Jd512k

Hello all. Newbie here.

Rebuilding a 90’s Bianchi Campione (can not post photos yet per forum rules...).

Details - All Campagnolo (Mirage/Avanti). 8sp/Double Mirage Crank. 111/68 English (1.37/24) BB.

Question - Purchased a Mirage triple crank (son has the identical bike, his has the triple, mine came with the double...), do I need to replace the 111 BB with one that has a longer spindle or will the 111 work with the triple? Additionally, is the the Avanti front derail adjustable to accommodate a triple?

Thank you in advance! So glad to have found this forum.. first time really tearing into a bike and definitely need all the advice, tips and wisdom you all have to offer here.

T-Mar

The 111mm bottom bracket was intended for double crankset and also triple crancksets when used with frames having a 28.6mm seat tube. There was a 115.5mm bottom bracket intended for triple cranksets when used with frame having a 32mm or 35mm seat tube.

Avanti had a dedicated triple front derailleur. The double version had a claimed capacity of only 15T and most Campagnolo triple cranksets of the era had a 20T differential .

Old Fireleg

Hi,

I have no specific experience of the triple rodie myself, but I think Campa didn't accidentally offer the 115.5mm BB at the time along next to the standard 111mm. Expected, that the chain line is being moved, even if you can mount the triple on the 111mm (which I strongly doubt). FD and RD were also offered separately for the triple. In these facts the total capacity has significance. At the FDs are 22(3) vs. 15(2). I don't know, but obviously other forms of guides solved this problem. I do not know that your mixed system can be used with reduced services or total collapse. Obviously others will comment later, who have specifically encountered this problem.

merziac

Welcome aboard, glad you found us. Go around, say "Hi" and or comment on any post for 10 in two days, good ones and lots of them will help us help you which we are happy to do.

You can also post pics to the gallery that we can merge for you.

Good on ya for taking this on, it can be one of the more challenging valuable learning experiences working on bikes and will serve you well from here on.

Choke 

As has been said, you need the longer spindle. My suggestion is to buy the Centaur BB; you can find cheaper Campy 115.5 BBs but they aren't as well made IMO. Also, the cheaper version (Veloce) takes its own tool to install whereas the Centaur uses the standard Campy tool which also works on the cassette.

Jd512k

Thank you, T-Mar!

Seat tube is 28.6mm, except at the weld/shell where it is slightly oval, which measures ~31.5. Assume per your info, the 111mm spindle will work?

Regarding the FD... the triple Campy is a 52/42/32 (20T differential as you stated), therefore I do need a dedicated triple FD, yes? How do I source/identify a triple FD? This Avanti FD has absolutely no part #’s or identifying marks other than the Campy logo, “Avanti” & “Made in Italy”. Additionally it is not a clamp on, it bolts to a tang welded to the drive side of the seat tube. Have yet to find one like it online.

Thanks so much for the help! Really appreciate it.

Fair warning.. the crank set conversion is just the beginning 😁. Have questions regarding headset, quill stem, OA bath, hubs... cassette... but those will have to wait lol.

Jd512k

Merziac, thank you! That’s a great idea! I’ll get to saying hello and posting so I can attach pictures to this thread! Thanks!

Jd512k

Ive seen the the Centaur BB and considered it, but if at all possible I want to stick with all original parts on this build. The only deviation being the double to triple crank conversion, (however this bike came with that option) and i am replacing the Avanti shifters with a set of Mirage shifters.

Jd512k

Studying the closeup pics I took of my son’s identical bianchi (only difference between his and the one I am rebuilding is his is an 8 spd triple and mine came as an 8sp double)... I see no difference in his RD and mine at all. I do see that his FD is indeed a different version though.

Forgive my ignorance... how is the RD affected by a double vs triple crank set?

Old Fireleg

The triple has the advantage of extended gear. This is a convenience service. It is very rarely used by professional riders (perhaps the first and most famous example of this is G. Battaglin's 1981 Giro victory). With the appearance of the third chain ring, the difference between the smallest and largest chain ring's number of teeth increases dramatically. In your case, 52-32 = 20. For a normal double this is approx. 53/49 - 42/39. If 53-39 is taken then it is only 14 as opposed to 20 on the triple. In chain wrap, the front and rear capacities add up.

Campa mid'90 standard:
Double
RD total cap.: 26 and max. sprocket 28
FD total cap.: 15 and max. chainring 54

Triple:
RD total cap.: 37 and max. sprocket 28
FD total cap.: 22 and max. chainring 52

From this you can read how much more freedom gives the triple for you choosing a gear. Triple extreme numbers of cogs cause increased chain wrap. Technically, they can do this with a long cage RD. Here is a link here that describes it much better than I would know.

chain wrap capacity ? CanooterValve

T-Mar

Yes, according to the Campagnolo catalogs of the era, the 111mm BB will work with a triple, provided the the seat tube is 28.6mm (at the front derailleur mount).



Campagnolo triple front derailleurs of the period are identifiable by five characteristics, though not all are apparent unless viewed side by side with a double front derailleur:

1. The parallelogram linkage is longer, for the greater throw required with a triple crankset.

2. The nominal cage width is wider to accommodate the greater chain angles of a triple crankset.

3. The outer cage plate has an an indent along the lower edge to facilitate chain derailment due to the wider cage.

4. The inner cage plate extends lower than on a double to facilitate chain pick-up on the small chainring due to the greater differential in chainring size.

5. The cage curvature on the triple is slightly tighter, as it is typically used with a slightly smaller large chainring.

Most manufacturers tended to use clamp style mounts for triple front derailleurs, as they are sturdier. However, Campagnolo did make a braze-on version of their Avanti triple front derailleur. So, while they may be harder to find, they are out there... somewhere!




Campagnolo derailleurs of this era, for a specific group, had the same large cog capacity whether they were for a double or triple chainring setup. Consequently, the bodies are identical. However, since the triple version has to wrap more chain due to the greater chainring differential, it should have a longer cage.

Jd512k

T-Mar, Thank you! Great info, knew I was in the right place! Really appreciate you taking the time to reply.

Just to clarify - to do this conversion from a double to triple crankset, I'll need to find the appropriate F & R derailers and can in fact use a 111/68 BB, yes? Next question would be the chain... Thinking it though, given the tooth count of the triple vs. double, will the chain for the triple need to be slightly shorter or will the long cage RD compensate? Trial and error?

This project would be quite a bit easier if I had access to my son's Campione, however, he (and his bike) are in Arizona and I am in Washington... and yes indeed, a picture is worth a thousand words!

Thanks again,

~Jon