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I have a project bike. I made it myself from bits recycled. It is currently a single speed, although I'm thinking of adding gears to turn it into a bit of a commuter/excercise bike.

Before I do that, I really need to sort out the fit. It doesn't seem to fit me, or even itself very well.

Bike dimensions - 51cm seattube, 50cm top tube, chain stay 41cm. tires are 700x32.

The problems:

  1. The bike has a seat tube length of 51cm which seems right for me at 5'6. When i sit on it my leg is straight at the bottom of the stroke, However there is virtually no standover room.

  2. the bike seems pretty cramped horizontally, that is the handlebars seem too close to the seat. in fact i'm not sure if the top tube is long enough.

  3. The front wheel, despite being the right size to line up with the brake, seems to be way to close to the downtube, and as a result clips my toes sometimes when I'm pedaling. Does this bike even fit itself?

  4. both wheels are pretty tight through the brake. That's probably because of the chunky tires.

What have I done wrong? How can i get the bike to feel a bit less cramped?

an odd looking bicycle

enter image description here

  • If you have no standover (i.e. if your nads are less than at least an inch from the top tube), you need a different frame. – Batman Jul 4 '15 at 23:27
  • In the old days the rule was that the top tube should just touch between the legs. One inch of 'air' meant that the frame was too low. Philosophy changes! – Carel Jul 6 '15 at 18:26
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Adding to the answer by @mattnz ...

This looks to me like an old frame to me.

The steep headtube angle is supposed to be matched with forks that have more forward curve. And it should have drop bars.

Here is another Parleigh, built as a fixie (from here):

enter image description here

Notice the seat height, and the reach to the bars.

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The geometry of this frame looks odd. 622mm wheels are too large to fit comfortably in a 51cm frame. Usually sizes this small are made to compensate with very steep seat tube angle to let the rear wheel forward and very shallow steering angle to avoid toes clipping front wheel. This bike has been made the other way around and that is why it looks and feels strange.

  1. With saddle as low as shown in picture, the frame is too high for you. With horizontal top tube, there should usually be about hand's width of seatpost showing. The saddle should be roughly horizontal.

  2. Longer handlebar stem or less swept back handlebars will help.

  3. This is a problem with all small frames with large wheels. Is the fork the original one? Some older bikes came with steep steering angles and very high fork offsets. The offset eliminates some of the problem with toe overlap but makes steering twitchy at high speeds.

  4. 32mm tires are the absolute maximum size to fit inside short reach brakes. Normally the kind of brake is used with 23mm to 25mm tires.

Edit: @Will's comment led me to the idea that this bike could have been a 650B or at least converted into one. That would reduce the standover height and allow wider tires and also explain the strange-looking angles. Smaller wheels would lower the bottom bracket, so saddle would still look too low.

  • It's crossed my mind that i might have the wrong size wheels on it? could it be that i should have 26" wheels on a bike that old and small, and that would allow for more clearance between front wheel and bottom tube & toes and would lower the bike for more standover room. – Will Jul 5 '15 at 18:03
  • Hmm, probably not 559mm because that would need 30mm of extra brake reach but maybe 584 aka 650B? Hard to say without seeing the original fork or how much sideways clearance the rear triangle has. – ojs Jul 5 '15 at 18:22
  • i added an image of the rear brake / wheel clearance. not a lot. I might take it to the lbs and see what they make of this mess. – Will Jul 7 '15 at 17:32
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The bike was built as a racer and it looks you are trying to make it into a hybrid/Commuter and get a more relaxed riding position. This wont work as the geometry is wrong for that.

Have you tried with the seat more horizontal. As it is, it will push you forward. Its also as far forward as it will go - slide if back on its rails. At the same time raise the seat height and/or lower the handlebars - normally a road bike the seat is higher than the bars. If this does not work drop bars might help as would a longer stem.

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  1. If there's little stand-over space, then the frame doesn't fit you, and there's nothing you can do except get a new frame. Either get one with a shorter seat tube, or get a "compact" design with a sloping top tube. You can just stop reading here, but I'll answer your other points just because.

  2. You can move the seat back, or get a longer stem, or get handlebars that put your hands further forward.

  3. The fork you have is not the one that originally came with the frame, is it? The original fork probably had a higher rake, which would put the wheel further forward. Toe overlap is something you can learn to live with, though.

  4. As long as the tires aren't rubbing, there's no problem. If there's very little clearance, you just have to pay close attention to it, and make sure your wheels are true. Or get skinnier tires.

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