Disc break caliper placement.

Wolf Wizard /

So maybe a dumb question, but I've never had to custom mount a caliper before. Are there specs to how far away the rotor should sit, or how much clearance between the rotor and the pads? The gap between the pads almost seems too small, but I was told the gold caliper from treats was great for the cr80 rotor (cr80 rotor mated to this k100 wheel via a machined spacer. The wheel came with no rotor and they are hella expensive, and had this cr80 one around for a while.)

It fits in the nook super well and seems like I can make it work with some custom mounting tabs, but no matter where I hold it, and this might be me being a human who obviously cannot hold something perfectly still, cannot spin the wheel with the rotor there without constantly hearing a very slight rubbing of the pads on the rotor, which leads me to my secondary question. is that normal and does that noise go away when the pads "break in" some?

Any help much appreciated, plan on doing en entire write up on this swap when it's done.

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Re: Disc break caliper placement.

Baron Von Hamilton /

Dude I just went at it then used shins so it did not rub and everything was gravy....I say go in and don’t overthink.

Re: Disc break caliper placement.

Wolf Wizard /

I'm also worried because i had the caliper in storage for a while and one of the pads was crooked when i found it again. After messing with it, i ended up taking it out and learned how much of a bitch these pads are to put back in. i got it in but I mangled the metal vibration shim a little bit, but think I got it back to usable for sure.

Re: Disc break caliper placement.

Wolf Wizard /

so what i did was sat the caliper in the nook ontop the rotor so that it was laying on it flush. i then gently lifted one end, and put a piece of 18g wire on the edge of the rotor and set the caliper back down, holding it in place, then did the same to the other side. now the caliper height wise should be "hovering" that same distance the whole way around. I then marked where the two mounting holes will generally be on that old shock mount. i think this should get this "hover" very close. Moped close.

I think the net step is to grind away where i want the mounting holes to be and but some 8mm ID spacers, I'll then weld these in flush with the back of the shock mount (using a plate) so that the rotor does not sit cooked. And shim the left to right accordingly to get it so that jussssst done touch the static pad that does not move.

Should be able to get it done in a week or so.

Re: Disc break caliper placement.

Radial mount calipers are where its at.

Re: Disc break caliper placement.

Dirty30 Dillon /

It would be much more ideal to have the caliper mount move with the rear wheel, because now everytime you adjust your chain tension it's going to move the disk inside/outside the range of the caliper

Re: Disc break caliper placement.

Wolf Wizard /

Oof you’re totally right. Although the wheel only fits correctly when pulled all the way back, I was thinking about using a half link to get the chain where I needs to be tension wise. Ive never done a rear wheel disc, so I’ll have to look at some other setups for sure and see if I can’t makenit move with the wheel

Re: Disc break caliper placement.

Dirty30 Dillon /

> live ɘvil Wrote:

> -------------------------------------------------------

> Radial mount calipers are where its at.

Let's see the radial mount calipers on your moped.

Re: Disc break caliper placement.

Not too difficult, I welded a triangle plate to an axle spacer, slipped it on and spaced it so it’s not hitting. Put the caliper on the rotor to figure how to bolt it on. It’ll swing around the axle and u can figure where u wanna put it. To get the clamping to the rotor part good, squeeze the lever and tape it down. If there’s pressure it should be working like normal ;) clamp the rotor up how it fits. Mabe stick a piece of cardboard in the caliper first to keep it for bottoming out inside. drill, weld, space the axle spacer triangle to meet the caliper and join them. Have fun it’ll be neat.

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Re: Disc break caliper placement.

Kids like diS

A11FE31F-2223-4280-8DB3-02D0060335B0.jpeg

Set the caliper,

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Dirt wipe the bolt pattern,

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Then u can swing it over and tab it to your swing arm.

Re: Disc break caliper placement.

Arts and crafts dude, good luck.

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Re: Disc break caliper placement.

Slip a piece of thick paper over ur static pad before clamping the caliper to the rotor, that will set it from rubbing. Yeah lay some cardboard strips in there, that’ll keep it hovering and you’ll be able to smash the caliper on all the way.

Re: Disc break caliper placement.

Wolf Wizard /

I saw one of these and thought this is totally the way to go! In the second photo you can see that super chunky spacer I have in there, I can take some plate steel and bunch a hole in it the size of the spacers OD. Weld and then mount the caliper to it and mount the whole thing to that old shock mount to keep it in place! Might have to trim them bolts down that are holding the spacer though haha, they are counter sunk behind the other spacer on the other side of the wheel.

Also good looks on using a sheet of paper between the rotor and static pad.

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Re: Disc break caliper placement.

That chunky spacer it perfect! Dope

Re: Disc break caliper placement.

Wolf Wizard /

Hey scoot! I finished my mount tonight and it turned out awesome! Will be doing a full write up on the bk100 wheel swap soon in another thread. Whats the minimum clearance I should have between my caliper's static pad and the rotor you recon? I have the caliper pulled as far as I can, it's tightened down to my mount with now shims or spacers and i can fit my .635 and .559 feeler gauges between my rotor and pad. So I have about 1.2mm of space between the rotor and pad. Too much? I figure too much could warp the rotor or damage the pads. I can file away some of the surface where the mounting holes are so bring it out more if I need too.

Re: Disc break caliper placement.

Wolf Wizard /

Oh wow okay just realized that whole side can move I’ve never done custom caliper stuff I thought only the piston side moved. So when I press my brakes will it automatically move the outer, non piston side into where it needs to be as well? Second image is me pulling on the caliper, it will stay there but I can also push it back.(edited)

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Re: Disc break caliper placement.

> Wolf Wizard Wrote:

> -------------------------------------------------------

> Oh wow okay just realized that whole side can move I’ve never done

> custom caliper stuff I thought only the piston side moved. So when I

> press my brakes will it automatically move the outer, non piston side

> into where it needs to be as well? Second image is me pulling on the

> caliper, it will stay there but I can also push it back.

Ya, thats called a floating caliper. Once upon a time back in the 70s those did not exsist.

Re: Disc break caliper placement.

Wolf Wizard /

Ahhhh shit, I remember reading about them when trying to figure out how to mount this rear. If I remember correctly I should just bolt up my caliper so it does not rub and there is no noise, then loosen the large bolt that has the rubber cap on the other side of the caliper, (circled in red not the banjo) and have some then pull the brake lever and actuate the brake, it should clamp down hard then I re tighten the bolt before they let off right? Or am I totally wrong. I learn really good from watching and doing so sometimes I struggle just reading a description off an old motorcycle forum post(edited)

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Re: Disc break caliper placement.

The pad to rotor clearance on hydraulic calipers set themselves once you've bled them and squeezed the master cylinder, that's the beauty of them vs. mech calipers. Clamping a spacer between them when bleeding won't set the clearance that only works on mech calipers. It won't rub, and if it does that means one of the pistons is sticking which you can usually fix with a little penetrating oil and a c clamp.

for mounting, you want to set up and bleed a brake system then clamp the caliper onto the rotor so that the rotor has a few mm of clearance between the bottom of the caliper. when the caliper is in the desired position use that to create your brackets.

Re: Disc break caliper placement.

Wolf Wizard /

Thank you so much man! That clears it for me and the caliper bracket is done! Doin a write up today of the wheel swap!

Re: Disc break caliper placement.

Mikey Antonakakis /

I just did this a few days ago, slightly different caliper, but very similar. I made the mounting tab/bracket first, then bolted it up to the (already bled) caliper. I had to add some grease to the floaty mechanism pins, they were sticking a little. I then positioned the caliper on the rotor, pumped the lever a few times to get it to bite, and moved the floating stuff to about it's middle position/stroke (or I may have done that before I pressurized the brakes). Held the lever down with some electrical tape to keep the pressure, and tacked up my bracket. Worked great. I don't necessarily have clearance, the pads may be just sliiiightly touching the rotor, but they aren't providing any resistance. Wheel rolls nice and smooth, and the brake is super powerful.

Re: Disc break caliper placement.

figured out how to snip from insta. Bracket floats with axle.

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Re: Disc break caliper placement.

Mikey Antonakakis /

> Michael Thomas Wrote:

> -------------------------------------------------------

> figured out how to snip from insta. Bracket floats with axle.

> >

Sweet!!

Re: Disc break caliper placement.

Bless you Mike Thomas, and I'm sad I never got to kick it with the Tom Cruisers. (Maybe in the top three gang names of ALL TIME)

And Nate, you are a blessing to the MA forums, and your build is quickly becoming one of my favorites ever. You are inspiring me to do this with my chopper. Great info here! Thank you and keep it up!

Re: Disc break caliper placement.

Wolf Wizard /

mike, Yours looks awesome! i like the idea of the permanent stay that is slides on, I went much simpler with a slot and a bolt welded onto mine to hold it down in position!

Charlie, Thank you so much man for the support and kind words <3 ive actually made QUITE a few changes to my entire set up, trial and error style. will be updating my big old mega thread soon on that rigid rear and brake setup, what I will say is the brake held up super well after 50 miles of Pittsburghs finest hills.

Re: Disc break caliper placement.

I will say you gotta be exactly parallel, that's pretty critical, if it's not aligned right it can't self center. Also I've had old calipers be real sticky on the fixed pad sliding pins (probably a more proper term) and thatd keep em from centering well too

Re: Disc break caliper placement.

Also that setup Mike posted is sick, as is the BMW swap, fucking great build

Re: Disc break caliper placement.

Wolf Wizard /

Yeah! the bracket is for sure parallel and welded to a spacer, there is a thread of the whole conversion where you can see mine, (deff not as nice as his but does the job!) It got me 50 miles all over the huge hills in Pittsburgh!

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