TOPIC:

I have a 1978 KZ1000 that I am getting a valve job on. While the head is off I thought I may as well try to get some more power out of the motor with a hotter set of cams. I went to Star Racing, but when they arrived it turned out that I would need some machine work on the head to allow the new cams to fit. Stars Grind No. is Z4.

I told Star Racing my problem and was told that their Z2 would just drop in.

I have cam specs for Stars cams, but I do not have OEM specs to compare it too. I want to know if Stars Z2 is a higher output cam then stock.

If anyone has cam info on a KZ1000A I would appreciate the feedback.

I don't know the duration, etc. but the lifts are .297 exhaust and .315 intake. Not sure if these are for a Z1, KZ900 or KZ1000 but I'm sure they were all very close to being the same. These would be good enough for comparison. You will need to machine the head once you reach around .400 lift +/- a little. I believe .410 is the biggest cam you can run with shims on top and .395 is biggest you can run stock pistons, I think. I have older/new catalogs that list cams and their spec.s so if you or anyone needs spec.s I will look them up for you.

I believe most drop-in cams are about .365 lift +/- a few thousands.

I am at the same point with my 79 KZ1000, hope to be on the road in a couple of weeks. I wanted to keep the stock pistons because they only had 4400 miles. With a .365 lift cam and stock pistons is there enough clearance to shave the head any?

Thanks for the info. I just wanted to make sure that the new cams that I am waiting to receive will indeed be an upgrade from stock.

The one's I'm getting will have a lift of .385" and a duration of 258 degrees.

Do you think the performance improvement will be noticable or do I expect too much from a simple modification?

it depends on what the rest of your combination consists of.

I have a 1075cc kit with Mikuni 29mm smooth bore carbs and a new set of aftermarket cams.

That is the extent of my performance upgrades for the time being.

I also added a 37 tooth rear sprocket as opposed to the stock 35 tooth.