Mechanical Question - CX Brakes

[Jason E]

Having trouble setting up my Avid Shorty Ultimates on the back of my Planet X IF. I've done this before on my Stigmata with no issue.

I know about the different spacers, but with either combo it is bottoming out. The posts do not APPEAR to be more than 21mm.

Ideas, input, clever quips?

[echelon_john]

take a couple of mm off your bolts with a bench grinder and give it another shot?

[Jason E]

I may have not been clear. The bolts are not bottoming out, the body of the brake is not short enough, so when the bolt is tightened, the brakes do not move.

Thanks,

Jason

[echelon_john]

Remove most of the Avids from your frame with a bench grinder, then install some TRP Mini-Vs? ; )

Hey, you said quips!

[Jason E]

:)

[pavel]

you could potentially machine some bolts in such a way that part of the bolt's head fits into the stud without torquing down on the brake, although that seems like it might take some finesse and special tools.

[Hindmost]

Appearantly there are different lenght studs.

From another forum:

"After measuring a bunch of studs I had laying around, I discovered my Avid Ultis used the "Pre-2008" length. From PMW's site:

For pre-2008 Shimano brakes, ask for our longer post, BR2014, as it allows 1/32" more room under the brake pivot."

[zennmotion]

It sounds like your bolts are too short and they bottom out. Just a ghetto idea, but what would happen if you were to drop something small (and retrievable) in to the hole in the post (stud)to make it effectively shorter, like a front hub bearing? Or maybe snipped off spoke heads? Try it and see. But maybe this is why I volunteer wrenching at a co-op and not a high end shop...

BTW I love my cheap and effective Tektro CR720s on their 5th cross season on 2 bikes, lots of clearance, easy set up, effective braking (with good aftermarket pads). Why pay for bling, especially if it doesn't work?

[jds108]

How about two of avid's washer's rather than just one on each side (to effectively increase the length of the post)?

If the brake is getting frozen as you tighten the bolt, you need to lengthen the post. So either get a new post or use enough washers (or a thicker washer) to effectively lengthen the post.