Cam degreeing ?

Since I have a spare GPz head I was thinking a milded port clean up,
blend the bowl's and clean up around the guide boss's.

Take about 010 off the head and then degree the cam's
so should I go with the factory center line or
can I pick up a little with a small change ?

zukdave wrote: Since I have a spare GPz head I was thinking a milded port clean up,
blend the bowl's and clean up around the guide boss's.

Take about 010 off the head and then degree the cam's
so should I go with the factory center line or
can I pick up a little with a small change ?

Dave,

Punch the throats out to 91% of the valve diameter on the intakes and 90% on the exhausts. Watch grinding too deep on the long side of the bowls on 750 heads. There's not as much meat as the KZ900/1000 head in that area.

Do that first....run the bike at the track.....see if it buys you anything, then degree the cams. The 82 GPz 750 heads had really big exhaust ports. Not sure what year yours is.

If you could scrounge up a rack of old 33 smooth bores to try on it, you might pick up some MPH.

It's an '83 model.

I was thinking just a little cleanup with some sanding roll's
and not go grinding the shit out of it.
Bump the comp. a little then degree the cams I may pick up a little.

I've got all the gaskets from base up so I could do this with no money out
of pocket.

zukdave wrote: It's an '83 model.

I was thinking just a little cleanup with some sanding roll's
and not go grinding the shit out of it.
Bump the comp. a little then degree the cams I may pick up a little.

I've got all the gaskets from base up so I could do this with no money out
of pocket.

.010" off the deck isn't worth taking the head off IMO. Why don't you fiddle with aerodynamics and the exhaust system instead. Also look at your drive chain. Make that thing roll as free and easy as you can possibly make it. Loose as much weight as you possibly can off the bike. Get it as "down on the ground" as you can get it.....It runs pretty darn good right now.

If you do work on the head, don't polish the shit out of it with sanding rolls. Use a 6" single cut carbide to level down casting seams instead. The bowl & the throat are where the airflow happens. A standard 750 flows 69CFM @10". Yours is probably mid 70's stock. 29 smoothbores [depending on how you set up the flow test] flow about 83CFM. Think that part over a while....you'll see why I say give it some bowl and open the throats

Larry I was looking at the spare head and
the intake valves are flush with the head gasket surface
is this stock or maybe the heads been cut all ready.

I'll put up pic.s in the morning.

zukdave wrote: Larry I was looking at the spare head and
the intake valves are flush with the head gasket surface
is this stock or maybe the heads been cut all ready.

I'll put up pic.s in the morning.

That's stock, you have to remove at least the intakes before cutting the head.

Friend of mine cut the head .025" on his 83 Gpz750 when he installed a 810 kit.
He was so happy with the results he sold his GS1100E and kept the 750

zukdave wrote: Larry I was looking at the spare head and
the intake valves are flush with the head gasket surface
is this stock or maybe the heads been cut all ready.

I'll put up pic.s in the morning.

Dave,

I completely missed that it was s spare head....[speed reading] my bad...

Take it apart and see what shape the valve seats are in. I've seen 750's chip pretty badly sometimes.

I'm going to clean this one up then sent the
low milage one I take off to someone that's postin here.
Here's some pic's.