Camplex

Just a simple question to confirm my suspicions .. I'm "going" to a cassette for the first time and am curious about what length BB to install in order to maintain a good chain-line. Using a 5-speed freewheel, I use a 123mm BB. I'll be putting in a 9-speed cassette and a modern 11-speed free-hub. The crank is a Specialites TA Pro-Vis-5 triple - 50/40/31.

I'm guessing I just continue to use the 123mm spindle but there are longer out there. Will a 9-speed cassette be considerable wider?

I'm only asking about the BB, not the rear spread - this is for a 130mm spaced bike.

Thanks in advance,
John

fietsbob

The width increase progression was 5 to 6 speeds then the spacing was narrowed to fit 7 in the width of 6..

the width for # 8 was added, keeping the cog spacing of the 7, after 8 speeds the cogs and the spaces between them were thinned
so 9, 10 and 11 are about the same overall width of the 8 speed cassettes ..

Or you could get one and Measure..



a Frame spread is required, as 8 speed requires a 130 (135 may be better) wide rear end, 5 only 120..


[you might check in with the C&V section ]





'/,

Andrew R Stewart 

I'll add that some of the answer is also in the chain stay length. The longer the stay the more acceptable slight out of line chain lines are. I never bother with trying to get exact chainlines on my own bikes. But I don't ride bikes with less then 42cm stays.


I will agree with FB's suggestion to use a 135 rear width. Makes for a rear wheel with less dish.


IIRC Shimano's 130 road cassette hubs are based on a 43.5mm chain line. One quick measurement will give you the front line. Andy.

JohnDThompson 

If you have the wheel and cassette in hand, I'd just mount it in the frame and see if the chainline is reasonably close already.

But you may run into another problem running a modern, narrow, riveted chain on the TA crank. I had problems with an 8-speed chain on a TA Pro-Vis-5 crank in that the chain would sometimes jam between chainrings. Since I only had six cogs in back, I just reverted to a wider chain and it works fine. But if you want to use a 9-cog cassette you may need to file the spacers between the rings so they're a little thinner to discourage jamming.

Camplex

Thanks. I'm guessing I just continue with the 43.5 chain-line I've maintained on the 5-vitesse. I'll post to the C&V section to confirm, I suppose.. Appreciate any and all feedback.

John - what FD were you running? I've used the cyclotouriste with 8-speed chains (with my old 5-speed freewheels) without issue but I don't think I've ever used a 9-speed chain.... Running the TA triple, I find old FDs work best, such as a Simplex SLJ, Huret Jubilee, or Campy NR Pre-CPSC...

fietsbob

Chain line is parallel to the center line of the bike , rear centers in the middle of the sprocket cluster

3 of 5, 4 0f 7, 5 of 9.. 6 of 11 or the middle spacer if the cog/speed count is 6,8,10.

Retro Grouch 

I doubt it makes as much difference as you are probably thinking. 5-speed vs. 11-speed doesn't really matter.

The dropout spacing is a fixed given and 130 mm is a common spec.

The big change is your crankset. Whatever BB spindle length is recommended for your new crankset, get that.

bulldog1935

I'm running my cyclotouriste as a triple with 7 in the rear on 126mm.

Vintage low-Q cranks are so narrow, chainstay clearance is usually a more important issue than chainline.
I will show my daughter's '86 Team Fuji running a comparably low-Q Sugino Mighty Comp crank with 9 in the rear on 130mm.
Only trick here with the wider chainline was I had to reduce the largest ring from 52T to 50T to clear chain rub when the chain was on the small ring and the small cog.