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Old 06-23-10, 10:30 PM   #1
Eric630
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Adding front fork braze-ons. Will it weaken?

Well title pretty much states my question, basically wanting to upgrade a 70's Peugeot for touring and want to add a lowrider front rack, so I'd need braze-ons in the middle of the forks for mounts (already have eyelets near axle for lower mounts), now will this weaken my forks too much? or is it a safe thing to do?

Also on a side note, the axle dropouts seem to be just barely narrow of what I need to fit a modern axle, would grinding them ever so slightly wider do anything harmful?

Thanks in advance.
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Old 06-23-10, 11:17 PM   #2
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Tubus makes a Great Clamp on mount to do what you need Done , buy a set of those . They are nicely machined .

In general the Boss reinforces the hole , and the trick is to really clean and flux the metal and then Heat it with the torch Just Enough to melt the brazing filler.

dirty hinders molten brass flow, and minimal heating is best.

part 2, HAND FILE , buy a nice new sharp file. grinding takes off metal too fast for precision.
and a file is like a saw, it only cuts in one direction, It's not like sandpaper.
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Old 06-24-10, 10:47 AM   #3
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I'd advise against adding the lowrider mounts to your current fork, it's not likely to be cost effective. There are plenty of forks available for cheap, so I'd just keep an eye out.

It's also worth considering if you really need lowrider mounts; they can be nice if you have a heavy load, but for lighter touring you can easily make due without front painners.
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Old 06-25-10, 04:54 PM   #4
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I'd advise against adding the lowrider mounts to your current fork, it's not likely to be cost effective. There are plenty of forks available for cheap, so I'd just keep an eye out.

It's also worth considering if you really need lowrider mounts; they can be nice if you have a heavy load, but for lighter touring you can easily make due without front painners.
Yeah I thought about getting new forks to clear up some issues with the whole French threading and spacing bull****... but I read somewhere that it affects handling or something like that (can't remember) unless I read wrong?

haha I think I'll need 'em, doing a very long solo tour =P
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Old 06-25-10, 06:18 PM   #5
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Also on a side note, the axle dropouts seem to be just barely narrow of what I need to fit a modern axle, would grinding them ever so slightly wider do anything harmful?

Thanks in advance.
YES it will - axle may not grip properly, weaker. Cold set to wider hub.
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Old 04-04-17, 07:53 PM   #6
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I want to add these brake mounts to my fork. How much does reheating the fork weaken it?
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Old 04-04-17, 09:34 PM   #7
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My first thought is that some Peugeot forks are be made of pretty low grade seamed blades. I would not consider using them for touring with a front load.


But others were made of decent high strength alloy steel and just like current blades with today's stuff these old ones are very worthy of mods.


Lowrider top mounts don't need to be cross drilled. Hour glass stay mounts have been brazed on the outside of blades for many years.


Think about how a fork is made. It is initially brazed/welded as a fork then the braze ons are usually added as a second step. There is no real difference in results as to when this second step is done. Minutes or years... As always this assumes proper brazing techniques, set up/prep and such.


As to drop out slot dimensions- unless the drop outs are of an extremely slim design (and I highly doubt this) removing a mm or so of slot width won't matter. But doing so is easer said then done. Care must be taken to end up with a blade length symmetry and not too wide a slot to allow the axle to not sit consistently in one location. You're dealing with fork alignment, not a hard aspect to get right but also not hard to get wrong. While not as agreed to, filing down the axle to be able to slide into the current drop out slot is a less one way street then modding the fork is. Andy.
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Old 04-05-17, 07:17 AM   #8
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Zombie thread. You guys reopened a 7 year old thread but late info is still good info. As to the brake mounts, I wonder if the fork legs are laterally stiff enough to take the new loads from the cantis or V-brakes those adapters allow since it wasn't designed for them.

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Old 04-05-17, 07:31 AM   #9
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Lowrider top mounts don't need to be cross drilled. Hour glass stay mounts have been brazed on the outside of blades for many years.
Or, skip the braze-on entirely and just use U-clamps.
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Old 04-05-17, 07:37 AM   #10
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avhed open old thread with new question about canti/v brake studs:

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I want to add these brake mounts to my fork. How much does reheating the fork weaken it?
Should be OK, who made the fork? Can you attach a picture of the fork? Who will do the brazing?
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Old 04-05-17, 08:10 AM   #11
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Or, skip the braze-on entirely and just use U-clamps.

John's correct in that no brazing means no chance to screw up the blades. But I'll admit that I much prefer the cleaner mounting of braze on points compared to clamp on ones. Some racks don't have the mounting slots/holes which are compatible with "U" clamps so their clamps would be single bolt ones, "P" clamps which are far less ridged then a "U" clamp is.


As MR IGH reinforced, who's doing the brazing might say a lot about possible issues. Andy.
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Old 04-05-17, 09:04 PM   #12
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Or, skip the braze-on entirely and just use U-clamps.
Too ugly.
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Old 04-05-17, 09:07 PM   #13
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avhed open old thread with new question about canti/v brake studs:



Should be OK, who made the fork? Can you attach a picture of the fork? Who will do the brazing?
Sorry no pic.
1981 Columbus SL fork made by in town builder.
Braze ons to be done by another in town builder.
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