Decided to take the advice of the forum and ditch the (frankly dangerous) cantilevers on the CX bike in move to mini Vs, which were kindly provided by Northwind of this parish.
I have however stumbled across a fundamental flaw in the fork design when fitting them...fork is this [url= http://www.dolan-bikes.com/index.php/dolan-cyclo-cross/cyclocross-framesets/dolan-multicross-aluminium-cyclo-cross-frameset.html ]dolan fork[/url]
Basically the 'bulgy bit' on the fork by the cantilever stud catches on the back of the vbrake when you've tightened it up fully. The obvious solution was to put in a couple of mm of spacers to move the vbrake away from the fork, but it was pointed out that this means that i'd need to lenghten the stud as well, which I can't do.
So basically I'm left with a bike that will only take the worst type of brake available to man....
new fork time 🙁 Or ingenious fudge?
Cantis are better than red22 hydros at the moment in this weather!
Based on my cantis and being unsure how they mount to the studs (although park tool confirms what I think), longer centre bolt to hold onto the stud? That is a bodge as much as I can think, can't think how else it could be bodged on I am afraid.
Can't see from that pic, are the studs removable?
Most are, and there are many different lengths available. Also two common diameter, 8 and 10mm so don't just pick any old pair. Head down your LBS and ask to have a rummage in the spares box. Longest I've ever seen were from some old RST HI5 forks, sold mine on ebay for about the same as I sold the rest of the forks for (£20ish, they were awful forks!)
I've amended my post as it made zero sense! But the issues is the same.
Maximus, the problem is that you normally tighten the bolt against the end of the stud, which you can't do if the vbrake extend past the end of it.
Just checked and they are indeed removable, great shout Andrew H.
So now I just need longer studs and some washers...hopefully
or small dia washers inside the mini v arm but over the longer bolt? or as ah said, dont bodge and change the stud.
haven't seen that fork in the flesh but have had this with other cx forks and my guess would be:
basically cheap mini vs have the pad behind the arm which catches on some cross forks. Doesnt seem to be an issue on the back of most frames.
posh cx mini vs (and normal cantis) have the pad mounted further forward 'in' the arm e.g trp cx 8.4s and don't catch. why this is the case i don't know but its a bitch and you have to either spend ££ on new forks or posh brakes.
Get decent cantis and set them up properly?
For your FYI, v brakes usually don't pivot on the stud, they have an internal bushing. So it may have worked (not tried it though)
My cantis were set up by me first, then the lbs, tried bedding them in, tried new blocks, neither of us had any joy.
the new longer stud wont work I don't think, as the spring pin still needs to engage the wee hole, which rules out my spacer option...
As a very drastic option, could I saw/grind off the offending part on the vbrake, ie along this red line. The Block would still be secure, but would it weaken the brake?
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if you cut that off, it will weaken it, but my guess is you won't be to bad for the performance, and should still be strong enough
I will add a decently set up pair of cantis will be as good a a set of mini vs and have better mud clearance, also when flexing is causing the bad breaking a break booster can help
I will add a decently set up pair of cantis will be as good a a set of mini vs and have better mud clearance, also when flexing is causing the bad breaking a break booster can help
Would you really want to take advice from someone who doesn't know the difference between break and brake? 🙄
Would you really want to take advice from someone who doesn't know the difference between break and brake?
Come on it's an easy mistake to make, give the man a brake 😉
Don't cut it whatever you do.
Don't bodge brakes, it will end worse than if you carried on riding cantilevers.
New forks is your best option, and at which point you might as well have gone disc on the front.
I think alot of the complaints about canti's on cross bikes is due to over expectation, or cheap hard brake pads.
Definetly would not cut the mount above not worth the risk of failure.
I think you have 3 options:
1. See if there is a alternative V brake that may fit.
2. find some better cantis than what you had previously and fit them.
3. Use a different fork if the latter you may as well go disk.
Have you tried dropping Dolan a email too see if they have had this issue before and can recommend any alternative brakes that will fit.
Thanks all for the responses so far. So cutting definitely out.
I've found if I unscrew the brake stud by a couple of mm it fixes the issue by moving the brake further from the fork. Trouble is that leaves the stud only half way in the fork thread, and more importantly loose.
So if I can get a brake bosses with a longer thread it would be sorted. Can't find one on the web however.
I'd happily buy a fork in the new year, but as I was planning to do some riding before then I was hoping a quicker fix was at hand. Clearly not 🙁
more like a phones autocorrect that doesn't know the difference between break and brake 😕
If you end up getting a new fork Planet X are knocking out the carbon Uncle John forks for £50 at the moment, and i can report that mini v's work just fine on them.
OP did you read my post?
Better quality vee brakes (all Shimanos I am aware of and some Tekros) have the internal bushing which means the securing bolt can be tight against the end of the pivot. Cheaper brakes pivot on the stud itself so need the securing bolt to be tight on the stud but have a small clearance on the brake to allow it to move, ie the stud is slightly longer than the hole through the brake.
Mini vees are designed to have the same pull ratio as cantilevers to avoid the excess lever travel full length vees would give with drop bar levers, hence they should work no better or worse than cantis.
If the cantis aren't working well then I'd suggest there's something wrong with the set-up, eg dry or sticky pivots, over flexible mounts, cables in poor condition, straddle wires not correctly angled?
[url= http://www.paulcomp.com/motolite.html ]Expensive but should work.[/url]
Or go back to better canti's with some Kool Stop Salmon pads.
Cantis on cx bikes are great when set up properly ...for the first 5 minutes, after which they are garbage.
Full-size v-brakes (with suitable levers) are far, far better.
The shimano mini-v brakes are a slightly different style. Struggled to find a better/bigger side-on picture, sorry.
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Thanks for the replys folks
Al, The mini Vs don't have an internal bushing I'm afraid.
Those shimano Cantis look like the solution, and available in Evans for 13 quid! Job done
🙂