770c? New and unsure

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  • Ive been looking to buy a nice old racer and spend some time and attention on it, and i think ive found the right one. But it has 770cc wheels, and im not sure what this means or what to do about it? can i just put 700cc's on or do i have to do that thing where you basically bend the rear of the frame in? completley unsure.

    thanks.

  • Motorbike?

  • 770 will be related to the diametre rather than the hub spacing

    measure between the drop outs at the rear

    120 mm for track
    126 ish for road
    both of these are standard

    if you get anything else then it may need a bit of cold setting, squishing or squeezing

    but as I have been told steel will flex a bit so as long as you are within a cm or so it shouldn't be a problem

  • Sounds like a typo to me...

  • Just what I'm thinking, probably a typing error for 700c. This is the rim diameter, not the rear spacing. If it is an old racing bike it will probably have a rear spacing of 130/136mm. As Dicki said, steel frames will flex a bit, I had to prise my rear dropouts apart a bit to get my wheel in.

  • wouldn't happen to look like this would it?
    its a typo

  • could 770's be 29'ers ?

    although if it is a classic bike then 29'ers wouldn't even have been invented then ?

    if you go to sheldon browns website he has a full complete list of every wheel diametre possible and a description of the sort of bikes that would use them

    might be worth a trawl

  • Just what I'm thinking, probably a typing error for 700c. This is the rim diameter, not the rear spacing. If it is an old racing bike it will probably have a rear spacing of 130/136mm. As Dicki said, steel frames will flex a bit, I had to prise my rear dropouts apart a bit to get my wheel in.

    if it's an old road bike it should have a rear spacing of 126mm, newer will be 130mm. if it is the bike in the picture above then I'd have thought you'd be looking at 126mm. and almost certainly just a typo.

  • Like pajamas said, 126mm is road spacing, 120 track, 135 for mtb.

    29ers use normal 700c diameter rims I believe just a bit wider to accomodate massive tyres.

  • Like pajamas said, 126mm is road spacing, 120 track, 135 for mtb.

    29ers use normal 700c diameter rims I believe just a bit wider to accomodate massive tyres.

    wha???

    29er refers to a wheel diameter of 29 inches. 700C is just a little smaller than 27 inches. I fear you must be mistaken...

  • 29er's are just wider 700C diameter wheels

  • the '29' refers to to the diameter including the big fat tyre which is roughly 29 inches. The actual rim is the same diameter as a road rim and many people actually use them for 'brakless fixie skidder' due to their availability in non-brake surface versions.

  • wha???

    29er refers to a wheel diameter of 29 inches. 700C is just a little smaller than 27 inches. I fear you must be mistaken...

    ha, wrong.

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770c? New and unsure

Posted by Avatar for Tenderloin @Tenderloin

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