Question for Shimano sidepull owners: Brake bolt center shaft diameter
07-01-12 | 02:31 PM
#1
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Question for Shimano sidepull owners: Brake bolt center shaft diameter
Hello fellows,
I have a number of spare, nutted brake bolts for Dura-Ace BA-100 sidepulls, such as the example below. Unlike Campagnolo (or most anyone else), Shimano designed the first-gen DA sidepulls so that the shaft that supports the arms on the brake bolt is 6.5mm - 0.5mm larger than standard (though the threads in front remained 6mm):
These bolts have made me wonder about later-production, sidepull Shimano calipers, such as the Dura-Ace BR-7400, the BR-1050 (105), and the BR-6207/6208's/BR-6400's from the 600 family. Specifically, I'm curious whether they are also built to the 6.5mm standard.
That's where you fellows come in. I don't have a single Shimano sidepull brake caliper to my name at the moment - but perhaps one of you fellows do, and wouldn't mind temporarily taking it apart to check. If so, let me know the diameter and length of the shaft (arm thickness is also an issue). In short, I'm curious whether it might be possible to use these bolts to convert these 1990's-era, recessed-only brakes into nutted configurations.
-Kurt
I have a number of spare, nutted brake bolts for Dura-Ace BA-100 sidepulls, such as the example below. Unlike Campagnolo (or most anyone else), Shimano designed the first-gen DA sidepulls so that the shaft that supports the arms on the brake bolt is 6.5mm - 0.5mm larger than standard (though the threads in front remained 6mm):
These bolts have made me wonder about later-production, sidepull Shimano calipers, such as the Dura-Ace BR-7400, the BR-1050 (105), and the BR-6207/6208's/BR-6400's from the 600 family. Specifically, I'm curious whether they are also built to the 6.5mm standard.
That's where you fellows come in. I don't have a single Shimano sidepull brake caliper to my name at the moment - but perhaps one of you fellows do, and wouldn't mind temporarily taking it apart to check. If so, let me know the diameter and length of the shaft (arm thickness is also an issue). In short, I'm curious whether it might be possible to use these bolts to convert these 1990's-era, recessed-only brakes into nutted configurations.
-Kurt
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Last edited by cudak888; 07-01-12 at 02:46 PM.
07-03-12 | 09:51 PM
#2
curmudgineer
Joined: Dec 2009
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From: Chicago SW burbs
Bikes: 2 many 2 fit here
Stand by my friend. I'm travelling at the moment, but I'll have a chance to measure what I have on hand no later than Saturday. What I have on hand are these:
and these https://velobase.com/ViewComponent.as...m=117&AbsPos=1
minus the 105 branding and mounted to my 1989 Peugeot Versailles. I also have their poor brethren, https://velobase.com/ViewComponent.as...=117&AbsPos=37
long reach version, take-offs from said Versailles. Are any of these specifically of interest, or should I measure all of them? I already know that the pivot bolts interchange between the 105s and the Exages, as I had to swap them around to get the right length on at least one of them. I also had the other set mounted to the bike at one point, and everthing seemed to be interchangeable.
and these https://velobase.com/ViewComponent.as...m=117&AbsPos=1
minus the 105 branding and mounted to my 1989 Peugeot Versailles. I also have their poor brethren, https://velobase.com/ViewComponent.as...=117&AbsPos=37
long reach version, take-offs from said Versailles. Are any of these specifically of interest, or should I measure all of them? I already know that the pivot bolts interchange between the 105s and the Exages, as I had to swap them around to get the right length on at least one of them. I also had the other set mounted to the bike at one point, and everthing seemed to be interchangeable.
07-03-12 | 10:03 PM
#3
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Thanks for the offer, Geoff - but one of the other forum members emailed me with specs on his 7400 calipers; turns out Shimano standardized to the 6.0mm size shortly after. The B-210/BA-100's are the only calipers to use the 6.5mm shaft, apparently.
-Kurt
-Kurt
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