Z650 front brake conversion

[jimmyjaffa]

Hi all, have just bought my first bike, a 77 Z650 b1. It has the standard single 295mm solid front disc setup. I am looking into converting to twin disc. I have bought to 4 hole 295 mm cross drilled discs and was wondering if the calipers of a gpz would fit straight on? If not what calipers would I need? Calipets mount to the front of the forks. Many thanks, jim.

[Gosling1]

the only calipers which will fit those early forks are the Z-style calipers mate, not GPz style. Check US ebay, you can often find the additional r/h side caliper for the z650's for sale. A r/h caliper from any model z650 up to 1980 will fit your forklegs.

You should also be able to use calipers from either the 1976 Z900A4, 1977/78 Z1000A1 / A2 or any of the calipers from the 1979/1980 Mk2 range of models - Z1000MkII or Z1R MkII. All these calipers use the same spacing between the bolts as your 77 Z650. These calipers can be mounted forward of the fork leg or at the rear - personally I always fit the calipers to the rear of the fork legs as this makes changing direction easier (all that weight is lower). You just need to swap the forks across from one side to the other to mount the calipers behind......

If you had a later model 650 - say from around 1981 onwards - these had the same forks & wheels/discs etc as the GPz models from that era, and you can use GPz750 calipers.

Good luck - and some pics of your bike would be nice - there are a few of us here that own the mighty z650. Great bikes.......

[jimmyjaffa]

Hi gosling1, thanks for the advice, looks like I will be swapping the forks around and looking for a pair of calipers. This is the first mod I want to do as I think I would like to make sure I can stop correctly. Then I will be doing the dyna electronic ignition, coils, leads and plate.

[Gosling1]

no probs mate - finding a pair of calipers should be easy. There are caliper re-build kits available from Jeff Saunders at Z1 Enterprises - the website is here.. Braided lines from Hel would be a good addition, and I use EBC pads in all my old zeds.

Master cylinder upgrade is easy - just find a late-model m/c from a ZX6/ZX9/ZX12R. These are rectangular and retain the 'old-school' look. If you want to keep the OEM m/c, you can also get piston kits for these from Z1 Enterprises.

You can retro-fit OEM kawasaki electronic ignition to these models easily - I am not really a fan of Dyna stuff, seen a few dud ignitions over the years - but rarely with OEM kawasaki stuff. US ebay is a great source of parts for these bikes.....including ignition stuff. All you need is the mechanical advance to suit electronic ignition, the backing plate with the 2 igniter coils, an IC igniter box, and a pair of OEM coils from a later 650/750.

[jimmyjaffa]

Hi, I want to get rid of all of the old points ignition system as its giving me a load of trouble, like the coils breaking down and having a crap spark. I want to fit a hole new electronic ignition system but there's a few out there and don't know quite wich to choose. Dyna everyone seems to rave about, Boyer Bransden and if I keep the point there's one called hondamans transistor ignition. I need advice about what are the best coils to get etc , Jim

[Gosling1]

get original kawasaki ignition from a later model z650 or Z750.

You just need these bits:

Mechanical advance mechanism
Backing plate with igniter coils
IC igniter box
Ignition coils

you can get all this stuff directly from UK or US ebay for less than the price of a Dyna 2000. It will bolt straight in and work properly from the start.

Stay with OEM stuff when it comes to the ignition system. It is far more reliable than any of the aftermarket stuff.