Brakes and wheels question for old bike

secretsam
secretsam Posts: 5,120
edited November 2007 in Workshop
Tried posting this on Commute site, no replies...
OK, I've had enough of feeble old centre pulls on bike 2

But clearance is an issue: currently around 55mm centre to centre with fusty old 27" wheels, so I guess I'll need about another 5mm when I switch to 700c or whatever they're called today ( :roll: )

Any advice? Need something with bolts not allen keys

Also: cheap wheels - if they come with a cassette, can I use an old, non-index shifter on them?????
It's just a hill. Get over it.

Comments

  • Garybee
    Garybee Posts: 815
    Can't comment on the brakes but you'll be fine with the shifting on a cassette type wheel. As your shifters aren't indexed the difference in the cassette spacing won't matter.
    Hypocrisy is only a bad thing in other people.
  • yourmom
    yourmom Posts: 10
    55mm from what centre to what centre?
    27" wheels are 15mm smaller than 700C in diameter (so 7mm bigger from axle to rim tip)
    Need something with bolts not allen keys? But a bolt is fastening device, and allen key is a tool......

    How old is the shifter? What is it? It might not have enough rotational movement to pull enough cable to drive a mech through a modern cassette width.

    More info, be specific, I'll gladly help
    Its just a bike for ***** sake, not the space shuttle.
  • Phil Russell
    Phil Russell Posts: 1,736
    The rim diameter for a 27" wheel is 8mm greater than for a 700C (630 as against 622) so the braking area is 4mm lower at the rim on a 700C wheel.
    This means you need to be able to drop your brake blocks by 4mm in the brake arms for them to contact a 700C rim.
    I did this and had no real problem but the blocks were right at the bottom of the arms.
    Another route, and one I have done, is to get a set of long arm or deep reach brakes. I used Alhonga. They are not expensive but you need to get the correct depth ones; the measurements quoted are the range of drop they fit so if your distance from the cbrake pivot bolt in the frame is 55mm you need brakes that span this measurement.... I think I got mine from Spa Cycles. However, due to the distance from the pivot to the brake pad I am not convinced they are that much more effective than the centre pulls they replaced ... and they have no quick release mechanism whereas my old centre pulls did have. But then ... how often do you need it?

    Hope this helps

    Cheers, Phil

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