I bought a 1985 Trek 400 earlier this year, and it has become my favorite bike. It looked unused, with just a few marks on the paint from where it was moved around in the garage over the years. According to the 1985 Trek brochure, geometry for the 400 and 420 are the same, and the tubing set is the same. Both came with 27 x 1 1/8 tires and the same DiaCompe brakes, so tire clearance may be similar.
I replaced the 27 inch wheelset with 700c. The rear hub is 130 and fits fine as is, no problems. The tires are 33 mm Jack Brown Greens. No way a bigger 700c tire would fit. Pretty tight at the chainstays and even tighter under the fork. I actually tried a Pasela 27 x 1 1/4 first and they were too big. I installed 2 Tektro R365 sidepull brakes from Riv. Both are front recessed brakes. The fork on my 400 is recessed and the rear brake bridge is not, so a few washers on the rear and the brakes worked fine. The 700c wheelset has the brake pads at the top of the slots. A 650b wheelset would probably work with these brakes. Pictures of my Trek 400, with several Riv upgrades, here https://flic.kr/s/aHsjXsYBGU Good luck! On Thursday, August 28, 2014 8:03:39 PM UTC-4, cbone97 wrote: > > So after selling my Sam (sniff sniff), I scored a 1985 Trek 420 with 27" > wheels. It's a beautiful lugged frame that looks like it was barely ridden > and I can't wait to get my collection of Rivy parts on it: SunRace > thumbshifter (singular, no front der), Dirt Drop stem, fancy drilled Tektro > levers, etc. > > Here's the hard part. I'm a hefty lad and need/want a fatter tire than > the fattest 27"ers made. The Trek has a rear hub spacing of 126mm and I > don't really want to cold set it to 130mm. At 126mm, options seem limited > to freewheel hubs. I'm ok with that, but all the prebuilt 700c 126mm > wheelsets have skinny rims for skinny tires. So it seems I need a custom > rear wheel - 126mm hub with a rim that will accommodate 38-50mm tires. > > If I'm going to have a rear wheel built on a 126mm hub, would it be > preferable to go 650b or 700c? Can I really get that much more air volume > with 650b tires? My rough measurements suggest that with 700c the rear > will fit 38mm tires. With 700c, I might? even fit a 50mm Big Ben on the > front a and a little Ben on the rear. While 650b theoretically will allow > a bigger tire, I'm not sure a 650b Big Ben will fit the rear, which might > put me > > Assuming that the Silvers will work for either size (reach the 650b rims), > which size might be best? I think either would be fine/ok, am I forgetting > anything? Should I REALLY not rule out cold setting to 130mm and going > with a freehub wheel? > > Thanks! > -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to rbw-owners-bunch+unsubscr...@googlegroups.com. To post to this group, send email to rbw-owners-bunch@googlegroups.com. Visit this group at http://groups.google.com/group/rbw-owners-bunch. For more options, visit https://groups.google.com/d/optout.
