Join Date: Apr 2009
Location: New Rochelle, NY
Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
Both brakes have identical threads. 6x1 has been standard for decades. Odds are there's a burr or some minor out of tolerance problem with the front bolt, and the long one is loose enough to accommodate it up to a point and the short ones aren't.
Take an eyeball down the nut, and see how far the thread goes. Or go to any hardware store and buy a 6mm bolt and nut. Use the nut to "dress" the front brake bolt's threads, and the bolt to dress the threads on the nuts. Use plenty of oil and work by degrees, 3 steps forward, one step back. Feel for heat, and if it warms more than hot tap water stop and rest it. Remember, do not force anything, gust go a bit farther each time.
BTW- you can use the same method with the parts you have, but using a commercial bolt and nut eliminates the risk of the bad part damaging the good one.
An ounce of diagnosis is worth a pound of cure.
“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin
“One accurate measurement is worth a thousand expert opinions”
- Adm Grace Murray Hopper - USN
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