bryroth

I have an 05 Kona Jake that I upgraded to a 9 speed. I started off last year knowing absolutely nothing about my bike. Now I am fairly confident in doing most of the basic maintenance and tweaking necessary for my bike, like tuning it up or replacing parts or cables.

However, I am officially sick of messing around with my cantilever brakes. It must truly be an art to quickly adjust these things and still have some kind of braking power. I know that they are more powerful than calipers, give you mud clearance and are generally the perfect and traditional brake to have on a cyclocross bike. I'm still tired of it.

Is it possible to put disc brakes on this bike instead? If so, how much would you charge to do this?

Thanks for any help, and apologies if this is an impossible question or if it gets asked every day here.

Mr. Underbridge

First things first - before you try major surgery, get better pads and see if that helps. Kool-stop pads are a good start. I have cantis on one of my bikes and that made a big difference.

To answer your question, you can't convert the canti bosses to disc brakes. That's not possible. However, some forks/frames have disc brake attacment points. From looking at the 2005 Jake, it doesn't look like it.

However, if you got a new fork that does have disc tabs, you could at least go disc on the front (which is more important anyway). That would leave you still messing with the cantis on the rear.

With the expense involved, it might not be worth it I think you'd do better to sell the Jake and get a cross-style bike that has disc brakes, of which there are decent number these days. The Jake is a well-liked bike, so finding a new home shouldn't be hard if you choose to go that route.

bryroth

Thank you for the response!

Here is my deal: I've got Kool Stops on the front and back, and I've actually spent a considerable amount of time messing with the brakes. There's something about them I just don't like/don't understand. And despite the above, I love this bike way too much to ever sell it.

I like the idea of getting a disc just for the front. Sounds like you're saying if I get a new fork (which I was thinking of anyway) and a new wheel, then it is possible?

dabac

First question is: does it have the tabs? If you take a look at pretty much any suspension fork these days you'll see a tab facing backwards down by the drop out on one of the fork legs. Do your bike have one of those? Do your bike have one of those on the left side by the rear drop out as well?

If it hasn't - well, forks can be replaced, and there are some disc brake adapters for the rear available. It'll up the price though, and make things more fiddly.

Then the next bit is wheels. Some wheels came disc-brake ready, althought they didn't have the rotors installed. If your front hub is identical at both sides, then it isn't disc-brake compatible. And if your front isn't then the odds are really b ad that your rear would be.

Disc brake wheels are of course available too, at a cost.

Then it's down to brake levers, but assuming you're OK with mech discs there are models available regardless of brake lever design.

Bottom line is that a conversion is usually possible, but unless some basic criteria are fulfilled it's probably better economy to buy a used bike set up the way you want it already from the beginning.

rhenning

You know you can just bolt on V brakes/linear pull brakes. Those are better/easier to adjust than cantilevers. You will also need to use different brake levers and/or an adapter called a Travel Agent. Roger

bryroth

I'm worried about two things: 1) I'll never sell my bike for near what I put into it and 2) a new cx bike will be thousands of dollars unless I get lucky on craigslist.

But it sounds like I can put a front disc on it fairly easily by doing the following:

* Buy a new fork
* Buy a new wheel with rotor

As for the brake levers, I use Shimano Ultegra right now. Is this apples and oranges or can I use STI levers to manipulate disc brakes?

cyccommute 

First, go here to learn how to adjust cantilevers. No real art involved but they are a little harder to adjust than other kinds of brakes. Properly adjusted they are just as powerful as any kind of brake out there.

As for changing over to disks for the Jake, I'm don't think you can do it without a whole lot of head ache and money. None of the Kona cross bikes seem to have disc tabs on the frame so you can't mount the disks there. You could change out the fork as Mr. Underbridge suggests but the cost of the conversion could be very prohibitive. You'll need, at a minimum, a new wheel, a disk caliper and a fork. Probably from $200 to $350 in parts. If you don't do the job yourself, you are probably looking at another $100 to $150 in labor. On a $900 bike, $500 in upgrades is probably too much to invest. Better to save it and look for a new bike...or learn how to adjust the cantis

dabac

You can use STI, if you get the Avid mech brake with the road lever actuation ratio.

bryroth

This one:

https://planocycling.com/itemdetails.cfm?ID=9611

dabac

That's right.

But what kind of cantis are you running right now, threaded post or smooth post?

The ones with smooth brake pad posts could be a PITA to align properly, but there are cantis that take threaded posts as well, and they set up just as easy as any of the v-brake designs out there. Going that route would probably require the least amount of changes to your bike.

bryroth

I'm using threaded. They are Avid Shorty 4. My problem is that one side travels faster than the other side, and I'm tired of the squeal associated with it. I've got them toed in properly and all that. It just took me a while to notice that while the left side moves like half an inch before it touches the wheel, the right side only needs to move like a quarter of an inch. I know what you are thinking- that I need to adjust the distance. Well, you'll just have to take my word for it that the cable pulls one side faster and farther than the other side. It is almost impossible to get them to touch at the exact time, and when they do, it is because I have them spaced so that the left side is almost already touching the tire, and the right side is like a half inch away. If that makes any sense.

Also, when they are set up the way that I like them they are almost too tight for me to remove my front wheel, which I need to do twice a day at least.

Like I said, there is something that I just don't like about them, and it isn't for lack of effort. Or maybe I'm just wishful thinking that there are some brakes out there that you only have to mess with once a month at most.

LarDasse74

It's a pretty big operation - you are going to have to change your fork, your frame (or have it modified which is probably more expensive), your wheels, and your brakes. You are probably looking at close to $600 to do the whole job, and even then it might be hard to source all the parts you need - there was someone on here a few weeks ago who was planning on buying a Nashbar (I think) CX frame and found that even though the frame has disk tabs, it would not properly fit any commonly available disk hubs.

Changing the fork and front wheel/brake is easier, but even then I am curious how badly your cantis work that would make even that modest (by comparison) investment worthwhile. My touring bike is my primary ride (for off road, commuting, longer road rides) and I find the cantis acceptable, and once they are set they stay set until the pads wear out or I dent my rim. They still squeal when it is wet out, but I don't mind that too much.

Second thought ...

Buy something like this...

https://www.bikesdirect.com/products/motobecane/outlaw.htm

and strip all the parts you need then sell what is left from the two bikes.

bryroth

^^^
Very cool idea.

I appreciate everyone's responses, it has been a big help.

I'm going to be a little difficult to please I think because as much as you are making sense I think I want to do this anyway just as a project. I'm interested in turning my bike into a frankenstein. If I am going to buy a new bike, I'll buy a nice new road bike, but my current bike will always be a mongoloid- I like messing with it.

So if I were to do this cheaply I found the following pieces:

Fork: $50
Rotor: $40

Now I'm just having some trouble finding a 700c or 29 inch tire to put up front. If I find one for $50, then the project should only cost me about $150 plus labor, yes? So I can live with that I think.

dabac

I'd say that those are separate issues.

That's often, but not always the cause. Sometimes it's down to some pad/brake surface issue (I've got a pair a of ceramic rims one of which squealed like crazy until it got broken in.)
If you haven't tried I'd suggest giving the rims a thorough clean and the pads a light sanding.
I've also had a pair of Tektro V-brakes that just couldn't be quieted down. My suspicion is that those had way too much slop in the pivot bearing.

This sounds weird. It's quite common not to have the pads reach the rims quite simultaneously, which is fixed by adjusting the tension of the return springs. There may be an adjustment screw on each brake arm, or just on one. If the return spring adjustment is bottomed out there is usually a way to move the anchor point of the return spring for coarse adjustment first.
If that's not your issue, then something is out of alignment. The rim really should be sitting smack in the middle between the brake bosses - at least I've never come across an exception to that rule. What happens if you flip the wheel around? will the problem move to the other side or will it stay put? If you can get the short distance to move by flipping the wheel over then either your frame/fork is assymmetric, or your wheel has the wrong dish.

Are you using a separate straddle cable or one of those thingie that branch off your main brake cable? Quite a few people are happier using separate straddle cables.
Are you perhaps using some off-center cable hanger that causes the brake to have lopsided pull?

If it's about touching simultaneously, then I'd say it's a return spring issue. If it's about taking bite simultaneously I'd say there's something lopsided in your cable, either in pull direction or in the yoke cable.

Which of course you're entirely entitled to do. But generally speaking they tend to get good reviews.

This also have me thinking about yoke/transverse cable issues.

For the ultimate in low maintenance brakes, go for drums. But discs tends to be fairly robust too. Apart from that it's all down to ride distances and characteristics, but I can't recall last winter's commute causing any significant amount of brake work (avid single digit).

bryroth

Hey dabac, thanks for the long reply. You definitely get my problem, which is very cool. It is my transverse cable, which is what drove me crazy.

For the record, I noticed all this after cleaning my rims, sanding the pads and using a matchbook to toe them in. The threaded pads are both set up the same distance and everything is as tight as it will go.

So:

I've been thinking the same thing as well, as I can wiggle them with my hand even when they are tightened down. One of the reason I want to take them off.


There is one on each. Unfortunately, this is not the issue.


Very good idea, but it does not move. Dish must be correct.

I'm using one of those thingies. THIS IS THE PROBLEM. However, I don't really see a solution for it. It's working as designed, I suppose. There's just not much to it.

Yes.

bryroth

Found one:

https://www.wiggle.co.uk/p/Cycle/7/Sh...el/5360021823/

So that brings the project cost for converting the front brake to a disc brake to $170 plus labor.

wrk101

I suggest you take the bike to your favorite dealer, and pay them to adjust the current brakes. It won't cost much, probably $10 to $20. Certainly cheaper than undertaking extensive modifications of your bike.

You could also possibly find a good mechanic through Craigs List, and watch and learn from them when you have them do the adjustment.

Sometimes, there is a certain amount of finesse needed to make critical adjustments. So someone that does it full time can make a quick ten minute adjustment to solve your problem.

Mr. Underbridge

Based on that, you don't have the canti return spring balanced properly, which causes the exact symptoms you're describing with one arm having tension and the other not. Knowing how to adjust that is key to getting cantis right. Dabac is right, those springs can be adjusted to get both pads hitting the rim at the same time.

It's also not the link cable. I have one on my cantis, and it doesn't screw things up. If it really is lopsided to the point that the tension screws can't fix things, then you just need to change the position on the main cable where the link cable attaches. Not a big deal.

With cantis, the arm that doesn't get the main cable generally has a hook instead of a pinch bolt that you can use as a quick release. You slide the cable out from under the hook, which lets the arm lay flat. They're designed this way so you can get the wheel off. In fact, if you can get the wheel off at all without using the quick release, then your cantis are probably way too loose.

I'm thinking you just need to learn a little more about tuning cantis. Believe me, before I learned how they work I had the same list of complaints as you - can't get the things to have decent stopping power without one of the shoes rubbing, constantly adjusting, pain in the ass to get the wheel out, etc. Now that I've better learned how to adjust them, I don't have those problems.

Put simply, I guarantee your problems with cantis can be solved. If they were flaws inherent in cantis, no one would use them. For what it's worth, I haven't adjusted my cantis in months.

I'm not saying don't go for discs, because they have their place. I have an MTB with discs. But the problems you're having can be solved with a little more knowledge about cantis. Try these:

https://bicycletutor.com/adjust-cantilever-brakes/
https://www.parktool.com/repair/readhowto.asp?id=19

Also, if you're thinking that by switching to discs, you'll have a system that is inherently simpler and require less maintenance, I don't think you'll find what you're looking for. Cantis are dead simple when you know how to use them. If you just don't want to get to that point (which is fine), V-brakes will still solve your problem for cheaper, since you'll just need the brakes and a part that switches the brake actuation ratio for you.

bryroth

^^^
All good points, thanks. It sounds like I was wrong about what the problem is.

Also, I explained badly about not being able to get the front tire out. My problem is that the pads are so close to the rim to begin with that I can't "unlock" the brake arms to let the tire out unless I really mash the suckers down on the rim.

Is the "return spring" the same deal that you adjust with the very small allen wrench?

Thanks again for all of the above advice.

Mr. Underbridge

Ah. Nevermind. Yep, that's pretty close indeed!

Sure is. By playing with that guy, you should be able to nail the adjustment.

If you can't, I forgot to add one possibility - when you take the canti arms off, there's a spring in there (the return spring you're adjusting, actually), and the Allen screw sort of serves as the fine adjustment for that. For coarse adjustment, there are usually three holes on the canti boss that the spring arm goes into. By changing which hole the spring arm goes into, you end up with more or less tension to start from.

Now, it goes without saying that both arms should start with the same basic amount of tension, which you fine-tune with the Allen wrench. It could be that whoever built your bike didn't use the same spring position for the two arms, creating an imbalance in pull that might overwhelm what you can fix with the Allen screw adjusters.

Here's a diagnostic question - you say you have Allen screws on both arms - to get it balanced as best you could, do you have one screw all the way in, and the other all the way out? That would be a sign that there's a tension mismatch. Either that or the link cable was set at the wrong position, possibly? One of the two, I'd think. If that's the case, then the brakes were installed incorrectly.

Good luck. If you want to give it a try before you dump the cantis, I'm sure folks on here will get you there. If you have the time, it might be worth uninstalling the cantis and re-installing them correctly. That way, you'll definitely learn how they work, and once you do you'll get them right. And if that doesn't work...well, you were going to yank them off anyway, right?