A right old 650 / 750 Mess

[kev edwards]

Ratch if you measure your frame from mounting lugs to mounting lugs i will see if the zephyr is the same and this may be a starting point for you.

Just measured and outside to outside of the zephyr frame lugs is 272mm.

[Crofty]

Hi Ratch, only just seen this post now. All you need to know has been mentioned.
Your frame is defo a 650 frame, your crankcases are GPZ750.
The 750 only mounted with the 2 bolts at the rear and the front had rubber mountings which are bulky and went to different mounts on their frames.
What you need to do is make up brackets and spacers to fit from frame to engine for both the top and bottom mounts at the front of the motor.
You should have no problem at the rear with std 650 mounting hardware.
The GPZ only mounted at the front with the 2 rubber upper mounts and the GPZ frame had a flat platform lower down that the cases sat on.
I have a section of GPZ frame with those bits on if you want to see a photo.
I may have the rubber mounts left over too if you want them, but fairly sure you cant use them in a 650 frame.
Never done the mod myself, but you could drop jb a line as he is running a GPZ750 turbo motor in a 650 frame. Crofty

[Royalratch]

Clear.

I'm going to have some spacers / brackets made but to get the correct measurements I need to centre the engine in the frame - which is obviously not that easy when you can't bolt the bloody thing in place?

I assume frame lug width minus engine lug width = spacer widths.

On the front mounts, the bottom 2 are equally spaced, the front top right requires a triangular bracket with integrated spacer. Front top left bolts straight to motor.

[Pigford]

That'l;l give you a chance to get the chain run spot on - the motor don't need to be 100% centre

[Royalratch]

Was thinking the same thing - may be a blessing in disguise lol.

I might get a lathe - wanted one for ages.

Any recommends for a 'desktop' thing that can handle hi tensile S/S...?

[Royalratch]

As Zed105 and other have pointed out, you can see the GPZ frame only use the top front mounts and the frame tabs are 'open' to accept the bushed mounts. The bottom mounst are just small tabs that the engine sits on.

Rear mounts are as regular 650/750



So just need to replicate parts 32029 and create spacers for front bottom from scratch - they don't exist.

[z1bman]

1 lenth of 25mm diameter aluminium round bar is all you will need to make all your spacers then get a machine shop to bore them out to 10mm

http://www.ebay.co.uk/itm/Aluminium-Rou ... 4ab173ecdf

[Charlie]

Looks like you are sorted now ratch.

I ran the engine number through the Kawasaki dealer portal this morning, but it does not go back far enough to cover that number.

It is certainly not ZR750 as I thought, as they started at KZ750EE150001

Jim will be on the nose with late model GPz750.

[Crofty]

Put the engine into frame with rear mounts, get some rod or a long engine mount bolt to run through the top front mount.
The rear mounts will hold the engine where it should be, then you can measure the gaps at the front to work out spacer length between the mounts and engine, simpelz.

[Z1parR]

Just checked my GPZ750 A3 and it's engine number is KZ750EE124611 , so Jim is bang on the money there
Also you're right that the bottom front mounts are not used, but the motor sits on the small tabs on the frame cross brace .

[Royalratch]

Awesome cheers lads.

One thing is odd - why does this motor have bottom engine bolt recess if they are not used?

Kawa diidn't change the castings...?

[Crofty]

Just a throwback to the earlier 650, they may of been thinking of using upper and lower at the front and decided not too.

[j.b]

from the gpz750R1 onwards kawasaki added a cross brace to the bottom of the frame down tubes which meant the lower front engine mount wasnt needed as an added stressed member for the frame.
on my bike i made the necessary frame braces and used the original z650 top mount triangle with bushes made to fit.