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rousseau
10-22-2017, 02:14 PM
My current project is a town bike/winter beater in the form of a 1979 Peugeot Super Sport that I'm updating with parts and wheels laying around. Got the LBS to put a derailleur hanger adapter claw on the dropout as per the photo below, but now my problem is that the lock ring on my Campagnolo Khamsin rear wheel is rubbing against the nut holding the claw in the dropout.

https://i.imgur.com/ohnCvsx.jpg

I'm thinking of getting a custom-made washer done at my friendly local machine shop to slide onto the axle on the cassette side in order to push the axle nut out a further 1 or 2 mm proud of the lock ring so that it clears the adapter claw nut. Does this sound like a decent plan?

The only potential problem I can see is that it's tough enough squeezing the 130 mm wheel into the rear dropouts on this old frame, which seems to be about 125 mm in width in actuality. Pushing the wheel to 131 or 132 mm might make things even more difficult.

Or is there a better way?

parris
10-22-2017, 02:43 PM
How much is it rubbing by and where? You may just be able to dress the nut down enough to clear the lock ring with a file.

sales guy
10-22-2017, 02:44 PM
My answer would be to put a washer in the axle to space it out more. Which you've mentioned. And while tough to squeeze in, it's a steel frame. you're safe doing so. If you wanted to make it easier, have someone spread them past the 125/126mm they are currently.

what you are having a super common problem when upgrading older frames.

Peter P.
10-22-2017, 03:05 PM
Is the adapter steel or aluminum? If steel, have it welded to the outside face of the dropout, then you don't need the nut at all. It's a beater bike so there's no need to be fastidious about it.

rousseau
10-22-2017, 05:53 PM
Thanks for the replies. I like the idea of filing down the nut a bit. I think I might try that.

rousseau
10-22-2017, 09:04 PM
Filing did the trick. I think I wore it down by almost a millimetre. It now spins free and easy.

The collective paceliners' wisdom saves the day yet again!

dddd
10-23-2017, 03:54 PM
I've setup quite a few rear hubs with custom axle spacing for updating old bikes to 6 or 7 speed freewheels, so I have dealt with this issue on several occasions.

Firstly, if the contact drag is not so heavy as to put a dangerous bending load on the dropout, then riding the bike a few miles will create clearance in the form of a groove in the nut and a little metal rubbed off of the offending freewheel or cassette protrusion.

From there, one can then remove the wheel and slightly enhance the now-visible wear pattern with a small stone on a rotary "Dremel" tool, so that the rubbing won't resume when the wheel is perhaps reinstalled with a slightly different axle position.

Those nuts are made of good steel, the bolts as well. I have taken a lot of metal off of some of those nuts without impairing their function one whit.

I am always trying for a minimum of "axle overhang" on any freewheel rear hub/wheel that I am setting up for use with a given width of freewheel, so removing metal where it gets in my way has become something of a habit.
Taking this to the limits, a narrower chain further increases needed clearance when there is contact caused by the chain itself, such as at the lower end of the seatstay.