Rgm brake upgrade,

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Am sorry if this has been covered before, but had a quick look and couldn't see what am looking for.

But am busy fitting the rgm race brake kit to my 72 750, but what am finding is when am tighting the wheel spindle the disc clips hit the fork leg and lock the wheel, so is there a space or some thing am missing to push the wheel or fork leg out.

Any help with this would be great so I can get it sorted or i'll just have to wait unit rgm are open again.
 
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The disc clips will be very close but not touching, have you put the spindle spacers the right way round on the hub. Parts 20 and 21, 20 is non disc, 21 is disc side.

 
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Hi Kommando, yes I put the spacers in the same way they came off which is same as the drawing, and the clips have hit the fork leg, that is why Ive walked away to see were am going wrong with this.
 

acadian

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The disc clips will be very close but not touching, have you put the spindle spacers the right way round on the hub. Parts 20 and 21, 20 is non disc, 21 is disc side.

The item list description on the Andover page appears to be incorrect, showing #21 as "non disc side"
 
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Fast eddie, yep wheel is in the middle (best I can do by myself), what it looks like it needs is a 2mm spacer, don't know if originals worn/material removed, taken in out a fair few times today and each time its the same, so starting to grab at straws

If somebody else has this disc setup could you measure the depth of the clip head, or even the spacer depth.
 
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I also have the RGM front disc setup, already in use for several years. Indeed, the pins are close to the fork leg, there is just slightly less than 1mm of space, but not touching.
Dumb question perhaps, but is the dust cover (item 20 on the AN drawing) on the disc side in place ?
I measured the depth of the clip head, it protrudes 1.4mm from the alloy disc center.
 
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Hi Peter R, its part 21 on the disc side, thanks for measuring the clip head, mine is 1.4 mm as well, so that rules that out.
 

acadian

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Is the disc centered between the pads or offset as well?

The disc side spacer measures approx. 19.4mm
IMG_3318.JPG


It's not uncommon that a spacer is needed, here is a 2mm spacer that I had to machine sometime ago (different setup, but same problem)
IMG_3319.JPG
 
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Am sorry if this has been covered before, but had a quick look and couldn't see what am looking for.

But am busy fitting the rgm race brake kit to my 72 750, but what am finding is when am tighting the wheel spindle the disc clips hit the fork leg and lock the wheel, so is there a space or some thing am missing to push the wheel or fork leg out.

Any help with this would be great so I can get it sorted or i'll just have to wait unit rgm are open again.
Many years ago I fitted the Fair Spares disc system and had to file 1-2mm off the inside of the fork slider to clear the disc itself. My new RGM disc and new oval sliders have about a 1mm gap to the disc clips and no filing is necessary. Perhaps you have the round fork sliders and they need to be relieved by some judicious filing. Adding an additional spacer will push the sliders apart which may or may not be a problem with stiction and bush wear longer term.
 

acadian

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Many years ago I fitted the Fair Spares disc system and had to file 1-2mm off the inside of the fork slider to clear the disc itself. My new RGM disc and new oval sliders have about a 1mm gap to the disc clips and no filing is necessary. Perhaps you have the round fork sliders and they need to be relieved by some judicious filing. Adding an additional spacer will push the sliders apart which may or may not be a problem with stiction and bush wear longer term.
The larger OD on the non disc side of the axle passes through the LH slider and presses against the dust cover, leaving a gap between the spindle boss on the slider and the hub. As long as there's some clearance there the sliders will not be pushed apart.
 
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Hi acadian, just measured my spacer, it comes it at 19.36 mm so not that much difference, best I can tell disc is in middle of caliper, so it looks like it needs a 2mm spacer to give me the clearance.

Thanks for all your help
 

acadian

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Hi acadian, just measured my spacer, it comes it at 19.36 mm so not that much difference, best I can tell disc is in middle of caliper, so it looks like it needs a 2mm spacer to give me the clearance.

Thanks for all your help
If the disc is in centered in the caliper then I would not use a spacer, the spacer is only useful if the problem is with the entire hub/disc assembly being improperly spaced, I would look to rectify the clips instead. Have you pinged RGM to ask their opinion?
 
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If your disc is centered in the caliper, the wheel is centered between the legs and your clips are 1.4mm high then you probably have a thickly cast leg on the disc side. In that case it needs thinning on the inside of the leg to restore clearance.
 
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Thanks for all the help, spoke to RGM today, yes they say 1 in 50 have this issue (just my luck) so they will sort out shims I need to keep disc off leg, caliper has shims in kit so I should be able to shim that as well,
 
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