cam suggestions

[smokey]

im gonna be gettin a big bore kit soon, for my 79 gs 750e,the bore kit has 10-1/2 commpression ratio,i was wondering if some of you fellow gs heads had any suggestions for cams i dont wanna go to big i still wanna keep her streetable but im still lookin for a rip you off the bike midrange and were to get them thanx smokey

[first timer]

talk to these guys they should be able to help you out.

http://www.megacyclecams.com/

-ryan

[RacingJake]

You could always go down one tooth on the counter sprocket for more gearing. About 15 bucks and if you don't like it you can always go back to oem.

Set the cams up to 110 degrees to move the powerband up higher and always check valve to piston clearance. At least 75thou on exhaust and 50thous on intake to be safe.

The next thing you'll find out is you need a bigger rear tire :twisted:

[johnrregan]

Re: cam suggestions

im gonna be gettin a big bore kit soon, for my 79 gs 750e,the bore kit has 10-1/2 commpression ratio,i was wondering if some of you fellow gs heads had any suggestions for cams i dont wanna go to big i still wanna keep her streetable but im still lookin for a rip you off the bike midrange and were to get them thanx smokey

i take it you mean the 8 valve gs 750? dont bother with the expense of a big bore kit. the complete top end, head, cams barrels and pistons and carbs etc off the shaft drive gs850 will drop straight on, this is the only engine hop up using stock suzuki parts in the whole gs range of motors, and will give you a 100cc bigger motor, and a good chunk of extra power and torque yet shouldnt overstress the components, cos they are made to handle that kind of power anyhow. and it shoud be shedloads cheaper than a big bore kit!

[Idaho78GS550]

Top end swap?

the complete top end, head, cams barrels and pistons and carbs etc off the shaft drive gs850 will drop straight on

Will something like this work on my 78 GS550? Would I have to settle with a 750 top end or could I make the jump to an 850? Are there any other mods that would be required?

[johnrregan]

750/850

no, unfortunately not. whilst there are some parts shared across the 8 valve gs range, theres only one engine hop up that can be had by swapping the bits from one model to another, thats the 850 shafty head barrels etc onto the 750 cases. ive seen a 550 fitted with a 750 motor, but it would have to be the complete lump. though its possible that some of the 650 bits may be compatable, but ive never heard of anyone swapping them onto a 550 bottom end. i will enquire in the katana club if this is possible

[scotty]

the choice of cams on a head that does not have special guides is small--lots of work for little results. Listen to jakes advice.

[humhead]

i take it you mean the 8 valve gs 750? dont bother with the expense of a big bore kit. the complete top end, head, cams barrels and pistons and carbs etc off the shaft drive gs850 will drop straight on

I whish this was true! I tried it last year & found out that the 850 cylinder block does not fit on the 750 cases without machining the cases to remove the material that prevents the bottom of the block from sealing. Using an 80 or newer 850 head & carbs is a good idea.


Terry

[johnrregan]

gs 750/850

well, its a year or three since i did this conversion, but mine went straight on, with no glitches, no machining of the crankcase mouths , just a straight swap one for the other.

[humhead]

well, its a year or three since i did this conversion, but mine went straight on, with no glitches, no machining of the crankcase mouths , just a straight swap one for the other.

Hmmmm..... I wonder what I did wrong. I tried to fit the 850 block on the top half of a set of 750 cases & it wouldn't fit. There was contact in at least four spots between the bottom of the cylinders & the case. I was able to sand the contact areas until it would seat, but I didn't want to try this on an assembled bottom end for fear of damaging the working engine. I wound up getting a good deal on 3 78 1000s. The 850 project is on the 'back burner'.

Terry