Changing front V brakes

[Allan Macdonald]

My Kudos is fitted with a front V brake made by ProMax.
I don't like it, I have had ProMax on other bikes and they, like this one squeal when I apply the brakes. Adjustment lasts for a while and so do decent brake pads, but, eventually, they squeal again.
So, I wanted to change them and bought a Shimano Acera front V brake.
Problem is, the pivot post fitted to the bike has a long collar, the Shimano won't slide all the way along the post so I can't use them. I have other bikes with V brakes, and all the pivots are the same as the Kudos, i.e., the collars are too long for the Shimano brakes to fit.
I have searched on line, but I can't find any pivot posts with shorter collars. Do they exist as after market spares, and if so, where from?
Thanks
Allan

 

[flecc]

This link has a number of choices Allan.

And this link further back may have other suppliers included in a variety of items.
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[Allan Macdonald]

Thanks for the links, unfortunately, all the pivots look exactly the same as the ones fitted to my bike.
I have just tried to fit the brakes on again. They don't slide all the way to the end of the pivot and the spring only just slots into the corresponding hole. I can tighten the bolt up and the brake pivots fine, but there is sideways movement which, I am sure will turn into squealing. They don't look very secure! I'll try and get some pics and post them.
Allan

 

[flecc]

When in difficulty with a bike part, St Johns Cycles are usually a good source for information and availability, so worth a ring.

I hit this same problem once on one of my bikes not long ago but solved it by some part swapping, so haven't a definite source of supply.
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[flecc]

Any of these any good, though they all look similar?
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[Allan Macdonald]

Heres a few pics, this was using one of the unused rear pivots but they are the same as the fronts.
As you can see, the spring is not seated properly and the face of the arm does not rest next the frame. There is about a 2mm gap.

Looking into the pivot, the threads start about 4mm inside

Pivot fitted to bike. Collar is about 5mm

and the corresponding shoulder inside the brake is less than 3mm

Allan

 

[Allan Macdonald]

Any of these any good, though they all look similar?
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I think they are a standard size. We have a bike shop nearby, might nip in tomorrow and have a word. The Shimano pivots must have a smaller collar, although I have changed brakes before to Shimano on a Specialized bike I had and they fitted fine.
Allan

 

[flecc]

I saw one online forum where the answer given was that the posts needed cleaning to allow the brake arms to seat right back. I didn't find that explanation too convincing though, having had this Shimano problem myself. I'm afraid Shimano love doing things differently and it often causes problems.
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[Allan Macdonald]

That would mean I would have to clean at least 3mm of metal of the pivot, I don't think thats a convincing explanation either, nor do I have a polish that removes metal.......