z650 build

[rangeroy]

got this of a mate 3years ago

had a hard time trying to get a reliable tickover would run great above 2k,cleaned carbs balanced them,changed plugs & did the wired george fix to get 12v to coils, changed pilots all to no difference,then just by chance checked the vaccum pipe & its full of fuel the tap diaphram had a split in it & the engine was pulling fuel thru just enough to kill the spark at low revs but not enough to affect performance above 2k

[rangeroy]

hyvo motor

after running the single row cam chain engine for a while I swapped a similar bottom end for a hyvo chained bottom end, got hold of a hyvo cylinder head & put back together, I went down this route so I could use gpz 750 cams at some point.

hyvo motor complete

of course then i had another plan!! shed rebuild

old shed half gone

all gone

new base

new shed

I ran this motor for a short while, then of course the starter clutch gave up & no kicker fitted
Back to the drawing board & another plan, rebuild this motor with a gpz 550 six speed gearbox,zr7 starter clutch & oil pump, get hold of a set of z750 barrels & bore out to 810cc fit a gpz750 head & cams, upgrade with valve springs from APE & degree the cams, refit this motor after taking out a gpz750 unit thats in the frame now & then fuel inject using some gpz1100 throttle bodies & a megasquirt ecu

[mankam]

[rangeroy]

cam box off

this is the gpz motor that's sat in the z650 now

put a z650 sump pan back on the gpz motor because i dont need to run an oil cooler & gpz's have an oil level switch not a oil pressure like the z650, had to remove the blanking plug fom under the ignition rotor to fit a pressure switch

[rangeroy]

various parts

so moving on

&on

& on

get to this

get to this

finished

sold on the bay
back to z650

crankcase bolts

dry & tight as you like

old starter clutch out

[rangeroy]

gpz 550 6spd

crankcase put together & gear shift checked

zr7 starter clutch

zr7 starter clutch, secondary shaft & starter gear

test fitting

fitted with zr7 oil pump also

rebored barrels back

[rangeroy]

z650 clutch on left v zr7 clutch, no real diff after 20yrs just friction plates thicker but steel thinner

oil relief valves z650 on left

ape springs :-)

viton valve guide seals

all taking shape slowly

[rangeroy]

rev counter electronic

strobe revs

back working on this motor now its a little warmer needed to sort out a electronic rev counter as the gpz head has no cable outlet, bought a Suzuki gsx750f rev counter off ebay for £15 pulled it apart & stripped out the manual workings off the z650 rev counter, rebuilt & a quick bodge to the battery & coil pickup the check readings with strobe to see if they match on the rev counter face (close enough for me)

28mm mikunis

putting these on the rebuild to run the motor in before going down the injector route just to make sure all is good first

looks okay

bit tight underneath may have to make a manual cam chain adjuster