup include spacers between the chainguard and outer ring? With the triple setup you will need spacers to separate the inner ring from the middle ring. The Sugino bolt set includes these.
38T is as small as you can go with a 122 BCD, I think. If you want smaller, you can go to a Stronglight model 99. That's an 86mm BCD and chainrings were available down to 28T, and maybe even a little smaller than that. Harris still lists some Mod 99 rings, and it's possible Stronglight is still making them. The Model 99 was often configured as a triple, whereas Mod 93 triples were a little rarer. The same Sugino triple bolt set should work for the Mod 99 as well.
Model 93 usually had steel dustcaps with a hole for a hex wrench. BTW, newer (post-1982) plastic Stronglight dust caps won't fit, because in 1983 Stronglight changed from their own unique 23.15mm crank extractor thread to Campy-compatible 22.0mm extractor thread. This also means you will need a Stronglight crank extractor - Harris sells some made by Stein Tools, although they are not cheap. DON'T try to pull a Stronglight 93 crank with a TA extractor or the TA end of the old reversible Park extractor. TA was 23.0mm - close but not the same. Sometimes you get away with using the TA extractor, but other times you ruin the Stronglight crank extractor thread.
Regards,
Jerry Moos Houston, TX
Rich Pinder <rpinder@usc.edu> wrote: Thanks Jerry for the info. Indeed.. I was reading the 'Center-Center' column from Sheldons page. 122 BCD is it as you suggest.
Thanks for the tip on the bolts - I do think these ones I have will work, as the chainguard looks same thickness as the ring. If the ring I find is exact thickness as the original ones, it should work well. Wish there was something smaller than 38 workable - but this will be goin in the right direction !
I've seen a few websites which list the newer rings - but none with photos. I'm hopin the 'look' is somewhat compatible with the crank. We'll see.
Thanks for the bolt info.
Did the Stronglight's come with their own dust caps ? (forgot I'll need to find a pair of them as well !)
Thanks Rich Pinder Van Nuys, CA
Jerome & Elizabeth Moos wrote:
>The cranks in the photo are indeed Stronglight Model 93. The BCD is 122mm. Perhaps your 71.7 is hole-to-hole? Stronglight still makes rings for these, including 38T. The new rings aren't quite as nice as the old ones, but they work fine. Harris Cyclery sells the rings, although they might have to order 38T if they don't have it in stock. They ordered several 38T for me a few months ago. It is possible the chainring bolts used by the double with chainguard will also work for a triple with no chainguard, although I've never tried that. What does work is the Sugino "old style" triple bolt set. These have no markings on the bolts (at least none visible from the outer side of the crank). The old Stronglight bolts were also unmarked, so it's very difficult to tell the Sugino bolts are not original. I've personally set up a model 93 as a triple with a 38T small ring using the Sugino bolts, and this setup works fine. The bolt sets are distributed bt Quality Bicycle Products.
> Their catalog # is CR1202. QBP is one of the largest bike parts wholesalers in the country, so Harris, or just about any LBS, should be able to order the bolt sets for you.
>
>Regards,
>
>Jerry Moos
>Houston, TX
>
>Rich Pinder wrote:
>I picked up a Stronglight crank a while ago after someone mused about
>the possibilities of converting it into a triple.
>It has a 'protective' ring that sits in front of the large ring. So
>there are positions that three rings could mount.
>The name on the back of the crank is 'Modelo Depose' - and I see
>reference on the net to this name being also in the '93' family. BCD is
>71.7.
>
>Sheldon's page mentions that Stronglight rings in this size go down to
>38 teeth (yes ?) - my current rings are 52/45.
>
>If anyone has a used (or new) STRONGLIGHT ring, I'd appreciate it.
>
>Here's a picture to compare with: *http://tinyurl.com/b5jjk*
>
>Has anyone ever tried to convert such a crank over to a triple?? Would
>there be a BB / Axle that would compensate for the spacing changes ?
>
>Appreciate any thoughts you could give.
>*
>
>Thanks,
>
>Rich Pinder
>Van Nuys, CA
>*