One calliper arm seemingly not long enough!?

holiver

Hi guys,

I am having a Kinesis Racelight T2 built up at present. It is sat in the shop complete apart from a cable routing issue and this strange problem the shop and I have noticed with the rear brake calliper. Basically the right calliper arm doesn't seem to be long enough for the pad to contact the rim completely. It is sat too high and will contact the tyre after a bit of wear which obviously isn't safe!

The brakes are a set of Miche Performance 57mm drop callipers, which are frightfully cheap at Halfords:

http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_929715_langId_-1_categoryId_273957#tab3

The frame specifies 57mm drop brakes:

http://www.kinesisbikes.co.uk/products/racelight/t2

The wheels were purchased from a forum member here and are a few year old Campagnolo Khamsins, with some 23mm Continental Gator Hardskin tyres upon them.

Does anyone have any idea of how to fix this? The shop are recommending filing away at the calliper arm a bit to allow the pad to drop down some more, but I am not sure this is the right approach with something as important as brakes. I may have to return them and purchase some new ones...

Your thoughts and insight is most welcome!

Thank you.

halfround

Could try some different pads the fittings on some allow a lower position , but it is small. I would be happy to file the arm if it is just cleaning up the casting and have done so to solve this problem .

hugo15

Hmmm..... I have a Tk3 frame fitted with Tektro deep drop brakes. When cleaning the bike last week I noticed last that on the rear brake the pad on the drive side of the bike is very close to the tyre. Sounds very similar to the OP issue but with a different Kinesis frame.

holiver

That's interesting regarding the TK3. I'm struggling to think how a frame could affect the position of one brake arm. Could it be that the brake mount isn't quite centered? I was thinking it was a manufacturing defect on the brakes...

I did purchase some aftermarket pads, but the shop and I have tried both these and the original ones. Even the original ones aren't quite there. I think I will have a play once I have the bike at home, but I will probably end up sending them back. I'll inspect the arm, but I think it would need at least a couple of mm taken off which is quite a lot.

Here are the new pads I bought and had fitted:

http://bbbcycling.com/bike-parts/brake-shoes/BBS-22T

desweller

A photo would help.

smidsy

If 1 side fits and the other does not then it sounds like a centering issue to me.

hugo15

I had another look this morning at my TK3. Both of the rear brake pads are contacting the rim very close to the tyre with the shoes right at the bottom of the slot in the calliper, but the drive side one is slightly closer than teh non-drive side.

holiver

Thanks for the further replies.

I should be picking the bike up today so will take some photos then and upload.

hugo15 - which model of Tektro does your TK3 have? Does everything look centered around the wheel?

keef66

I have a Tk with Shimano long drop brakes (BR450's?) and have no such problems. Maybe it's a problem with the Miche caliper. What happens if you swap front and rear calipers? Same issue?

holiver

Hmmm haven't tried that yet. Am about to go to the shop so will try that then.

Thanks for the suggestion!

Yossie

If its just a bit of Dremelling the caliper arm down then cool - go for it, just leave enough metal on there.

holiver

OK I now have the bike back, which will be the focus of a topic in the Your Road Bikes sub forum at some stage soon.

However I have taken a few pictures of the back calliper to illustrate the problem. You can clearly see the right arm is higher than the left.




And when the brake lever is pulled:




The front is not an issue at all - the pads aren't even at the bottom of the calliper arm and there is room for adjustment.

I am miffed. Should I return the brakes? The pads on both sides need to drop down really...

keef66

Seems odd. Is the wheel fully seated in the dropouts? ie have you loosened and retightened the QR with the bike the right way up and the weight of the bike on the wheel?

Maybe you have a duff frame with the brake bridge too high?? I can measure my Tk tonight if you like.

holiver

Yep I have made sure the wheel is fully seated in the drop out. Sure the ride home would have been interesting if not!

I guess the frame being out of whack is a possibility. I wouldn't know where to measure to make sure though. If you were able to it would be good. Although might the frame size have an effect on the measurement?

I've looked at the front brakes again and noticed something strange. Only one of the pads there is seated at the bottom of the arm. One is a bit higher. No idea why this is. Is this normal?

k-dog

Is there a centre adjustment on those brakes?

If so, it looks like that adjustment could be wrong - and the brake has just been twisted to make the gaps even - which isn't the same thing.

You need to remember too that the different arms don't move the same - one goes in and up slightly and the other down slightly (that could explain the front brake setup).

If you don't have a centre adjustment then none of this matters...

k-dog

Fwiw my dad got a bike last year with those brakes and they broke almost instantly. The lever to open it up is plastic and broke inside so they wouldn't stay closed (or open so you couldn't just tighten the cable).

Wiggle sorted it out and sent some Tiagra brakes as they couldn't get the part - much better and well worth the £20.

holiver

I think the below photo shows the centre adjustment?



The manual states this allen bolt is used for centreing the brake with the wheel. I've had a play around with it and think I've improved things slightly, although the pad isn't quite low enough still.

I will have a further play around tomorrow...

Thanks for explaining how the brakes work!

Yeah the lever is plastic, but it seems fairly well made. It may well end up being irrelevant if I return the brakes. Then it will be a choice between some Tektro 737, or Shimano BR450 or 650 as discussed in the below thread.

viewtopic.php?f=40042&t=12932741&hilit=miche#p18446917

k-dog

Yeah, that's what you need. It'll be a bit of trial and error to get them right but should be possible.

smidsy

smidsy wrote:

If 1 side fits and the other does not then it sounds like a centering issue to me.

At the risk of repeating myself

Yossie

k-dog wrote:

Fwiw my dad got a bike last year with those brakes and they broke almost instantly. The lever to open it up is plastic and broke inside so they wouldn't stay closed (or open so you couldn't just tighten the cable).

Wiggle sorted it out and sent some Tiagra brakes as they couldn't get the part - much better and well worth the £20.

That's nice of you to let him know - bet he's glad he knows that now that he's got his new bike and you're slagging bits of it off. Cheers mate, just what you need on a sunny morning.

Yossie

holiver wrote:

I think the below photo shows the centre adjustment?



The manual states this allen bolt is used for centreing the brake with the wheel. I've had a play around with it and think I've improved things slightly, although the pad isn't quite low enough still.

I will have a further play around tomorrow...

Thanks for explaining how the brakes work!

Yeah the lever is plastic, but it seems fairly well made. It may well end up being irrelevant if I return the brakes. Then it will be a choice between some Tektro 737, or Shimano BR450 or 650 as discussed in the below thread.

viewtopic.php?f=40042&t=12932741&hilit=miche#p18446917

Yup[ - that's your baby.

As an aside, why didn't the shop know this? All brakes have these so they should have been able to have a play and sort it.

I think that I have ordered some of these brakes for the "winter bike that gets lent to people I know will trash anything good" so will report as well on centering issues. Are these the £16 or so ones?

holiver

I think the shop thought they had got it as centered as possible. I may have only improved things a very small amount.

Went out for a quick 30k ride last night and the front brake does a good job. They may be for sale soon if Halfords won't accept a return if I can't get things sorted fully!

I think I may need new brakes. Looking back at the thread I started where I requested suggestions for long drop brakes, the Tektros I mentioned seem to go down to 59mm drop. Those may be the best option, as I am not sure if the Shimano models go as deep...

viewtopic.php?f=40042&t=12932741&hilit=miche

Any idea whether there's much difference between the R539 and R737 Tektro models?

http://tektro.com/_english/01_products/ ... rt=1&fid=2
http://tektro.com/_english/01_products/ ... rt=1&fid=2

Yossie

I've used loads of Tektros before (and am currently running their carbon ones of the fast commuter/summer trainer) - no problems at all over 2 years, still look good, work as good as D/A and Record, lighter, better looking and cheaper than the shoddy junk that is Ultegra.

hugo15

holiver wrote:

hugo15 - which model of Tektro does your TK3 have? Does everything look centered around the wheel?

It's got Tektro R539 brakes. Everything looks centred too. Both of my pads contact the rim very close to the tyre. I don't believe it's catching the tyre but there is one 1 or 2 millimetres in it. I'm tempted to take a file to the slot in thr calliper just to make sure.

holiver

OK cool, thanks for the follow up!

I have been fiddling around with the position of the calliper on the frame and the centre adjustment, and have made a bit of progress. Still not quite right, but I may break out the file too as the measurements involved are now pretty small.

holiver

I emailed Kinesis to get their view on the brakes. Here's their reply:

We have found that these cheaper Miche brakes simply do not have enough drop tolerance, 57mm is just not quite enough, whereas our Tektro long drop 59mm drop brakes are spot on. There is not much more I can suggest I’m afraid, the Miche brakes are not compatible.

Wish they'd put 59mm on the website!