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Old 12-04-10, 09:43 PM   #1
Merzperson
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Cable Routing Problem



I have a Bruce Gordon BLT that has an odd problem. The front brake cable runs down between the two shifter cables (see photo). When I steer more than ~30 degrees in either direction the brake cable hits one of the shifter cables. As I continue to turn the bars the front brake will tighten, stopping the front wheel. The first time I rode this bike I crashed because I was turning around a gate and my front wheel stopped.

Luckily there isn't any serious danger as you will never turn the bars more than 30 degrees while riding fast, but it is still pretty annoying. It also means I have to keep the bars straight when I am packing the bike into my car (small Civic hatchback) which is another inconvenience.

Does anyone have an idea? I have thought about switching to a front v-brake, but then I'd have to buy a new lever and I'd rather not spend that much money.
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Old 12-04-10, 09:54 PM   #2
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What an odd design problem. The only solution I can think of is either purchasing or fabricating a cable stop that attaches to the fork crown rather than the stem or upper fork section. I have seen these in use, but the seem a bit obscure. Also, I am not aware of any drawbacks that this set-up would have. Good luck!

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Old 12-04-10, 10:10 PM   #3
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Interesting idea. That would certainly work, although I don't have the resources to fabricate one. I'll look into buying one. Thank you for your suggestion!

If anyone else has another idea please share.
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Old 12-04-10, 10:15 PM   #4
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Is this what you were talking about? http://www.amazon.com/exec/obidos/AS...osim/neoset-20
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Old 12-04-10, 10:34 PM   #5
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Does anyone have an idea? I have thought about switching to a front v-brake, but then I'd have to buy a new lever and I'd rather not spend that much money.
How about installing a clamp-on downtube cable stop like they did in the old days? That would allow the shift cables to move when you steer sharply. It'd be kind of a kludge, and you'd lose the adjusters on the frame, but no reason why it wouldn't work. They're available from various sources, including Rivendell: http://www.rivbike.com/products/show...e-stops/51-020

It's a shame- have you asked BG this problem?
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Old 12-04-10, 10:41 PM   #6
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The crown mounted hanger will certainly solve the problem. But I'm not I understand why it's an issue. As you point out you never turn the bars nearly that far when riding more than 1mph, so there's no real riding problem. As for packing it in the car, don't you have to remove the front wheel first, and doesn't that require disconnecting the yoke cable to open the brake wider to clear the tire?
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Old 12-04-10, 10:47 PM   #7
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That's also a good solution, but it would be a bit ugly with those braze-ons just sitting there on the headtube. I'm thinking about giving the fork cable hanger a try as Iverhagen suggested, looks like that would solve the problem (but also looks a bit cheap and sloppy).

I have not spoken with BG about this problem, although I probably should. I heard a rumor he was thinking about quitting the business...
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Old 12-04-10, 10:52 PM   #8
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I have not spoken with BG about this problem, although I probably should. I heard a rumor he was thinking about quitting the business...
Bruce has been "thinking about quitting the business" about as long as I've known him, or at least a couple of decades.

Look around, there are some well made crown mounted cable hangers. ot you might look for a hanger with a quick release, like what was used on centerpull brakes back in the day.
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Old 12-04-10, 10:57 PM   #9
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My solution would be to get rid of the front cantilever brake and use an appropriate V-brake to match your brake levers. I run a mini-V on my current cyclocross bike (with campy ergo levers) and like it better than cantilevers.
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Old 12-04-10, 11:11 PM   #10
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Besides the Tektro, there is also the Specialized Tricross Fork Brake hanger:
http://www.specialized.com/us/en/bc/...jsp?spid=57980

I have a Tektro I plan to install shortly.
I currently have a brake hanger mounted just under the stem.
When I switched to KoolStop brake pads recently, I got a nasty surprise when descending grades of 9% or more:
A front brake that would try to lockup every time I touched it.
After much searching, I learned the cause was due to flexing in the fork/steerer that would pull on the cable as it flexed.
I've put the old Shimano pads back on the front until I get the crown-mounted hanger installed.
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Old 12-05-10, 09:11 AM   #11
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+1 for the Specialized hanger, it works great for me. Besides giving you an additional barrel adjuster it includes hardware for both alloy and carbon fiber fork crowns. From the catalog photo I'd be concerned about the Tektro hanger not holding the cable housing securely in place.
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Old 12-05-10, 09:12 AM   #12
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I think your shift cables and housing are too short. Longer cables wont pull as tight when the bars are turned and won't compress the front brake wire. The cables and housing should be long enough that you can turn the bars all the way until they hit the frame in both directions without the cables getting completely tight.
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Old 12-05-10, 09:21 AM   #13
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seems odd to me...
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Old 12-05-10, 11:01 AM   #14
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I think your shift cables and housing are too short. Longer cables wont pull as tight when the bars are turned and won't compress the front brake wire. The cables and housing should be long enough that you can turn the bars all the way until they hit the frame in both directions without the cables getting completely tight.
I think you're missing his problem. BG moved the fulcrums all the way forward to avoid having floppy cables mar his museum quality paint job. The fulcrums are so far forward that when the wheel is turned far enough the Brake wire hits the rigid adjusters, not the flexible housing, which it could push out of the way.

It's a classic case of solving a minor problem by creating a bigger one. One thing the OP can try is removing the frame mounted gear cable adjusters to make more room there, and replace them with in-line adjusters higher up on the gear wire.
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Old 12-05-10, 11:09 AM   #15
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One possible solution that no one has mentioned would be to cross your cable routing. Run your rear derailleur cable to the non drive side housing stop and the front to the drive side. This would mean that all the housing would move in the same direction as the brake wire giving you increased turning radius before contact.
Or you can run shift housing all the way up the bars. (I always hated having the housing pop out of the tape like a bone in a compound fracture.)
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Old 12-05-10, 11:20 AM   #16
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Or just use a V-brake. Seriously!
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Old 12-05-10, 11:41 AM   #17
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As cmdr said, crossing the derailleur cables will solve the problem. This is a common fix, especially if you're using 4 mm derailleur housing, and even if you're not running canti's, is a better routing method.

And, keep the canti brake. V-brakes are inferior stoppers, are heavier and have a high fiddle factor, and no good in the mud or ice; but more importantly they won't work with road drop-bar brake/shift levers (Without using a hokey add-on inline cable pull contraption).
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Old 12-05-10, 12:00 PM   #18
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I have figured a solution to this and the previous problem of the OP - having brakes that are very hard to adjust properly without rubbing... the straddle cable is too low.

Having a very low straddle cable gives you massive mechanical advantage - meaning that it takes very little tension on the cable to activate the brake. It takes so little tension on the cable that pressing it against the shifter housing activates the brakes. THis setup provides maximum braking power (often more than you could ever need) but requires more lever pull and can give a kinda mushy lever feel. THe flip side of this is that the opposite applies to the amount of force required from the brakes to pull back the cable, and extra high spring tension is needed to pull the cable back from the lever when the brakes are not applied, as discussed in the OP's other thread.

This is a problem with the vector mechanics of the brake system - the straddle cable is almost completely horizontal but it needs to pull vertically on the brake cable. The problem will be solved very quickly by raising the straddle cable. THere are two ways to do this - (1) flip the spacers around on the brake pads so the thin concave washer is on the inside, or (2) use a longer straddle cable.
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Old 12-05-10, 12:47 PM   #19
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I took another look at the photo and I think that maybe the crown mounted hanger may not be an option after all. Guestimating the relative heights, I think the hanger itself may collide with the GW adjusters making a bad situation vastly worse.

IMO the OPs options may be limited to using shorter hardware on the GW fulcrums and/or getting a QR up on the brake wire hanger. Otherwise, he can simply get in the habit of disconnecting the yoke to release tension when he needs to turn the wheel beyond it's normal travel.

No one mentioned this, but do the brake levers have QRs, if so than he's probably best off leaving bad enough alone, and living with it.
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Old 12-05-10, 01:36 PM   #20
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And, keep the canti brake. V-brakes are inferior stoppers, are heavier and have a high fiddle factor, and no good in the mud or ice; but more importantly they won't work with road drop-bar brake/shift levers (Without using a hokey add-on inline cable pull contraption).
Huh? V-brakes are way easier to set up than cantis and have both more power and better modulation than the model of cantilevers shown in this thread. (in fact, i like my mini-V brake better than even wide-profile cantis). The OP isn't using integrated shifters so he could use standard MTB style long-arm V brakes, with no "hokey" add-on and the appropriate drop bar lever. If one wants to use integrated shifters like the campagnolo 10 speed shifters I use, then he just choses a v-brake with a shorter arm length and doesn't need a hokey travel agent add-on. I find 85mm to be the sweet spot, though with the latest shimano levers you could use the 90 or even 95mm lengths and still be ok. Or you can use a long-arm v-brake and just use the travel agent. It's no more "hokey" than many other parts on a bicycle.

V-brakes eliminate fork chatter issues and have better cable routing that would eliminate the OP's issue on this bike. I don't know why you question their effectiveness in mud or ice since they are basically just a correctly set up cantilever brake (i.e. 90 degree straddle cable) right out of the box with no fiddling needed. There was a reason MTBs evolved from cantilevers to v-brakes. It's only tradition that has kept cantilevers on touring and cyclocross bikes.

Here's a pic of my bike showing that the front brake cable would be to the outside of the shifter cables:
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Old 12-05-10, 01:59 PM   #21
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And, keep the canti brake. V-brakes are inferior stoppers, are heavier and have a high fiddle factor, and no good in the mud or ice; but more importantly they won't work with road drop-bar brake/shift levers (Without using a hokey add-on inline cable pull contraption).
Huh? This makes me wonder if you have ever seen a properly set up V-brake. I would put my setup against ANY cantilever setup you want to bring to a 'stop-off'. I will concede that a Travel Agent takes some small amount of intelligence to set up, but if I can do it, it can not be that hard!

I switched to a front disc brake for longevity sake on my touring bike, not because the V-brake/booster lacked ANY stopping power. I had to go to a 203mm rotor to match the stopping power!
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Old 12-05-10, 02:23 PM   #22
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It's only tradition that has kept cantilevers on touring and cyclocross bikes.
no. it's the lack of compatible brake levers that tourists and cx racers enjoy.
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Old 12-05-10, 02:23 PM   #23
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The main reason why forks shudder and brakes squeal on canti setups is because when the fork flexes under braking. The front end geometry changes enough, that the cable goes slack to release the brake pressure a bit, unflexing the fork and tightening the brakes. This process will repeat itself and show up as fork shudder or brake squeal.
Not so with V-brakes, because there is no cable hanger attached to the fork and therefore the cable won't go slack even if the fork flexes and changes geometry. Not that it won't get either due to a number of other reasons.
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Old 12-05-10, 02:32 PM   #24
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no. it's the lack of compatible brake levers that tourists and cx racers enjoy.
This thread has already covered how to use any lever one wants with any size v-brake.
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Old 12-05-10, 03:06 PM   #25
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This is getting way off topic. As I said in the first post, I'm not interested in buying new brakes or levers regardless of which is better. The whole thing's not that big of a problem because the levers I have (Cane Creek SCR-5) do have quick release and I rarely find myself in a situation where I need to steer more than 30 degrees, but it certainly would be nice to eliminate the problem for those rare times.

I'm going to take the bike into a shop today anyway and I'll see if they have any ideas. Thanks everyone!
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