135mm hub in a 150mm space

OnYoLeft said:

Hi Everyone!

OK all you techies out there. I have been trying to find a 150mm 3-speed hub for
our 2000 Vision VR-85. After a year of searching and advise from some LBSs,
there is no such animal. However, a 135mm 3-speed hub is available from Shimano
and Sachs and will work with a 12-34 mounted on them.

My questions are:

1. Can I have a wheel built with a 135mm hub and tighten the snot out of it, drawing the chainstays in?

A club member did this and has had no problems with over 10k miles of loaded
touring on it. Last year, I was leery of over-tightening (squeezing) the
chainstays for fear of failing the structural integrity or placing washers on
the axle to make up the space.

2. Should I add a indexable bar end shifter for the 3-speed or is it better to
have all my shifting integrated with my brakes as they are now? I have Magura
hydraulic brakes on XT rapid fire shifters. I know that there is a set-up that
will accept hydraulic brakes, 3 speed front der., 9 speed rear der., and a
3-speed hub.

As I mentioned, a club member has this set-up on his Vision. He has a 3rd or 4th
generation frame. I originally thought that older Vision tandem frames were a
different width dimension between the chainstays. I don't agree with the
squeezing of the chainstays but it apparently works. It's only 7.5mm per side.

You can usually change the dropout width on chromo bikes by 10 mm without failure, but I’d be apprehensive about a 15mm change particularly since the R85 has only chain stays and no seat stays to support the dropouts. Given the history of Vision tandem frame failures due the monotube design not handling the tandem rider weight, I’d hesitate to do anything that might effect the frame integrity. I’d consider a longer axle with spacers even though the axle might be more prone to bending.

OnYoLeft said:

Hi Everyone!

OK all you techies out there. I have been trying to find a 150mm 3-speed hub for
our 2000 Vision VR-85. After a year of searching and advise from some LBSs,
there is no such animal. However, a 135mm 3-speed hub is available from Shimano
and Sachs and will work with a 12-34 mounted on them.

My questions are:

1. Can I have a wheel built with a 135mm hub and tighten the snot out of it, drawing the chainstays in?

A club member did this and has had no problems with over 10k miles of loaded
touring on it. Last year, I was leery of over-tightening (squeezing) the
chainstays for fear of failing the structural integrity or placing washers on
the axle to make up the space.

2. Should I add a indexable bar end shifter for the 3-speed or is it better to
have all my shifting integrated with my brakes as they are now? I have Magura
hydraulic brakes on XT rapid fire shifters. I know that there is a set-up that
will accept hydraulic brakes, 3 speed front der., 9 speed rear der., and a
3-speed hub.

As I mentioned, a club member has this set-up on his Vision. He has a 3rd or 4th
generation frame. I originally thought that older Vision tandem frames were a
different width dimension between the chainstays. I don't agree with the
squeezing of the chainstays but it apparently works. It's only 7.5mm per side.

I would keep looking for another solution.
150 mm is a very different spacing.
145 mm and 160 mm are not at all unusual for tandems.
Using 135 mm Over Locknut Dimension (OLD) for a rear tandem wheel is asking for long term trouble. The reason for the additional spacing is to make the wheel much closer to having equal support angles on left and right spokes. The result of equal and sufficient spoke support is a strong and durable rear wheel, where left spokes join in carrying "their share" of the load. Rear wheels have it tough to start with, and tandem service makes it even more difficult.