VMAX 1200 front brake reservoir sizes

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Frazvmax

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Hi, anyone know what is the standard size of the brake and clutch
reservoir piston holes, I've been offered a pair of levers. The brake res has 12.7mm piston hole and the clutch 14mm piston hole. At least thats what it says on the spec.Would these work? Just bought a 2002 vmax with a really strange pair of racing reservoirs and handle bar ( short flat bars ) hose set up on it and wanted fit normal bars and either standardise or even just smarten up the lever and hose setup, thanks.
 

Julian Tomkins

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how similar are the sizes of pistons in the master cylinders you have compared to what you are thinking of replacing with, if they are close and you are happy with how the existing ones work then you should be ok, smaller diameter piston gives more lever movement but too small a diameter and the lever will hit the bars without much brake/clutch effect, much bigger and you will lose 'feel'
I have just changed my master cylinders to XJR1300 items as my calipers were upgraded to MT-09 items and my standard master cylinder lever action was too solid, the XJR item has smaller piston and now I have movement and feel (read better control) of the braking action
 

Frazvmax

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Thanks Julien, I dont have the original reservoirs and the ones fitted are nissin race specials. This is why I'm trying to find what the standard size of the originals so I can
compare with the spec of the units I've been offered before buying them, once again many thanks. If you find the standard specs before I do please drop me a line or txt 07833401469, cheers, Frazer
 

Julian Tomkins

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the standard size of the pistons in both brake and clutch is 5/8, mine is a 1991 model so I don't know if it's different for the later models
 

mabdcmb@yahoo.com

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85-07 vmax all use 5/8" master cylinder for both the front brake and clutch.

You don't want to go any smaller than 14mm for either.

Installing a 14mm clutch master will make it easier to pull the lever. It will change the engagement point. It will be closer to the grip. I've found that it's barely enough to disengage the clutch, but it is enough.

With a 14mm master on the brakes, the lever will feel softer than stock. It will take more lever travel to apply the same force as stock. It will nearly bottom out in the grip of you are breaking very hard
 

Frazvmax

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85-07 vmax all use 5/8" master cylinder for both the front brake and clutch.

You don't want to go any smaller than 14mm for either.

Installing a 14mm clutch master will make it easier to pull the lever. It will change the engagement point. It will be closer to the grip. I've found that it's barely enough to disengage the clutch, but it is enough.

With a 14mm master on the brakes, the lever will feel softer than stock. It will take more lever travel to apply the same force as stock. It will nearly bottom out in the grip of you are breaking very hard
That's great, I've got a couple of options, many thanks
 

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