Absenth

I've been looking around and have noticed that 27" x 1 1/4" tires aren't exactly a popular size these days. That's what currently lives on my Vintage 520. It's also been mentioned that my wheels don't have stainless steel spokes, and the Hubs leave a bit to be desired.

I like the idea of having all the original stuff for my bike and will keep the wheels I take off. However I also like the idea of being able to buy pretty much any tire/tube I want off the shelf at any local bike shop. As well as maybe getting a dynohub to run a headlamp.

So my question is, how much monkeying around is it going to take to put 700c wheels/tires on my bike? I imagine I'll get a new rear cassette, the dynohub, tires, and tubes. Is it likely my brakes can be adjusted to the smaller diameter wheel?

Any advice on what wheel / tire size I should be looking at to replace the 27x1.25?
Last question would be, do you have any advice on a dynohub / light combo that's reliable?

mazdaspeed

I'm in the process of converting my '84 trek 520 to 700c. The cantilevers it has can't adjust down far enough. You'll either need to get shimano (deore? or something) cantilevers or go to long reach caliper brakes. The new tektro cantilevers don't adjust far enough for 700c wheels. Calipers will involve drilling the fork and rear bridge to accept the 8mm flush mounting bolt thing, and possibly removing the front cantilever bosses depending on how you go about it. Normal road wheels will fit on it, though, the brakes are the complicated part.

The wheels it has aren't particularly heavy or bad, but the helicomatic hub is a piece of crap and the corresponding freewheel will never shift remotely close to as well as a modern shimano unit will.

I personally like the 520 frame enough (and it fits me perfectly) that I'm going through the effort to do this, but it does require modification that will probably make the frame less valuable.

Also, if I were you, I'd skip the pointless dyno hub and just get a brighter, less complicated battery powered light.

Absenth

I've talked about getting a Surly LHT in a year or two anyway. I guess I'll stock up on a couple spare tires, and tubes now, and save pennies towards the Surly. If the helicomatic blows up between now and then I'll cross that bridge as it happens.

Thanks for the information though It was very helpful

illwafer

just fyi, your 520 is way cooler than an LHT.

keep on trekkin

Just put Vittoria Zaffiro 1 1/8" on my 77 TX504, and other than blowing the bead off because i pumped it up to 100 instead of 80, they're great. [and that happened in the living room, not on the road...]. I went back and forth in my head about upgrading, old spokes, straight [nonhook] rims, etc, but came to my senses and as long as it rolls great, which it does, i'm not gonna fix it... good luck!

ps. when i do upgrade it will likely be to more 27" wheels...

Absenth

More reason to leave it original and ride it.

I'd still like a modern bike to go with it though.

mazdaspeed

The 520 isn't especially rare or valuable, if you like the frame enough there's no reason not to modify it for your needs. I don't see any reason why the LHT would be better, it looks like the frame is heavier and made from inferior steel anyway. Furthermore, with long reach calipers and 700c wheels (which are smaller in diameter than the 27"), you'll have more than enough room to fit very large 700c tires and the braking will be better than with random old cantilevers anyway. IMO, besides keeping a bike worth less than $400 original, there's no reason not to just get a 700c wheelset and mod the frame to fit long reach dual pivots. Also, shimano makes a 11-28 freewheel which only costs ~$30 and will shift great combined with a new sram pc-870 chain, and it will work great with the half step gearing the trek comes with up front.

jacksbike

I understand that the Panasonic Pasela tire is readily available in 27 X 1 1/4 and 1 X 1 1/8. Why don't you just throw on a pair of those, rather than changing to 700C wheels ? You will definitely have a brake issue involved.

sailorbenjamin

Yeah, Paselas are great and inexpensive and available in 27". No muss, no fuss.