Fred's given a really good rundown of the BB length possibilities for the TA Tevano crank. It is hard to tell what bb length will give you the ideal chainline without eyeballing the sight picture from the freewheel to the chainrings, but I can offer the following info from back in the day:
The TA cranks (Cyclotouriste) used a slightly longer BB for a double than did a campy crank. The table I remember from the Phil BB sizing chart was:
112.5mm = Campagnolo pista 115 mm = Campagnolo double = TA single 118 mm = Campagnolo triple = TA double (campy "Z3" axle, TA axle ref 343) 121 mm = TA Triple (TA ref. 344)
However, the old rule of "try it and see" really applies, there are a number of different variables such as rear over-locknut distance, bb cup thickness, etc that make recommendations on BB spindle length only slightly better than pure guesswork. What we don't know is if the Tevanos have the same relationship between the spider flats and axle tapers that the Campy cranks do. remember even Campy changed this dimension in 1978 to conform to the (proven idiotic) CPSC regulations. Dale feel free to delete this posting anytime.
At any rate, I have had excellent luck with a 115mm Phil spindle for a TA Cyclotourist double and recommend that you start with this length on your Tevano setup. I also have a Campy triple BB cartridge with a 115mm spindle that I will sell cheep, if you can use BSC. The advantage of the Phil is that it can be adjusted laterally to get the chainline "just right" and can fit just about anything.
I suggest using the shortest axle length that will give no more than 5-7mm of clearance between the chainstay and give you symmetrical clearance when the crankarms are torqued to 250-270 inch pounds.
=========================================
Mark Petry
Expert on nothing with opinions on everything
mark@petry.org
206 618 9642
Bainbridge Island, WA, USA
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> > Additional info: Rear spacing= 120mm, BB shell is 68mm.
Sean,
Is the Tevano really a "clone" of the Campagnolo crankset?
I'm asking because TA specified the same bottom bracket
spindles for the Tevano cranks as they did for their other
cranks. And the spindle specified for track use was the #314,
which is 111.5mm long - but asymetrical, whereas the Campagnolo
Pista spindle is symetrical.
It is possible that a Campagnolo Pista BB will work; but
this will depend on whether your frame's drive-side chain stay
is suitably indented, and also on the size of your chain ring.
This might lead to the rare situation of having too narrow a
chainline at the crank. You'd have to measure...
So the T.A. model 314 spindle might still be your best
choice. Here are some other alternatives:
1) T.A. #344 spindle, flipped over. This would then be the
same as a #314 on the drive side, but the left side arm would
now be spaced a few extra millimeters to the left.
2) Campagnolo 112.5mm spindle - i.e. what you use on Record and
earlier Nuovo Record cranks.
3) Any Campagnolo 111mm _symetrical_ BB, including modern
Centaur and AC-H; but this has the same considerations as the
Campagnolo Pista BB.
4) Modern Campagnolo 115mm _symetrical_ cartridge BB. I.e. the
Centaur or AC-H pieces for modern Triple cranks. This should
provide essentially the same chain line as #2, above, but the
left side arm will be moved to the left a couple of extra
millimeters.
5) Modern Miche Primato Track BB. The 110mm model will have
the same considerations as #3. The 115mm model will have the
same considerations as #4. Note that the cups on these allow
you to play with the chainline and clearance a bit on the drive
side. But if you use the 110mm version, and slide it to the
right, you can reach a point where the left side arm rubs the
chain stay.
I hope this helps,
Fred Rednor - Arlignton, Virginia (USA)