Tandem Cycling - Trek T50 upgrades

I have a mid '90 Trek T-50 with a mixture of Deore DX/XT components, 21 speed I would like to upgrade with 8 or 9 speed gearing, with disk brakes on the rear. Can someone recommend a list of economical components in order to do this. I will probably need to upgrade the rear wheel as well. Also I am not sure if one of the new hydraulic disk brake will work. Thanks.

Depending on when it was produced, your Trek tandem may have either 140mm or 145mm rear drop-outs. Regardless, I would recommend going with a 145mm 8/9 speed rear hub even if you need to have your bike shop cold-set the drop-outs the extra 5mm if need be. A Shimano HF08 rear tandem hub is pretty economical and you could save a few bucks by building up a new rear wheel using the new hub and your old rim. Performance and Nashbar both sell economical cassettes but I'd recommend going with at least an XT grade rear derailleur. You should be able to find used or NOS 8 or 9 speed MTB shifters and/or integrated shift/brake levers on Ebay or at rec.bicycles.marketplace. For 8 speed, you probably wouldn't need to change your chain rings whereas for 9 speed you'd want to buy a square-taper 9 speed left-hand rear triple crank to replace the one you're currently using. It doesn't have to look the same but it does need to have crank arms that are the same length as the old one, i.e., most likely 170mm. Those things + a new chain and some new derailleur cables and you should be good to go.

For disc brakes, you'd need to use a Brake-Therapy adapter or have a frame shop weld on an I.S. disc brake mount to mate with an Avid BB7 mechanical disc. Personally, I think that would be a lot of money to throw at an old frame like the T50's and would probably recommend hanging an Arai drum brake on the bike instead if you feel you need more braking power than is provided by cantilevers.

Look for a better bike rather than investing lots of $$$ in upgrading . . .

Thanks for the input. One other question....do you know of a supplier for 134mm bottom brackets. I have only found Phil Woods.

Thanks for the input. One other question....do you know of a supplier for 134mm bottom brackets. I have only found Phil Woods.

Shimano offers a square taper cartridge BB in 127.5mm and Kajita has 129mm, either one of which should be long enough... 134mm is VERY wide for a BB axle.

You can find both of the aforementioned BB's at Tandems East
http://www.tandemseast.com/parts/brackets.html

PrecisionTandems.com or one of the other tandem speciality dealers and of course Harris Cyclery.com will likely have these as well.

If you have cup and cone (aka, loose bearing) BBs, Harris Cyclery has all the parts you'd need to replace whatever needs to be replaced with your choice of up to 136mm axles

http://sheldonbrown.com/harris/bottombrackets.html#axles