Larger 1982 KZ750E3 cams?

Does anyone make a larger than stock camshaft for a 1982 KZ750E3? At the point with my bike where I'm going for more motor performance related upgraded. I have k and n filters, larger jets, Vance and Hines exhaust and dyna ignition and plug wires. Bike runs great. Any ideas or suggestions as to what else I can do?

Bike in question.

Edit

I take it you don't go on long trips or ride in the rain. :whistle:
Steve

i like the question mark with the Iron Cross, really unique.

The later zx unitrack GPz750 cams had more lift and duration, I think the base circle is reduced so whether you can swap I'm not sure. IIRC it is about 0 .5mm more lift plus 286 degrees over 270.

Nothing in life is free, the GPz tune is more 'cammy' , great if you like that , my 550 and 1100 are like that. On my 750R I quite like the stronger midrange, I have a spare zx motor but might keep it just as it is.

Are you looking for rpm redlne power or stronger midrange?

Careful what you wish for, my 750 I have yet to have flat out, always seems more than i need for road use so I rarely take it over 90mph. Personally I wouldn't want a 130 mph bobber.

A proper jet kit and 530 chain with 15/40 sprockets.
These will get you very snappy performance.
Have you checked valve clearance? Compression?

.

My 750R1 was feeling pretty tired when I got it, one pot was badly down on compression and several of the valve clearances quite a lot out. I've yet to recheck the compression but I think the rings were gummed up, Putting a few hundred miles on it and a touch of redex fuel treatment seems to have perked it up loads, plus the usual replacement HT leads, plug caps, carb service and oil change.

I suspect maybe it needs a tune up, rather than power tuning. What size main jets are you on?

The 750E are 74 bhp, not far down on the GPz750R1. The GPz750 was the quickest factory 750, as CYCLE WORLD recorded an ET of 11.93 sec in the 1/4 mile. The later zx750 unitrack was 85 bhp, finally the zx750 turbo made a staggering 112 bhp.

swest wrote: I take it you don't go on long trips or ride in the rain. :whistle:
Steve

No riding in the rain for me. And iv ridden it for 2-3 hours at a time. Doesn't bother me much.

Tyrell Corp wrote: i like the question mark with the Iron Cross, really unique.

The later zx unitrack GPz750 cams had more lift and duration, I think the base circle is reduced so whether you can swap I'm not sure. IIRC it is about 0 .5mm more lift plus 286 degrees over 270.

Nothing in life is free, the GPz tune is more 'cammy' , great if you like that , my 550 and 1100 are like that. On my 750R I quite like the stronger midrange, I have a spare zx motor but might keep it just as it is.

Are you looking for rpm redlne power or stronger midrange?

Careful what you wish for, my 750 I have yet to have flat out, always seems more than i need for road use so I rarely take it over 90mph. Personally I wouldn't want a 130 mph bobber.

The question mark is from the Indian Larry logo. Always been a fan of his work.

What do you mean by tune? Like computer module or something?

More power in general is what I'm looking for. Open to suggestions tho. And yes I feel like I can never top out my bike. Always seems to have more go.

Nebr_Rex wrote: A proper jet kit and 530 chain with 15/40 sprockets.
These will get you very snappy performance.
Have you checked valve clearance? Compression?
.

I need to count the teeth on my sprockets and see what I have. With the sizes you suggested take away from the high end power?

I have checked valve clearance. It's not bad but it's not great. Will have them properly adjusted during the winter time. Compression will be tested then as well.

Tyrell Corp wrote: My 750R1 was feeling pretty tired when I got it, one pot was badly down on compression and several of the valve clearances quite a lot out. I've yet to recheck the compression but I think the rings were gummed up, Putting a few hundred miles on it and a touch of redex fuel treatment seems to have perked it up loads, plus the usual replacement HT leads, plug caps, carb service and oil change.

I suspect maybe it needs a tune up, rather than power tuning. What size main jets are you on?

The 750E are 74 bhp, not far down on the GPz750R1. The GPz750 was the quickest factory 750, as CYCLE WORLD recorded an ET of 11.93 sec in the 1/4 mile. The later zx750 unitrack was 85 bhp, finally the zx750 turbo made a staggering 112 bhp.

Not sure of the sizes of jets. They were upgraded befor I got the bike.

Anyone?

By tune I mean do you want grunty midrange or an arm wrenching redline rpm power, then you decide what you want and tune it accordingly.

The online megacycle cam catalogue is quite interesting, they have several different grinds.
This where you need to know what you want.

On the 550 they use the early stock kz and GPz cams, but don't compare the later zx550 models cam, so I suspect their mildest grind may be not a lot more than a later factory zx550 cam.

Maybe source a decent zx750 unitrack motor, but for only 11 bhp more you might not be happy.

Have you done a complete usual service and tune up yet? Even fast on the motorway my 750 always seems to have plenty of power. It has done over 43k miles so it is past it's first flush of youth.

On the subject of cams... Is it correct the 1983 Gpz750 cams are set to the z6ex mark not z7ex as stated in the 1981 manual. I have the 1981 manual with the 1982 & 1983 supplements but can't see any reference to different settings. It only refers to 1983 not having speedo gear drive on the ex cam and for the remainder of the set up it says it's the same as previous model ie set at z7ex? If anyone can confirm it would help me out. Cheers Brian

Megacycle sells cam regrinds for the 650/750. According to their catalog their 471-00 grind (the most mild they sell) is the only one available that will work with a stock engine.

CAM VALVE DURATION LOBE INTAKE OPEN/CLOSE RUNNING
NUMBER LIFT AT .040" CENTERS DESCRIPTION AND APPLICATION EXHAUST OPEN/CLOSE CLEARANCE
471-00 .354" 254° 110° OK with stock pistons and springs. Mild increase 17 btc/57 abc .004"
.354" 254° 110° in power from 3800 to 7500. Good mid-range. 57 bbc/17 atc .004"