Stock KZ1000 Camshaft technical info

I was hoping to get some help with the correct specifications for the stock camshafts on a 1978 KZ1000 A2. Primarily, what I am interested in, is what angle the lobe centers should be set to from the factory. Also, I would like to know if there were any good changes that can be made with the stock cams for a street driven bike. I am interested in degreeing my stock cams just for informational purposes. I would like to see how close they are to correct with the stock pulleys, and if I could change the timing a little to change the power delivery.

My current engine setup is a 78 1015cc motor with stock pistons and bore. I have changed to a welded KZ900 crank since my alternator was spun on the original crank. I still have the VM26 carbs for now with pods and a 4 into 1 exhaust. Like I said before, this is strictly a street driven bike. I already have a hot rod bike, so I want this to pull well from a stop to the midrange. It doesn't kill me if I don't have the ultimate top end performance. Thanks in advance for your help.

stock is 110. 104 to 105 on both is good for 4to5hp and a good broad power band. You'll leave the stop sighns with alot more gusto.. Then I'll blow by you around 80 and you'll wish u were on your other bike, cuz I would'nt set mine nowhwere near that :woohoo:

testarossa wrote:

I was hoping to get some help with the correct specifications for the stock camshafts on a 1978 KZ1000 A2. Primarily, what I am interested in, is what angle the lobe centers should be set to from the factory. Also, I would like to know if there were any good changes that can be made with the stock cams for a street driven bike. I am interested in degreeing my stock cams just for informational purposes. I would like to see how close they are to correct with the stock pulleys, and if I could change the timing a little to change the power delivery.

My current engine setup is a 78 1015cc motor with stock pistons and bore. I have changed to a welded KZ900 crank since my alternator was spun on the original crank. I still have the VM26 carbs for now with pods and a 4 into 1 exhaust. Like I said before, this is strictly a street driven bike. I already have a hot rod bike, so I want this to pull well from a stop to the midrange. It doesn't kill me if I don't have the ultimate top end performance. Thanks in advance for your help.

Use a new cam chain and just bolt them back in the motor with stock timing marks. If you pull the centers down to 106 or so you can pick up a little more peak torque but overall the 110 centers are just fine for a stock motor.

Torque can be increased at the peak or spread around a little. You can't get both from cam timing changes

It will rev as little quicker with the lighter 900 crank anyway.....

nads.com wrote:

stock is 110. 104 to 105 on both is good for 4to5hp and a good broad power band. You'll leave the stop sighns with alot more gusto.. Then I'll blow by you around 80 and you'll wish u were on your other bike, cuz I would'nt set mine nowhwere near that :woohoo:

Thanks for the information on the stock separation angle. I couldn't seem to find it by searching last night.

I guess that I am confused by this statement. If I tighten the separation angle to 105 then I gain 4-5 hp and broaden the power band, but I'll loose the top end? Usually horsepower gains are made at the top end with all else being equal. Are you speaking about gaining mid-range hp? Have you actually tested this on a dyno? I'm sorry, and I'm not trying to bust your balls, but some of this information seems to conflict with what I have read elsewhere.

After reading through OMR's "Motorcycle Cam Degreeing for Zombies." I took the link to Web Cams calculator and I found this little chart:

VARYING LOBE SEPARATION ANGLE
Tighten
Moves Torque to Lower RPM
Increases Maximum Torque
Narrow Powerband Higher Cylinder Pressure
Increase Chance of Engine Knock
Increase Cranking Compression
Increase Effective Compression
Idle Vacuum is Reduced
Idle Quality Suffers
Open Valve-Overlap Increases
Closed Valve-Overlap Increases
Natural EGR Effect Increases
Decreases Piston-to-Valve Clearance

Widen
Raise Torque to Higher RPM
Reduces Maximum Torque
Broadens Power Band
Reduce Maximum Cylinder Pressure
Decrease Chance of Engine Knock
Decrease Cranking Compression
Decrease Effective Compression
Idle Vacuum is Increased
Idle Quality Improves
Open Valve-Overlap Decreases
Closed Valve-Overlap Decreases
Natural EGR Effect is Reduced
Increases Piston-to-valve clearance

OMR's tutorial is an excellent resource for those who are interested in learning to degree their own cams.

larrycavan wrote:

Use a new cam chain and just bolt them back in the motor with stock timing marks. If you pull the centers down to 106 or so you can pick up a little more peak torque but overall the 110 centers are just fine for a stock motor.

Torque can be increased at the peak or spread around a little. You can't get both from cam timing changes

It will rev as little quicker with the lighter 900 crank anyway.....

Thanks Larry. I was hoping that you would chime-in. I figured that you would say this, but I had to ask anyway. Who am I to question what Mother Kaw decided was the best timing for the stock cams. BTW I did put a new Tsubaki cam chain in there.

it wouldnt hurt to check them anyway after installing them,theres always room for error when youre pushing 1000s of anything out the door on the assembly line.

testarossa wrote:

nads.com wrote:

stock is 110. 104 to 105 on both is good for 4to5hp and a good broad power band. You'll leave the stop sighns with alot more gusto.. Then I'll blow by you around 80 and you'll wish u were on your other bike, cuz I would'nt set mine nowhwere near that :woohoo:

Thanks for the information on the stock separation angle. I couldn't seem to find it by searching last night.

I guess that I am confused by this statement. If I tighten the separation angle to 105 then I gain 4-5 hp and broaden the power band, but I'll loose the top end? Usually horsepower gains are made at the top end with all else being equal. Are you speaking about gaining mid-range hp? Have you actually tested this on a dyno? I'm sorry, and I'm not trying to bust your balls, but some of this information seems to conflict with what I have read elsewhere. Dale Walker (owner holshot performance) has a cam degreeing video and on that video he states ,, for degreeing yourt stock cams on either suzukis or kawasakis, move lobe centers to 104 to 105 for an increase of 4 to 5hp and a good broad power band. Basically what your doing there is moveing the power band peak down just a bit. With the intake opening earlier the engine gets more charge in the cylinder, and closes earlier increasing cranking compression. Add the now retarded exhaust cam opening later (allows more burn time torque is increased) and the fact that it closes later ( is open longer while the intake is open and drawing in charge) the result here is more fuel charge pulled into the chamber (scavenging). I personally would stick with 106 since piston to valve clearance starts to get close with the intake valve close to the piston on the intake stroke. The clearance should be measured on both valves just for peace of mind. I'm sure the power will increase and I think you'll like how it will be. It just won't be quite so forgiving when you miss a shift since clearance won't be what it use to be.

After reading through OMR's "Motorcycle Cam Degreeing for Zombies." I took the link to Web Cams calculator and I found this little chart:

VARYING LOBE SEPARATION ANGLE
Tighten
Moves Torque to Lower RPM
Increases Maximum Torque
Narrow Powerband Higher Cylinder Pressure
Increase Chance of Engine Knock
Increase Cranking Compression
Increase Effective Compression
Idle Vacuum is Reduced
Idle Quality Suffers
Open Valve-Overlap Increases
Closed Valve-Overlap Increases
Natural EGR Effect Increases
Decreases Piston-to-Valve Clearance

Widen
Raise Torque to Higher RPM
Reduces Maximum Torque
Broadens Power Band
Reduce Maximum Cylinder Pressure
Decrease Chance of Engine Knock
Decrease Cranking Compression
Decrease Effective Compression
Idle Vacuum is Increased
Idle Quality Improves
Open Valve-Overlap Decreases
Closed Valve-Overlap Decreases
Natural EGR Effect is Reduced
Increases Piston-to-valve clearance

OMR's tutorial is an excellent resource for those who are interested in learning to degree their own cams.

Your probly not going to notice the power band peak actually dropped by changing centers. It's like this. You can set up for peak torque and hp with 110lc's, then move them down and bam now you have more torque across the board. Most likely more peak torque as well as hp. The thing is when cam timing on the intake is late it will start pulling on top but it doesn't really help you as far as more power more speed cuz it takes an hour to wind up and by that time everones parked and eating lunch BEER! What you lose on bottom can never be regained at the top, usually you lose torque, hp, and enough at that to set u back farther than you really wanted to go across the board. Dale used to win drag races in the stock class by setting cam timing to gain torque. And that would be for getting the pig off the line and moving down the track, to cross the finish line in time for pictures and ice cream. I'll bet if u set centers down on the engine you'll be popping the front tire off the ground like it never did before. You have nothing to lose and everthing you wanted to gain. I know there are alot of people on this board that set up like said and will likely swear by it too. Omars bike is set up like that. Plummen, Larry, that's their preferance. Larry sets up for what the equipment will allow for power all the way to the moon though. You have to realize by advancing the intake cam on a set with slightly longer duration your getting a little more top hence the longer duration. A head set up with a good valve job and maybe some mild port work will show much improvement over stock performance, and hey whats so bad about that? It's all about increasing volumetric efficiency using the existing parts. Whatever way that can be done it's what you do. And that includes throwing the peak numbers and rpms out the door. There is no sense in trying to make power at high rpm without much compression, this an that and the other factors that matter as well. A lighter crank is only that. CHARGE the cylinders and THEN it will spin up fast. Otherwise the engine doesn't know what the crank weighs.

I say go for low end torque. set the lc to lower #’s , keep the intake track small with high velocity, small carbs, and have some fun.
lets be realistic though, u are not going to feel a really big dif with a lc change alone. but if u want to learn about cam degreeing, what a great opportunity to try it booth ways, and feel the dif..
u already had a killer zx10, so this old kz is going to be a big disappointment in the power department. so u may as well build it for what it was meant to be, a low end torque machine. that is what makes it a very dif animal than the zx10.

Once again Mark, you nailed it. But then we have already discussed at length what my goals are for this project. I will leave them straight up at 110* to start, and then I may play around at a later point. I like the idea of a torque monster to compliment my screamer. I couldn't match the top end of the zx without some major power adders anyway. Oh yeah, BTW I still have the zx10. It will be an interesting comparison.

I don't build engines targeted for only top end performance as was suggested. That's hogwash.

I'm a great advocate of short duration camshafts in combination with a good flowing head, compression and reasonably sized carburetors. I've preached that for several years on here.

You've never seen any post by me telling anybody to put in any cam with more duration that 252@ .050 lift for a street motor.

The cams I use most frequently are:

CM Z1 or Z2 grinds

Web 118 Grinds for 1015 motors with 29's and street heads.

Web 483 grind .395 / 242@ .050. also for small street motors with good head and proper size carburetors.

1135 J motors run 6.18 1/8th mile time after time with compression, 38 Trons and GPz11 cams.

I don't get it why people hang on to the notion that big carbs and big cams are needed for street bikes....just ain't so :kiss:

larrycavan wrote:

I don't build engines targeted for only top end performance as was suggested. That's hogwash.

I'm a great advocate of short duration camshafts in combination with a good flowing head, compression and reasonably sized carburetors. I've preached that for several years on here.

You've never seen any post by me telling anybody to put in any cam with more duration that 252@ .050 lift for a street motor.

The cams I use most frequently are:

CM Z1 or Z2 grinds

Web 118 Grinds for 1015 motors with 29's and street heads.

Web 483 grind .395 / 242@ .050. also for small street motors with good head and proper size carburetors.

1135 J motors run 6.18 1/8th mile time after time with compression, 38 Trons and GPz11 cams.

I don't get it why people hang on to the notion that big carbs and big cams are needed for street bikes....just ain't so :kiss:

word! :laugh: