Tyrell

I was gifted a 1992 Trek 1420 by my girlfriend's dad and I'm working on getting everything up to snuff. It rides pretty well right now but it certainly needs a few new parts (middle chain ring, chain, cassette, cables, bar tape, etc.). I've found a bit of info on the Vintage Trek website but can't find any info on the bottom bracket. Anyone know what size/threads I need to look for?

Thanks!

well biked

Threading is English, 68mm. Use the same length square taper spindle that's on the bike now, if you stick with the old crankset-

BikingGrad80

If you tell us the model number of the crankset we could probably tell you the spindle length you will need. It is a deore dx according to spec. Look for some letter/numbers on back of the crankarm.

Actually from Sheldon's Website:

Shimano Deore DX Deore DX MT60Triple 122.5 Square
110/74 1990-1993

Looks like you need 122.5.

HillRider

I have a '92 1420 exactly like yours and I installed a BB-UN71 122.5 mm cartridge bottom bracket with the stock Deore DX crank when I replaced original cup-and-cone bb about 19,000 miles ago. The UN71 has a good chainline and both front and rear shifting has always been good with it. Maybe a 118 mm would be ok too but I never tried one.

I later upgraded the 105 7-speed dt shifters first to 7-speed RSX STI brifters and later to 105 8-speed STI brifters using the same crank and bb throughout with equally good results.

Tyrell

Thanks so much for all the help!! Unfortunately, I just got back from wrecking my motorcycle at at the track this weekend so it may be a little bit before I get to the roadie. But now I've got the info I need to at least get stuff on order. Thanks!!