Ultegra brakes - washer layout plus back nut too long ?

[maltloaf]

Hi,

I recently bought some Ultegra brakes second hand. They turned up and looked lovely so I thought no more of it.

My new frame arrived today so I started fitting them, but realised I have no idea where any washers go (if at all).

I presume the back nut goes through the frame/fork without a washer but then do you have a washer or anything before the main brake assembly ?

Also, the front brake seems fine but the rear has a far too long back nut, which is more than double the thickness of the brake mounting on the seat stays. I see on the shimano site that there are 3 different back nut lengths available but I don't have them. Does anyone have any idea what I could substitute in there ?

Back nut is #4 on the shimano doc http://techdocs.shimano.com/media/t...BR/EV-BR-6500-1681A_v1_m56577569830728758.pdf and there is a washer/spacer shown but not clear where.
Any guidance gratefully received.

The perils of buying secondhand gear I suppose...

Many thanks in advance.

Kevin.

 

[accountantpete]

The order is as you suggest -nut goes into frame and then on the other side you have a serrated washer (or two) and then the caliper.

The serrated washer (s) act as spacers and also prevent the brake from moving - you should have some off the old brakes or you can make a temporary one up out of sandpaper doubled up with a hole in the middle.

The nuts as you as come in three sizes - they do long ones for some carbon frames - you will find that a similar nut off an old pair will work.

 

[Globalti]

Any bike shop will have spare nuts in their box of bits if you take the bike and brake along.

Don't worry too much about the castellated washer; they just damage your paint anyway.

 

[maltloaf]

Thanks guys, I presumed it would be back nut > frame > washer > main brake body

My bike shop built bike with tektro brakes on just goes back nut > frame > brake body and the brake's slight movement has chipped the paint off my front carbon fork. I wondered if it was the cause to be honest.

I'll ask them if I can swap my long nut for a short one out of their box of bits.

cheers,

Kev.

 

[maltloaf]

If anyone's reading this in the future, for reference, I found a back nut from a v-brake block which looks like a double height dome nut but with an allen key fastening and fits the bill perfectly.


The brakes are £1 a pair at Asda !

 

[Globalti]

I've just stumbled across this: http://problemsolversbike.com/products/brake_nuts

 

[maltloaf]

Looks mainly geared towards USA residents but thank you for sharing.