RGM Front disc brake 73-74 mudguard stays

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Onder

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Looking at putting a Grimeca caliper on my Mk2 850. Will using the RGM adapter plate (or the Norvil one) with the
standard disc allow for use of the stock rear mudguard stay? If I go with the larger RGM disc will that work as well?
Not one to go with the no stays look. Just don't care for it. "It's not stock"! Perish the thought! :)
 
It is possible to use the original mudguard stays, although you have to bend the lower mudguard stay a bit to clear the Grimeca caliper.

RGM Front disc brake 73-74 mudguard stays
 
If you bend the lower stay, will that not shorten it and then warp the mudguard around?
 
Or consider making your own extremely neat setup a-la @Matchless

Yamaha 4 pot caliper available dirt cheap on EBay ( I got mine for $40 including postage from the U.S.) + RGM disc.

You do need to helicoil the upper mounting lug as there is no room for a nut behind it though.

 
I did look at that. Would you PM me some photo details of the adapter? Or
post them right here if you don't mind.
 
I bent mine to get the fit, to make it longer I slotted the fork lower end and had a small section welded on to make it longer. I have a replacement ready which is 2 stays with offset cuts with smaller tube inserted and then welded. With std disc and Lockheed caliper you need 5mm extra length.
 
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Yes looks acceptable and answers my question. Not really happy with the slotted adapter but then that must be so you can fit a standard disk as well. Upon thought, seems slots not a worry with the bigger disk as the caliper will want to follow the disc and
that would really force the caliper outwards.
 
Yes looks acceptable and answers my question. Not really happy with the slotted adapter but then that must be so you can fit a standard disk as well. Upon thought, seems slots not a worry with the bigger disk as the caliper will want to follow the disc and
that would really force the caliper outwards.
 
I tried the bending option and didn't like the twisting force on the sliders needed to gain alignment for the bolt . So I cut the stay off inside the guard , going on 10 years and no comments on the 3 stays. If the next owner is a purest they can weld it back on but then they will have to reinstall the origional disc etc etc Cheers Ian
 
Make one out of 10mm solid alloy round to fit, I made my saddle bag supports with it and will make a stay for my guard but been running the front guard with the Grimeca set up without no problems after 10 years as well, but then I do look at my frontend when riding, love my Gremica set up, modern brakes on a old bike and one finger operation if I want to.
 
Have anyone had to add shims on the right side of the axle to let the rotor pins clear the lower fork tube ?
My friend is telling me that he needs.040” worth of shims on the axle or is he putting something together wrong.He has the Grimaca caliper with the RGM disc.Any thoughts?
Thanks,Mike
 
Mike, there is 2.5mm space between the fork leg and brake rotor with the RGM/Grimeca setup.
No spacers were added.
 
Mike, there is 2.5mm space between the fork leg and brake rotor with the RGM/Grimeca setup.
No spacers were added.
Thanks Peter,
I really think that my friend put something together incorrectly.
Mike
 
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