Norvil front disk brake conversions.

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Jul 26, 2011
Where in the US. might be the most economical source of Norvil-style Lockheed racing front disk brake conversion kits,
including all of the necessary parts,
to fit my 1975 Commando 850 Mk.IIA Interstate?

Many thanks!
I am doing the same for one of my combats. I have a PR wheel and hub for the 6 hole carrier and a PR M/C. I Just ordered the rest of the bits from Andover with one slider for the right side. I want to use my original PR master cylinder but it only has one output for the hydraulic hose. What is the means of adding the brake switch in the line? How did they do it for the original Production Racer's? I might change my M/C to 13mm bore but need to calculate the ratio for a single disk setup. Also I plan to use Euro bars instead of clip ons . I am getting too old for bending over, so what length of hydraulic hose do you use Ken?
+1 Steve, that’s a good set up and a fraction of the cost of the PR set up, which requires a new hub and slider and etc.
I only have rear brake light switch connected. if your ever chased at night you can get away without giving yourself away when you brake...
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According to this purported copy of a UK MoT test manual, referring to motorcycles, 'Machines first used before 1 April 1986 must have a stop lamp that operates from at least one brake control.' So, if that's correct – and I have seen it elsewhere – in the UK all of our Commandos only need one switch. Perhaps front switches were fitted (e.g. on BSA singles from 1967 onwards, according to my manual) to meet export requirements, mainly to the USA. Do you know what the situation is locally? If you're interested, of course!
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I have the RGM brake assembled from bits. Does anyone know how the brake lever shown in the above referenced link differs from stock? MKIII MC sleeved to 13mm.
The brake lever is the “racing lever” it is different from the standard lever, being longer and with a different cam shape. If you install this on the original master cylinder you need to make sure that brake pressure bleeds back into the reservoir after a brake application. Brake will lock up after about 15 mins riding otherwise. It may appear plug and play but needs correct set up!
I use the racing lever and it does improve the brake feel, not compared it to the 13mm master cylinder but I doubt its as much as an improvement as the master cylinder.
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