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Okay I waited and waited and finally got a new ss WITH rear mechanical disc brake now...figured it has to be better and was so excited to move from V's to discs.
Obviously, I didn't think this through...don't get me wrong, love the bike, but got a lesson today.
Seems that those horizontal dropouts don't let the rear wheel fall freely when you have to remove the back wheel for a flat like verticals do...duh...how did I not realize this??
Now I have to unscrew the rear caliper from the mount to remove the rear wheel!! :madman:
My simplicity has been ruined...:skep:
Did anybody else get this rude awakening or am I the only one who didn't see this coming.:confused:
 

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My Spot is set up w/ horizontal drops and discs. I loosen disc brake's lower caliper bolt and that provides enough "wiggle" room to remove the wheel and keep the caliper in place.
 

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Yup. The same with my IRO Mia!

Yeah, what shiggy said.

Accounts are a bit lacking here about that little caviat with discs and horizontal drops. But the truth is, it's not a big hassle, even when changing flats on the trail.
 

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Here's my setup. The caliper lives in front of the rotor, and once it's been setup for your wheel position (determined by gear sizes and chain length) it never moves when you have to take out the wheel.
 

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how odd that i was only talking to someone about this exact issue this morning

that is a much better way to mount on a horizontal dropout frame. i wonder why surly/on one/etc are still using the seatstay mounting position when they could have the mounts on the chainstay?

what is that frame miles? a custom?
 

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pinkdirt said:
Seems that those horizontal dropouts don't let the rear wheel fall freely when you have to remove the back wheel for a flat like verticals do...duh...how did I not realize this??
This issue is very caliper/frame dependant, the trick is to get the slave pistons positioned at 12:00 or slightly earlier wrt the horizontal mount. With the caliper thus positioned, you can adjust the chain tension without need to adjust the caliper.

Here are a few things to try:

Use a different caliper/system - I know that Magura Louise rear ISO calipers mount much farther forward than the Avid Post mounts.

Use a different ISO to Post mount adapter - Hayes adapters place the caliper further forward than the Avid adapters.

Use a "wave" rotor - the notched in the rotor may give you enough clearance to remove the wheel.

Use a 180 (or larger) rotor, and select a post mount adapters that places the caliper farther forward.

If a combination of the above still does not let you remove the wheel without lossening the caliper mount, and the interference is minimal, you can also shim the rear of the post mount with a washer to tilt the Avid caliper forward and clear the rotor. Slight misalignments of the pad - rotor will have a very minor effect on the brakes.

Simplicity may still be withing reach...

Cheers,

Tom
 

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Wow

itsdoable said:
This issue is very caliper/frame dependant, the trick is to get the slave pistons positioned at 12:00 or slightly earlier wrt the horizontal mount. With the caliper thus positioned, you can adjust the chain tension without need to adjust the caliper.

Here are a few things to try:

Use a different caliper/system - I know that Magura Louise rear ISO calipers mount much farther forward than the Avid Post mounts.

Use a different ISO to Post mount adapter - Hayes adapters place the caliper further forward than the Avid adapters.

Use a "wave" rotor - the notched in the rotor may give you enough clearance to remove the wheel.

Use a 180 (or larger) rotor, and select a post mount adapters that places the caliper farther forward.

If a combination of the above still does not let you remove the wheel without lossening the caliper mount, and the interference is minimal, you can also shim the rear of the post mount with a washer to tilt the Avid caliper forward and clear the rotor. Slight misalignments of the pad - rotor will have a very minor effect on the brakes.

Simplicity may still be withing reach...

Cheers,

Tom
Tom, Your handle is right on. I never thought that there were that many solutions. It certainly is doable.

One other pseudo solution that I have not seen is going tubeless. This may eliminate or greatly reduce your need to deal with the rear wheel. Just a thought....and it is what I do.

One other thought....depending on the frame you are using....You might be able to add a link of a half link to the chain and get the axle far enough back that it will put the caliper at 12:00 and solve your problems (works with a KM frame...what are you using?)

Personally, I dont think 2 extra 4mm bolts to loosen is that big of a deal, You are already dealing with a bolt on hub...what is 2 more bolts? Either way, you are not changing a flat in record time....add to that the chain tensioner (tug nut)...Man, now that I think about it, MY SS is anything but simple!

This is a frequently debated topic here. Basically, you either find the bennefits of disc brakes worth the added hassle or you dont. Nothing is perfect for everyone.
 

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unit said:
This is a frequently debated topic here. Basically, you either find the bennefits of disc brakes worth the added hassle or you dont. Nothing is perfect for everyone.
Well, see, now that's the beauty of the Phil Wood setup- no hassle at all.

miles
 

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i have a P.U.S.S. frame with avid bb7 mechanicals and i never touch my brakes, even to make gearing changes. seems that proper calliper allignment and the avid wave rotor seem to be enough to give me proper clearance to get the wheel on and off.
 

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miles said:
Here's my setup. The caliper lives in front of the rotor, and once it's been setup for your wheel position (determined by gear sizes and chain length) it never moves when you have to take out the wheel.
This solution is so obvious yet have not seen it implemented on many bikes. THis would solve the entire EBB and paragon slider dropout for good. BTW what brake is that?
 

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crux said:
This solution is so obvious yet have not seen it implemented on many bikes. THis would solve the entire EBB and paragon slider dropout for good. BTW what brake is that?
Not sure how this "solves the entire EBB and paragon slider dropout", but all solutions are not without thier disadvantages. Hayes is the only caliper made with the R22 mount used on the KissOff. However, an ISO or Post mount can be used by modifying the seat & chain stay Junction, like in this setup:

Post mounts require more clearance on the seat stay, but you may not be able to use all the available calipers.

The main issue I've had with seat stay calipers is that reverse braking manouvers tend to pull the wheel out of the dropout unless you have the QR set really tight. It's not an issue for most people, but if you like rolling back on your rear wheel and doing a rear wheel hop (trials like manouver), that's often enough force to make the rear wheel shift in some frames. There is a reason why ISO mounts are placed (within a few degrees) in-line with the dropout.
 

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One clarification is in order. When refering to horizontal dropouts you need to specify conventional (forward facing) dropouts vs. track style (rearward) facing dropouts. Both are referred to as horizontal dropouts. Track style dropouts don't have the brake interference problems as you can see in Miles Kiss Off. It wouldn't matter if the Kiss Off had a seat or chainstay mount. With track style dropouts the wheel exits to the rear and never interferes with the caliper no matter where it's mounted. If you use a quick release instead of nuts in this setup you don't need a tool of any type to take the wheel out. I know you'll probably need a tugnut and some don't like to use quick releases but it makes wheel changes easier, especially on the trail.
 

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meloh1 said:
One clarification is in order. When refering to horizontal dropouts you need to specify conventional (forward facing) dropouts vs. track style (rearward) facing dropouts....
Technically, rear facing track mounts are NOT dropouts (sometimes called track forks), while the forward facing mounts are considered dropouts - the term "dropout" meaning the ability to remove, or drop out your wheel without removing the chain. But that's semantics & etymology, or a pet peeve, depending on your bent.

meloh1 said:
...With track style dropouts the wheel exits to the rear and never interferes with the caliper no matter where it's mounted...
Depending on your caliper, seat stay angle, seat stay mounted calipers can interfere with with rear entry track mounts, as many people here have found.
 

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I don't think you're going to see many conventional dropouts with discs.

I think it's fair to assume most people are talking about track dropouts. Track dropouts with the now-standard 51mm mount calipers can be a problem. The caliper sort of wraps around the disc. I have a PUSS with rear facing dropouts and Shimano brakes. I have to loosen the bolts and twist the caliper to get the wheel out. The mounts are slotted to allow this so it's not too big a deal and if I had the wheel further back in the dropouts the caliper would already be twisted a bit and probably allow the wheel to slide right out.

The reason the KISS OFF works is because it uses a mount style developed by Hayes and Trek (I don't think brakes with this mount are available anymore) that sits on the chainstay in front off the disc. It's not entirely perfect though. The thing that says "Phil" under the caliper is a slider that has to be used to make sure the pads cover enough of the disc. On the Roloff bike above, you'll notice that,while it uses sub11 dropouts, the drop outs face down, not back, making them really just super deep vertical drops that don't offer much chain tension adjustment. I imagine this was done to keep the wheel from being so far back that the disc is pulled out of the caliper. That design with true horizontal drops would only give you a few millimeters of adjustment at best.

I think the best design for rear facing dropouts with disc brakes is the slotted mount used by Bianchi, Surly and Spot. It's fairly simple and allows for a significant amount of adjustment. The only problem is the long tabs can bend under hard braking, but I've only seen that happen once.
 
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