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I have only 1 reply to that.
:laugh: :laugh: :laugh: :woohoo: :silly: :lol: :laugh:
That was hilarious man. are u in the right business?
I don’t know what u do for a living but i think u should be in entertainment.
By the way , i see u posted at 3:30 am. What the hell are u doing? are u feeding the friggin gremlins?
Thanks for making my day.

Kzz1p.
I think I will start with the 108 lobe centers that are recommended .
I can use davel’s recommended roll on time test, to get a base line. Then I can adjust to 106, 110 and try that.
I wish I could try some dif pipes ,my friend has a couple. But they wont fit without modification due to my wider swing arm.

I'm running a 1200cc with 0.395 webs at 104,5 and 108 LC's. Still standard 28vm's and it has the best torque I ever had. This set up is BIG fun in the mountains. It still runs 10.500 rpm but not so fast when lobes set at 106-108. Nver had reversion troubles.. only a bit pinging because of the high compression (180 psi cold) so I swop to BS34, see what happens

martijn wrote:

I'm running a 1200cc with 0.395 webs at 104,5 and 108 LC's. Still standard 28vm's and it has the best torque I ever had. This set up is BIG fun in the mountains. It still runs 10.500 rpm but not so fast when lobes set at 106-108. Nver had reversion troubles.. only a bit pinging because of the high compression (180 psi cold) so I swop to BS34, see what happens

What is the duration? what was the recomended LC for the cams?
Do u have any head porting done?
You could advance the timeing a bit (start the spark sooner) to try to avoid the ping . What is it set at now? Dana S? stock?
Or you could try a little more overlap on the cams.
Just a thought.

kzz1p wrote:

I would like to see someone post the RC400 definition as listed out of a "RC Engineering catalog" (as per Russ Collins)
I would like to see a copy of that catalog page. Does anyone out there have a Catalog????????????

here you go :laugh:

joe k wrote:

kzz1p wrote:

I would like to see someone post the RC400 definition as listed out of a "RC Engineering catalog" (as per Russ Collins)
I would like to see a copy of that catalog page. Does anyone out there have a Catalog????????????

here you go :laugh:

Thank You Joe! I knew the RC400's were bigger then we were talking about. They have the 310* duration, that is very big for a street bike and most bracket racing bikes.

mark1122 wrote:

davel wrote:


davel wrote:[/
I disagree. Look at duration at 0.030 lift for the following
Web 0.365 lift – duration 262 (This is what I’m running)
APE 0.410 lift – duration 266
APE 0.435 lift – duration 266 (Marks cam)
That cam should provide loads of mid range in a 1200 or 1300cc motor if set up properly. Pulling 5th gear at 3000RPM should be no problem. In fact, it should be scary.

I disagree! By looking at the RC page that Joe k has posted for us. Those RC400's are called "Pro Stock Special" that means very high compression, for very high RPM. When it says hot street I don't think they were talking about everyday riding. Yes people do use them on the street, I have always called them boat achors. I can personally think of better street cams with more useability that would put Marks motor through the roof. Those cams are so big they couldn't pull a sick whore off a toilet at 3,000 rpm's. Back when the 400's came out, everything was based on car technology with fat durations and fat overlap. If you look at most cam catalogs now days, you won't see any pro stock cams with that big of duration or 90* of overlap. You can set them up until the cows come home, but you can't make a silk purse out of a sows ear. Just in case you havn't noticed, the 400's aren't even close to the APE 435's.

U cant go by those #'s. they are taken at a very low lift for sales purposes.
they have 260* of duration and about .424" lift.
@ .050" lift and 108* L/C has a timing of 22*-58* / 58*-22* (44* overlap)

APE 0.435 lift – duration 266 *** @ .030" so it will be less.
APE 0.410 lift – duration 266 ***@.030"

Davel's
Web 0.365 lift – duration 262 (This is what I’m running)
@ ? lift?

Im assuming the duration was measured on the rc cams from the valve opening to closing, not .050 open to .050 from closed. Also with zero clearance between the lifer bucket and cam base circle. This means the duration numbers for the rc cams will be greater, leading one to believe the duration is through the roof on those cams. A.P.E. cam duration measurement does not start until the valve is already .040 off seat and ends .040 before the valve closes, correct me if i'm wrong it may be .030. This calculates to a shorter duration number, and when .005 to .008 of valve clearance is added, it's shorter yet. Just a rough guess: A cam measured with zero valve clearance and from .050 open o to .050 from clsed might have a calculated duration of 260deg, and when the same cam is measured with zero clearance and also from vlave op. to valve cl., it's duration would be closer to 290deg. The best way to find out what you have is to degree the cams you have using the same method that the cam company used when they measured the ones your comparing with. As long as the method you use is the same between any two cams the duration can then be compared. Valve opening numbers and closing numbers may not be the same and this you can adjust so u don't have that NASTY REVERSION! or a FULL SET of bent valves. And by adjusting the intake cam you can regulate the powerband according to whether you want compression and torque or midrange or whatever u like. So for start set lobe centers to manufacturer spec's, then check the opening and closing numbers and go HMMM? By that time the wifes ready for sex too. Never make the mistake of using a pencil for writing, never work without a gremlin beater. Look close at friends faces, you never know who they are. If your Mark. Take a long look in the mirror before you go out to the garage.

Kawasaki stock cams state 280deg. I measured them using zero clearance at the vavle and measurd from the time the valve opened and closed. It came out to 280deg, we know these cams are not high rpm cams. Some performance cams stating 260deg@.040 and say .395lift when measured from vavle op. to valve clsd. will be closer to 280 witch is essentially the same duration as stock or close to it. The only real differance is the performane cam has more lift. When it's all said and done, loge centers set on your new cam, compare the intake opening and closing numbers to see how much earlier they will open and how much later they will close. You will see the duration is longer and the calculation for duration on paper will show this also. Unless u used a pencil.

mark1122 wrote:

U cant go by those #'s. they are taken at a very low lift for sales purposes.
they have 260* of duration and about .424" lift.
@ .050" lift and 108* L/C has a timing of 22*-58* / 58*-22* (44* overlap)

Yes sales numbers are trickie and yes advertised duration and lift are trickie for sales purposes. I will give you that. Being as dumb as I am, I would ask the question: If the RC way was the hot ticket, why didn't everyone copy it?
Why didn't everyone just add alittle more lift and duration to build a bigger and better mouse trap? It looks like everyone else ran the other direction. They went to smaller durations,higher lift and smaller overlap and some went to dual pattern.
Mark it's your bike, you have to ride it. I am just a friend that is saying, hey! theres a better way. I don't give advise, no one ever takes it. I am only trying to advice you.

I measured my opening and closing points when the cam was at .050" lift. this is the way i have been doing my LC's. I add my lash to that # as well. it doesn’t matter if u use .030" or .050" lift for finding LC. U are just finding the mid point.
It gets the cam past the ramp so it is more accurate. There is just too little of movement on the ramp to tell when it starts to open.
Most cam grinders use .040" which is 1mm. but when u read all the dif sales lit. they use smaller lifts to make the cams appear to have more duration than there competitors.
the problem is when u try to compare 2 cam specs that were derived using dif lift point.
I will try using e .030" just to get a comparison #.

kzz1p wrote:

the 400's aren't even close to the APE 435's.

My mistake on the cams. I thought mark was running the APE K435s