Tapered dropouts

jkallay

New Member
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My donor bike has (for all intents and purposes) the pictured fork above, with a close-up of the actual build below. The issue is that theres a taper from the body to the dropouts which leaves very little flat surface for the conversion's brackets to grab. For them to be flush against the dropouts (without causing them to angle inward and not have the necessary spacing) the brackets have to be at the very tip of the dropouts, such that the bolt is essentially flush with the dropout mouth. I'm concerned about a) the safety of the fork holding on to the front wheel by its fingertips, so to speak b) being able to get the brake pads to hit the rim when the axle is sitting so low relative to the fork.
Should I grind the fork down to eliminate the taper so that the bolt can be fully seated into the dropouts, or leave the fork as-is and find a way to fit the brakes?
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Charles.Plager

Recumbent Quant
I'm not sure I see the

I'm not sure I see the problem (I only see the top picture, not the bottom one).

My fork looks similar (I think) and I don't have any issues.

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jkallay

New Member
More pictures and explanation

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Here are some pictures that should help explain the problem.
The issue is the taper on the wheel side of the fork, which is the side the mounting flange of the bracket is supposed to go on. As you can see in the right-most picture, the amount of drop-out sticking out below the point where the fork starts to flare out is small. To clear that flare the bracket has to be tilted at a high angle, moving the flange that is supposed to go against the fork inches away. There's a bit of a cutout at the innermost mounting hole that would be helpful, except that at that point the bracket starts to bend outward.
 

Charles.Plager

Recumbent Quant
Oh... I think I get it now.

Oh... I think I get it now. (I'm sometimes quite slow).

Can you insert something in the bottom of the fork to help brace the bracket?
 

John Tolhurst

Zen MBB Master
Hmm, I havn't seen that

Hmm, I havn't seen that dropout design before. No easy answer unless you risk grinding the offending bit of the fork away. A different fork would be a better option.
 

Shahmatt

Active Member
The brackets are made of mild


The brackets are made of mild steel. If you can find a vice and rubber hammer you can quite easily try bending it to the shape you need. I had to do some bending for my conversion to work.

If the innermost hole is the best fit and the upper arms rest on the fork properly in this position, by how much does the bracket bend outward? If the angle is not too bad then you can try bending it slightly to the parallel position you need.

Another option is to try fitting the brackets on the outside (non-wheel side) of the fork dropout. You will then have a very wide wheel dropout spacing, so your axle will need to be long enough. Your bracket upper arms (that rest on the fork arms) will also be out of position but these can be bent inward to rest on the fork. This I did on my conversion fork (image below). But my fork is 75mm - not the usual 100mm, so the final dropout width (and necessary axle length) came out alright.

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jkallay

New Member
Thanks for your responses. I

Thanks for your responses. I think John is right--the right solution (in the spirit of using as much of the donor bike as possible) is to get that obstruction on the fork out of the way. I'll let you know how it works out.
 
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