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First attempt at a bike tuneup. Day 2. I just replaced the front brake pads and finally got them with enough space so there is no rub on the rim. Now I squeeze the right brake lever and it applies the brake properly but I have to pull it all the way to the bike handle (pic1). So the brakes do work but I though I should leave space between handle and lever when brake is applied.

So, here is what I have tried: Adjusting the V brake cable (pic2) - however, if I tighten this the brakes will rub against the rim. I also tweaked the brake adjuster near the brake lever (pic3) but this does the same and creates rim rub. Also note that both of these methods do not appear to resolve the slack.

Grateful for any help!

pic1 pic2 pic3 pic4 pic5

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  • Isn't that the left hand lever, for the front brake? Looks like the left lever in the pic. (Yes, I realize you might be in the UK.) Apr 8, 2018 at 12:07
  • Is the rim true? That is, completely flat in the vertical plane? If the rim has distortions it will take up more space between the brake pads. You should be able to spin the wheel hard while its off the ground, and the rim should not wobble any more than a millimetre, ideally less. If there's more wobble than that you need to true it.
    – Criggie
    Apr 8, 2018 at 20:10
  • Could you just zoom out the 2nd picture. There's something strange there. Please place your camera on the front wheel facing the front end of the bike so that we can see both arms of the brake and that part of the cable connected to the brake.
    – Carel
    Apr 8, 2018 at 20:10
  • ArgentiApparatus -- You are correct it is the left hand lever not the right (sorry!)
    – Tim
    Apr 9, 2018 at 9:44
  • Criggie - no wiggles - the rim spins true.
    – Tim
    Apr 9, 2018 at 9:44

1 Answer 1

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You are correct that there should be some space between the lever and handlebar when the brakes are fully applied.

I think I can assume that you have set up the calipers so that the pads are the correct distance from the wheel rim - a few millimeters (or a bit more if your wheels are a little out of true), as you say that adjusting the cable causes the pads to rub on the rim.

If the lever hits the handlebar there must be excess slack in the cable somewhere.

You say that adjusting the cable at the caliper or using the barrel adjuster does not improve the lever travel. If you pull the lever, does the caliper move immediately, or if there cable slack being taken up before the caliper moves?

I'm guessing that something is binding in the cable run somewhere causing the caliper arms to retract to a certain point, but there is still slack cable between the caliper and lever.

You can check the cable run between the lever and caliper, ensure the housing is properly seated, unhook the caliper and check the cable runs smoothly in the housing. Apply tension to the cable by gripping it with some pliers and check the lever pulls it immediately.

You could also choose to replace the cable and housing, which is a common thing to do when tuning up a bike.

You can check if you have set the brakes up properly be checking out some online resources. Park Tool Company has some great brake adjustment videos on their YouTube channel. Here is the V-brake video.

Update based on new info in comments:

The problem seems to be: one caliper arm is retracting less that the other and then rubs on the rim. You then find you need to slacken off the cable to stop that non-retracted arm from rubbing.

The solution is, of course, to fix the non retracting caliper arm. It's a common problem for the V-brake arms to get sticky and not retract symmetrically.

  • Remove the caliper arms, clean the arm bushings, posts and springs, re-grease and reassemble.

  • Adjust the spring tension screws on the caliper arms so that the arms retract symmetrically (see picture below).

enter image description here

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  • Thanks for the response. If I pull the lever the caliper moves immediately and throughout me pulling on the lever. I'm going to try what you suggested and see if I can find where the slack is. I will follow up.
    – Tim
    Apr 9, 2018 at 10:16
  • If there is a lot of lever movement after the pads touch the rim, something is flexing excessively. Apr 9, 2018 at 11:13
  • So I've been tweaking around with it. I pulled the cable tighter so there is less slack. It leaves roughly a finger-length in between lever and handle. I spin the front tire and it spins without rub. I squeeze the brake and it stops correctly. But when I release the brake it's almost like it moves the caliper out of alignment and on subsequent spins the brake rubs against the rim. Okay, now I loosen the cable, spins correctly even after applying brake.But we are back to original issue, the lever goes all the way to handlebar.
    – Tim
    Apr 9, 2018 at 13:12
  • I added pic5. Could this missing screw affect the brake tension in the lever?
    – Tim
    Apr 9, 2018 at 14:47
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    It looks as if there's a lot of slack in the cable. But there is one thing I'd check with the cable unhooked: is each brake arm moving freely and if you push it against the rim does it spring back when you release it. If not The pivots need cleaning and greasing and/or the springs are 'tired'. And since cables and housings are not that expensive replacing those may be a good idea.
    – Carel
    Apr 9, 2018 at 16:14

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