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So I have this second hand Canondale lefty MTB which I love very much. Rode it around home in the woods, but now I visit more and more events and I need to transport my bike by car to the event. Unfortunately I have to remove the front wheel of the lefty and with that the brake caliper. And the biggest problem is putting the bike together again without the caliper screeching against the disc.

For clarity, I remove the two bolts and then the whole black part on the right in the picture below. I think that's the brake calliper.

enter image description here

What is the trick?

I've watched some video's on GCN, asked my friends (who don't have a lefty), read forum posts, but no failsafe solution. It takes me sometimes almost an hour and three times removing the wheel again before it finally fits perfectly. Surely there is an easier way....

Please help.

  • Removing the front wheel of the lefty regularly is fighting against one of its fundamental design principles. It might be a lot more convenient to carry the bike on a rack that allows front wheel to stay on - rood rack, tow hitch or strap are all suitable options. – mattnz Oct 25 '18 at 23:31
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With most of them the trick is you only unfasten the adapter to get the wheel off, not the caliper itself. The adapter doesn't have any range of adjustment in how it mounts to the fork, so it can be removed and re-installed without disrupting the adjustment.

There may be a post mount only Lefty out there. If so, the difficulty you're having is basically unavoidable.

It's also important to get a pad spacer in there when the wheel is off.

Edit in reply to comment:

So, you have the XTR brakes, I believe BR-M975, that represent one of very few disc brakes ever made that connect directly to IS tabs without any kind of adapter. There aren't many brakes like this and dealing with this design involves some steps that won't be covered in generic instructions about adjusting disc brakes. This design can only be adjusted for alignment by adding and taking away micro shims between the caliper and the fork. It's a little cruel and unusual that you wound up with the combination of this brake on a Lefty, because it creates hoops to jump through that would be troublesome for anyone. The good news is that once you get the shim configuration figured out that results in good alignment, you can keep the shims there on the bolts while the wheel is off and it shouldn't require readjustment when you put the wheel back on.

Such shims can be ordered online or bought from any good shop. There are two types; one (Shimano) is open and has two prongs, the other is like a really thin (0.1mm) washer. You want the washer type because the other one will want to fall off whenever you go to remove the wheel. With the washer type, just screw the caliper mounting bolts back in to the fork a few turns once the wheel is off, down to the loctite.

The goal of the design is that with fresh pads, properly faced tabs, and everything to spec as per the IS standard, the caliper can be bolted to the frame and everything is perfectly aligned without any adjustment at all. This may or may not be achievable on any given fork or hub, depending on exact adherence to the IS spec in terms of lateral position of the IS tabs and the rotor mounting surface on the hub.

  • Maybe I'm not using the correct words. As you see in this picture: link I remove the two bolts and then the whole black part on the right. I thought that was called the brake calliper. Or is that called the brake adapter???? – Gabrie Oct 25 '18 at 22:51
  • Edited in response to pic. – Nathan Knutson Oct 26 '18 at 0:18
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I know when I have purchased new prebled calipers they came with a plastic shim. the shim fits between the pads. If the brake handle is accidently squeezed the shim acts as a rotor would and prevents damage. In lieu of the factory shim I think thin piece of wood or plastic slightly thinner than the rotor would work. The factory shims contain clips that hold them in place. I think zip ties or rubber bands would work as well.

  • Hi, I've use this one: link but no succes. – Gabrie Oct 25 '18 at 21:47
  • Do you use it as an alignment tool to reinstall the caliper or as a spacer to keep the pads from closing? – mikes Oct 25 '18 at 21:55
  • I don't know :-) I first use my screwdriver to open the brake pads. Then I put the alignment tool on the disk and then put the brake calliper over the alignment tool and screw it LIGHTLY to the fork. When it is lightly attached, I then squeze the brake handle a few times, hold the brake handle squeezed and then tighten the calliper screws. – Gabrie Oct 25 '18 at 22:04
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    What I am suggesting is removing the wheel with out moving the caliper, stuffing the shim between the pads.When you get to your destination remove the shim and reinstall the wheel. – mikes Oct 25 '18 at 22:20
  • See the pictures: link and link I don't see other ways to remove the wheel then to unscrew those two big bolts. – Gabrie Oct 25 '18 at 22:41

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