1977 KZ-650C1 performance parts

Some of you read an earlier post I created and I need a total rebuild on 1977 KZ-650C1 and I was wondering since I had to buy all new carbs and cylinders and stuff if there are any interchangeable parts or any performance parts out there that you tested and really found a difference. Anything will help. Thanks, Alex

Just get it running right and you'll have more than enough power for a go-cart. A stock '77 KZ650 puts out 64 HP. Ed

A rack of vm26 carbs (kz900/1000 or suzuki gs750/850 will all fit) will really wake a 650 motor up. You can drop in kz750 cams for a bit more low/mid power as well, or GPZ750 cams for full out top end.

All those parts will be readily available on ebay without spending a ton of money. Other than those bits you can get into having head work done (I hear great things about Larry Cavannah (sorry if I spelled that wrong Larry) and of course there's no replacement for displacement. If you're having to build a whole motor anyway why not try to source a kz750 motor instead? Just a thought.

First off all I'm gunna say to the first post is you can never go fast enough haha and I cannot simply buy a 750 motor because I'm on a tight budget.

Performance build and tight budget don't usually get along very well But if you want to get some extra juice outta the 650 motor dig around on ebay and watch for some vm26 carbs and 750 cams. You'll have to swap the sprockets on the cams with those from the 650 cams unless you get lucky enough to score a set that used the old style cam chain, not many of those out there though.

What year 750 used the same sprocket?

Some of the 1980 kz750 4 cylinders used the same cam chain set up as the early 650 motors. Part of the way through 80 they must have ran out of the old parts and switched to the hyvo cam chains that were used in the 81 and newer 650 and 750 motors. Some of the 80 750 cams will have the earlier link style sprockets, and some will have the later hyvo style sprockets on the cams. You can easily swap the sprockets off the 650 cams onto the 750 cams if you do find a set that are for the hyvo chain, just be careful that you're lining up all the timing marks appropriately when swapping the cams.

Okay that's good to know. And yes i know about timing. And finally about how much more power would come from this swap? 5 horsepower?

Also do all gpz750 cams fit? Does it have to be a specific year or do they all fit?

anarki650 wrote:

Some of the 1980 kz750 4 cylinders used the same cam chain set up as the early 650 motors. Part of the way through 80 they must have ran out of the old parts and switched to the hyvo cam chains that were used in the 81 and newer 650 and 750 motors. Some of the 80 750 cams will have the earlier link style sprockets, and some will have the later hyvo style sprockets on the cams. You can easily swap the sprockets off the 650 cams onto the 750 cams if you do find a set that are for the hyvo chain, just be careful that you're lining up all the timing marks appropriately when swapping the cams.

Have you ever actually seen a real 750 four motor with KZ750E stamped on the case, that had a roller cam chain?

Or are you basing this on previous discussions of what 750 cylinder blocks and heads will work with the 650 roller cam chain?

I have a 750E manufactured 8/79 that has the HyVo style cam chain, and I've never seen or heard of any 750 four having a roller cam chain. And kawasaki.com only lists the HyVo style sprockets and chain for 80 KZ750E1 and KZ750H1.

Not a big deal to swap the sprockets though, and as far as I can tell, the 80-82 (at least) E and H cylinder heads and blocks have provisions for the 650 roller cam chain.

Cookie1893 wrote:

Also do all gpz750 cams fit? Does it have to be a specific year or do they all fit?

That's the $64k question

MegaCycle says that some 83-85 GPz750 cams have a smaller base circle (would require much thicker shims) than others.
I've had 8-10 sets of 83-85 GPz750 cams, and they have all had the same base circle as 650/750 cams.

Might be some out there, I just haven't run across them.

If you still have a set give me a price and I'll maybe buy a set off of you.