jdawginsc 

How bad would it be running a 113mm octalink spindle with a 109.5 Dura Ace crankset...? Italians are hard to find!

RobbieTunes

Well, the smaller front chainring will like it.

That's one of those things where you can simply try different things:
-See if you can turn it in "too far," and take up slack on the L with a spacer.
-See if it comes apart and you can reverse it, then deal with the Q-factor on the L.
-File off 1mm on the R end (would take awhile)

Once it's mounted, the inner chain ring will like it, for sure, as you've kind of eliminated the cross-chaining issue there. The outer, well, on the bigger cogs, it may complain on the larger cogs, as the cross-chaining is exaggerated. You also may have seat stay clearance issues on the outside cog, sing the big ring.

Trial and error is your friend, and there are no guarantees, but it would not be the first time, on a bike setup, where ignorance is bliss.

rccardr 

I have done it. Biggest problem is getting the FD to shift onto the big ring due to the out-of-spec chainline.
Mine had friction front shifting, so less of an issue. But still annoying.

KCT1986

What model of Octalink BB are you considering?

Thought the Octalink V1s were only available in 68/73 for the 112.5 (113) MTB length.

Fivethumbs

I would just bite the bullet and pay for the 109.5. Ultegras are on ebay for $90 and Dura Ace is $110 on ebay and Unversal Cycles. It's worth it because these BBs usually last.

mprince

I run an XTR 113mm Octalink BB on my Steelman with Dura-Ace crankset. I had to do this when I built the bike up to fix a chainline problem (I use the 2.5mm supplied spacer on each side of the BB). Works perfectly, if you buy the BB new it comes with several spacers and a chart showing the various chainline options. Bonus for me is that I need the extra pedal stance as I am a big guy, I also use the extra 2.5mm each side that my Time cleats allow for.

jdawginsc 

THere are a few floating out there...DA and Ultegra. Haven't seen a 105 out there in Italian and less than 118, which I assume is the triple... Not many though, other than the new ones...

One might pop up used.

Ironically, this was my rat-rod Faggin project, but got sucked in by some good bargains...

3alarmer 

.
...I guess maybe if the parts cost you enough you'll eventually decide it's worth painting it.

jdawginsc 

I've been chipping away at the chrome rust and paint grime...I haven't given up hope that there is a rat with a lion's heart under there.

Not sure how I keep getting sucked into the cool components...it was going to be a frankenbike!

KCT1986

DA & Ultegra, 105 (BB-5500) are 109.5 or 118, in 68 or 70.

The 112.5 & 116 length are XTR, M95x series, MTB. Never seen these in 70.

As far as I can recall, these are the only models that were made in Octalink V1. Other Octalinks were V2, which are not compatible.

jdawginsc 

That is good information to know since it will be paired with a Dura Ace 7700 crankset. What were the V2s compatible with?

KCT1986

The Octalink V1s are 7700, 6500, 5500 & M95x models. These are the only 4 that I can recall. Don't think that any other maker had V1 compatible BBs. Ritchey and/or Cannondale may have cranks that used the Shimano V1 BBs.

The V2s are mostly MTB (about 9 speed time frame), except for road Tiagra of a certain vintage. There may be other road line that used V2 but not many.

Shimano's upper tiers transitioned to external BB in the next generation.