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Thread: 700cc to 26"??

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    700cc to 26"??

    i found a nice cyclocross bike on ebay and was wondering if i could change the wheels to 26" if i ever had to change or replace them.
    would there be a problem, besides the v-brakes? would it work if i switched to disk brakes?
    thanks!
    -g

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    coprolite fietsbob's Avatar
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    WHY? N+1.. Don't like it as is?, sell it and Buy the Bike You want,

    [ Or if this is another Pre worry, and you didn't win the Bid, stop ]

    rather than do those changes .. it's a fool's mission.

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    The Recumbent Quant cplager's Avatar
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    Quote Originally Posted by glopez View Post
    i found a nice cyclocross bike on ebay and was wondering if i could change the wheels to 26" if i ever had to change or replace them.
    would there be a problem, besides the v-brakes? would it work if i switched to disk brakes?
    thanks!
    -g
    If you switched to disc brakes, you could go to 26" wheels, 20" wheels, whatever you wanted to. People do things like this on recumbent bicycles somewhat often. Without disk brakes, you just need to have brakes that would work.

    Cheers,
    Charles
    http://Charles.Plager.net
    http://RecumbentQuant.blogspot.com

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    Changing the wheel size may be possible but it is likely to change the handling of the bike, and result in increased pedal strike from a too-low bottom bracket.

    What is wrong with the 700C wheels? 700C is the standard size for CX, touring, road bikes, hybrids, and 29ers. You have practically unlimited tire choice (limited mainly by the clearance in the frame and forks), and the bike will work as it was designed.

    What are you hoping to accomplish with this change?

    Also, what model of CX bike is it and does it have mounts on the frame and fork for disk brakes?

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    Quote Originally Posted by cplager View Post
    If you switched to disc brakes, you could go to 26" wheels, 20" wheels, whatever you wanted to. People do things like this on recumbent bicycles somewhat often. Without disk brakes, you just need to have brakes that would work.

    Cheers,
    Charles
    I very much doubt you could use 20" wheels on a bike designed for 700C... 26 inch wheels would possibly work OK, 24" would likely put the pedals very very close to the ground, and 20" you would only be able to pedal 60 degress at a time to 'ratchet' the bike forward. Brakes are not the only consideration.

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    The Recumbent Quant cplager's Avatar
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    Quote Originally Posted by LarDasse74 View Post
    I very much doubt you could use 20" wheels on a bike designed for 700C... 26 inch wheels would possibly work OK, 24" would likely put the pedals very very close to the ground, and 20" you would only be able to pedal 60 degress at a time to 'ratchet' the bike forward. Brakes are not the only consideration.
    You're right. I'm thinking of short wheel base recumbents where there's no problem with hitting the ground.

    Cheers, Charles
    http://Charles.Plager.net
    http://RecumbentQuant.blogspot.com

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    coprolite fietsbob's Avatar
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    Drop the tail end several inches the head tube angle goes down too..
    even on a recumbent.

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    Constant tinkerer FastJake's Avatar
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    V-brakes? No. Disc brakes, it would work but what are you trying to accomplish? As stated a smaller overall tire height will change the handling and make the BB lower.
    Why "derailer" is the correct way to spell the gear-change mechanism: sheldonbrown.com/derailer.html

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    Senior Member cale's Avatar
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    A 26" wheel sporting a 1.75" tire has an axle height of only ~.5" difference to a 700c wheel sporting a 28mm tire. These sort of difference aren't significant enough to impact handling. It's about the same as moving from a 23mm to a 35mm tire on a 700c wheel assuming you had the brake and frame clearances.

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    Quote Originally Posted by LarDasse74 View Post
    I very much doubt you could use 20" wheels on a bike designed for 700C...
    Don't be so sure - I managed to put 20" wheels on a 26" wheel bike recently - I did have to use very short cranks, but it worked. Don't even ask how I did the brakes, it'll scare people.

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    Senior Member Lexi01's Avatar
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    Quote Originally Posted by Airburst View Post
    Don't be so sure - I managed to put 20" wheels on a 26" wheel bike recently - I did have to use very short cranks, but it worked. Don't even ask how I did the brakes, it'll scare people.
    How did you do the brakes?

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    coprolite fietsbob's Avatar
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    yea but that 559 -47 tire wont fit in a CX frame,

    made for a 622-32 tire, particularly the fork.

    fool's errand ..

    go get a hundred yard spool of waterline while you are at it.
    Last edited by fietsbob; 11-02-12 at 11:01 AM.

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    I let the dogs out AlphaDogg's Avatar
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    Quote Originally Posted by fietsbob View Post
    Drop the tail end several inches the head tube angle goes down too..
    even on a recumbent.
    The angle doesn't change if you're lowering the rear and the front equal amounts. Maybe I misunderstood what you said?
    Quote Originally Posted by Andrew R Stewart View Post
    Weird spell/word check. "***" is "***". I'll never understand this computer. Andy.

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    Quote Originally Posted by Lexi01 View Post
    How did you do the brakes?
    Sections of an old rim - I mitred them to fit across the fork blades and seatstays in the same kind of way that kickstands do, drilled out a spoke hole on each one to admit the centre bolts on the brakes, then bolted them in place with the centre bolts. The brakes are BMX sidepulls, but the levers are absolutely massive, so I can pull them by the ends and the braking's OK. The bits of rim stick out a couple of centimetres each side, so I put duct tape on them to reduce the chance of them killing me if I ever crash the bike. I need to do something less bodged when I next get the chance, I might cut the canti bosses off and move them down to the right height if I can borrow a stick welder.

    I don't feel too bad about cutting and welding on the frame, it's a BSO that was donated to the co-op, and it's severely rusted. It was in the "scrap pile" when I found it. The 20" conversion was mainly to see if I could. It works, and who the heck's gonna steal it?

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    Old fart JohnDThompson's Avatar
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    Quote Originally Posted by Airburst View Post
    Don't be so sure - I managed to put 20" wheels on a 26" wheel bike recently - I did have to use very short cranks, but it worked. Don't even ask how I did the brakes, it'll scare people.
    Quote Originally Posted by Lexi01 View Post
    How did you do the brakes?
    I'm thinking "Ted Shred"

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    Quote Originally Posted by Airburst View Post
    Don't be so sure - I managed to put 20" wheels on a 26" wheel bike recently - I did have to use very short cranks, but it worked. Don't even ask how I did the brakes, it'll scare people.
    The question that immediately pops to mind is not 'how,' but 'why?'

  17. #17
    The Recumbent Quant cplager's Avatar
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    Quote Originally Posted by LarDasse74 View Post
    What are you hoping to accomplish with this change?
    I am curious about this as well.

    I'm pretty sure you can probably change to 26" wheels. If you tell us why you want to switch, I think you'll get better advice.

    Cheers,
    Charles
    http://Charles.Plager.net
    http://RecumbentQuant.blogspot.com

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    Senior Member cale's Avatar
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    Possibly the OPer doesn't want his reasons debated. I'm not sure I'd want that either.

  19. #19
    The Recumbent Quant cplager's Avatar
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    Quote Originally Posted by cale View Post
    Possibly the OPer doesn't want his reasons debated. I'm not sure I'd want that either.
    You're quite possibly right. That being said, I really am just curious. I already live on the dark side (ride a recumbent) and am quite open to people doing non-standard things with bicycles.

    Cheers,
    Charles
    http://Charles.Plager.net
    http://RecumbentQuant.blogspot.com

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    Quote Originally Posted by LarDasse74 View Post
    The question that immediately pops to mind is not 'how,' but 'why?'
    The short answer is "why not?"

    The slightly longer answer is "it was a slow day at the co-op"

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    coprolite fietsbob's Avatar
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    The angle doesn't change if you're lowering the rear and the front equal amounts. Maybe I misunderstood what you said?
    Recumbents, predominantly, already have a small front wheel.

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    Senior Member Bat56's Avatar
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    Quote Originally Posted by glopez View Post
    ...if i could...would there be a problem...would it work...
    Quote Originally Posted by cale View Post
    Possibly the OPer doesn't want his reasons debated. I'm not sure I'd want that either.
    Pretty sure OP wanted to know about potential problems and in order to answer that the reasons for the modification, or purpose of the modification is needed.

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    Quote Originally Posted by fietsbob View Post
    Recumbents, predominantly, already have a small front wheel.

    Even if the angles don't change, the amount of 'trail' will. Head angle is only relevant in that it works with fork rake and wheel diameter to produce trail.

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    Senior Member Retro Grouch's Avatar
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    Quote Originally Posted by cale View Post
    Possibly the OPer doesn't want his reasons debated. I'm not sure I'd want that either.
    Does first and only post tell you anything?

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