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I have a singlespeed/track geometry frame and I am after a fork that matches it.

Besides the diameter of the steerer tube (it's 1 1/8"), what should I be looking for in the fork specs to be sure about compatibility?

EDIT: Let me be be more specific about the actual fork+frame combination that I want to assemble:

Fork (Alpina UD Carbon Track Fork)

  • Droput lawyer tabs: No
  • Fork length Axle - Crown (cm): 36
  • Headset type: Integrated
  • Rake (mm): 35
  • Steerer diameter (inches): 1 1/8

Frame http://ride2rock.jp/products/bike.php?id=31411

2 Answers 2

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Frames are made with specific axle to crown and fork offset (rake) numbers in mind for the geometry to be as intended. There's typically a common, mainstream set of numbers, give or take a few mm, for each genre of bike, but manufacturers can and do go outside of them.

Typical for track are offset numbers around 40mm. It's pretty common to see track forks with the smallest axle to crown numbers of any 700c forks (call it 370ish although there's differences in how people measure), correspondent to the tight clearance, but it's not universal because there's variance in the height of the crown itself, plus a bunch of SS bikes are now intended for brakes other than short reach road calipers.

If you know it's a level top tube bike and you have no other information about what axle to crown it wants but you have a protractor and a yardstick, you could model it in CAD or otherwise do the math to figure it out. If it's sloping top tube and you have no other information about it, you're somewhat shooting in the dark, although you could still put the frame in CAD, assume the headtube angle is typical for its size and genre, and use that as a reference point to get your axle to crown. Even if you're a little bit wrong in your guess, that will still result in a bike with handling that's about right. (Note that there's a whole world of debate about front end handling geometry and there's plenty of room for different preferences and theories.)

Finally with integrated/internal headset bikes there's the mostly aesthetic consideration of the smoothness transition/line between the headset and fork. (Mostly because some would argue there's an aero difference.) There are some trends there and plenty of manufacturers that do it certain ways, but no broader standards or rules.

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The Cutter is a BMX style trick oriented fixed gear, not a track geometry bike.

The specs here show that the fork you plan on using is going to be shorter than the standardbut and BMX geometry puts the front end up higher than track geometry so it may even out. The fork length difference could cause a problem with toe overlap, or even the wheel not fitting if the tire is too large.

I'd recommend trying out the combo before buying, for sure.

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