Brake caliper upgrade

[Gareth Thomas]

Hi there,

I bought a pair of Shimano 105 calipers to replace the previous single-pivot calipers on my old
Trek, and have a question. The previous front brake had a dished washer that sat between the caliper
and the fork steerer, I guess this was fitted to counter the curved surface of the steerer tube.
When I first fitted the caliper I transfer this washer over, but only got about 4 turns of the
retaining nut, which I figured was probably not enough. So I removed the washer and got around 8
turns, which I feel a lot happier with, and a test ride using fairly heavy braking showed everything
seemed to be in order.

Does anyone know the purpose of this washer, will I run into problems not having it or is the
trade-off in a greater thread area worth having?

Thanks in advance.

 

[Sheldon Brown]

Gareth Thomas wrote:

> I bought a pair of Shimano 105 calipers to replace the previous single-pivot calipers on my old
> Trek, and have a question. The previous front brake had a dished washer that sat between the
> caliper and the fork steerer, I guess this was fitted to counter the curved surface of the steerer
> tube. When I first fitted the caliper I transfer this washer over, but only got about 4 turns of
> the retaining nut, which I figured was probably not enough. So I removed the washer and got around
> 8 turns, which I feel a lot happier with, and a test ride using fairly heavy braking showed
> everything seemed to be in order.
>
> Does anyone know the purpose of this washer,

It is, as you surmised, to make a nicer fit on the front of a curved fork crown.

> will I run into problems not having it

No.

> or is the trade-off in a greater thread area worth having?

Yep. You did just right.

Sheldon "Ride And Enjoy" Brown +--------------------------------------------+
| All the world's a stage and most of us | are desperately unrehearsed. | --Sean O'Casey |
+--------------------------------------------+ Harris Cyclery, West Newton, Massachusetts Phone
617-244-9772 FAX 617-244-1041 http://harriscyclery.com Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com