Mikunis won't idle down

Ok, had the intake cam out; the stamping is this:

webcam
1 0
1 0
189 with the live center in the middle of all of that


webcam
1 0
1 0
189

wow, its listed in the current catalog:


lift ad duration duration at .050 grind hard weld

.400/.400 290/290 254/254 189 60-191

excellent mid and upper end performance for road race engines Requires exhaust system, high compression piston and performance valve spring kit

too bizarre

Ah, now we know whats the grind.
So as I can only go from my experience, which would be Autos, that sounds like with that much Duration there would be poor Idle quality.
Get Web to send you the Card that has the full cam profile, so you know the opening and closing degrees. Now if as I stated earlier, the IN Cam either was set or ended up retarded, this will cause the reversion in the intake tract at lower RPM. While probably great for high RPM road racing, not real good for trying to Idle at a stop light.
So from my experience with some big profile cams. Installing them with the degree set up is best. Now those say V8 cams would have the Lobe Center Line ground into the profile, No changing it. But you have dual cams so you can play with that, please read this from Webb: www.webcamshafts.com/mobile/degreeing.html
So a smaller Lobe center is probably what I would suggest, advancing the IN Cam to gain that. Being careful to not cause interference.
Once that is done see how it runs. But I find changing the Ignition advance curve would also be a good thing. Shorten the curve, and increase the Initial advance setting from the stock 10 degrees to more like 16-18. Still keeping the Total advance to around 36-38 degrees. Those road racers may have played with the advance some already, or drag racers might remove the springs altogether. This would just give full advance as soon as it runs, then just set it where it makes the most torque. Knowing the Cranking Pressure of the cylinders would help with timing suggestions and octane ratings etc.
Anyway getting the Cams dialed in is something you will have to do, and follow Webbs instructions, it should be a step by step. Then once you've done it, then it will make sense and seem easy.

Also I don't see where you're located in your profile? Tell all the nice KZ members where you and your Cold Beer is at. Someone might have a cam degree set up close to your area?

still seems odd that it is worse when warm. sounds like carbs still.
mine idles fine at 1200rpm,with 260 duration, .425 lift.

well I advanced both cams a tooth, 4 crankshaft degrees, and it still does the hangup , so I expect motorhead that you are correct, and I'll have to degree them in.

Mark in my experience with cars, bigger displacement means more tolerance of lift and duration.

I'm in Clinton Iowa, lol about as far east as you can get and not get wet. I am told I have access to a degree wheel and the appropriate dial indicators and stands, so I expect thats covered, knowing what I'm doing is another story.

Ed

LMAO I gotta prof read before I submit, Clinton is a river town on the Mississippi to clarify gettin wet.

Still hanging with the cams advanced 1 tooth. Both cams? Wouldn't have a set of stockers to chuck in there? If it is in the carbs then it would still hang with stock cams, right?
I believe your right on saying big engines can take more cam. Lot of cylinder to fill.
This is what keeps playing in my head. The slides are set for an Idle speed, do to the lower signal, they are higher than normal. A quick measurement under the front of one to find where they are at, and someone kind soul like Mark to see his setting. May find out I'm reasonably close to my thinking, that the fuel is being pulled from the Needle circuit once warmed.
Ever run a lopey cam with a Holley? They can suffer from the idle circuit signal being lost due to the Throttle being open to far, un covering the transition slots. Sometimes drilling a small hole in the butterfly will let the Idle adjustment get signal, because you then can back out the speed screw.
Its good you have access to the gear. What about the Center Chain Guide that's in the Valve cover? Also the cam card from Webb, giving you the correct opening and closing degrees?

here is a procedure that OMR put together . its not very dificult to do.
i would try to use smaller rather than larger lobe center #'s. if u have enough valve clearance. this would give u more bottom end. but first try to get the proper lobe centers from web.

MOTORCYCLE CAM DEGREEING FOR ZOMBIES

kzrider.com/filebase/cat_view/231-not-model-specific?start=40

Got the cam card from Web, the factory 750 manual called for .003 to .005 valve lash, the cam card calls for .006, so we are bettin the valves weren't fully closing and that was causing the rpm hangup.

Regardless , reshimming is the next step , unfortuneately it'll be the beginning of next week before we get to it.

Cudos to the people at web camshaft, the gal that took the call was very helpful and had no problem emailing me the cam card; even asked me to let them know what was wrong. The engine could have been shimmed like this for yrs. Pullin a sled in a lawn tractor pull you fire hook to the sled mash it and go, all over in under 2 minutes in most cases. I sure hope this solves the problem. When I find out I'll let ya know.

I got MOTORCYCLE CAM DEGREEING FOR ZOMBIES when I started suspecting the cam timing. You would not believe the amount of time I spent scouring forums about the RS carbs, and then about cam timing for these bikes, just wish I'd had the cam card back then. Just for the record, when the engine was hung up at 3-5k when I stopped it the carbs were ice cold, so there was some major air pullin goin on .Mark , you, MH and Patton are tops in my book. I have to say I'm learnin a lot just goin thru this. Heck everyone here has been great.

I'll tell you about a Crower Cam I had In my small block Chev.
Solid roller, stud girdles etc. Card said .026" Valve lash, always sounded like a lot. Even some noise through everything else. So I play with that setting, I could go to .024" and thats it. Anymore and the power would change for the worse. But it would be a lot quieter. Anyway if that card says .006" I would do it before going with stock setting. You got to love a good Cam grinder, always helpful and very knowledgeable.

You should have seen some of the crazy stuff that got built across the street when the guy who went thru my engine lived there. He had a 10 second KZ 1000 bike for the strip, built a 1200 cc prostreet bike , one piece fiberglass body, stretched home made swing arm, 10 inch Mickey Thompsen street slick on the 4th car tire bike rim made by some company( don't remember who). air shifted with a regenerative onboard compressor, didn't corner worth a dam but great straightlinin and ya didn't need a kickstand when ya parked it. One other friend had a 1600cc kaw strip bike, had it in the garage doin bleach burnouts. Yeah the cops were regular visitors there, but we always seemed to have good timing and never got caught for disturbing the peace. He built more then a few drag cars there too. Now he builds for others on the side and pulls lawn tractor for fun. Plenty of good memories from there.