NEWS engine " SHOCK"

[Tim_Duggan]

I was deliberately staying out of this thread, but it seems to have changed into a discussion about design concepts on 2 strokes - something I really enjoy reading about / discussing. I'm going to stay away from the brand bashing /defending - quite frankly it's something I'm saddened to see on IW.

When you consider the ramp's purpose I doubt a tight clearance between the rotor and the ramp is really needed at all. It's only there to help guide the inlet charge around a bend (and it could also be argued that it is for case stuffing). I'd imagine that having a stationary ramp with gaps around it should still be better than nothing at all. Even with an offset hole in the rotor for balancing, as long as there is sufficient clearance to prevent rubbing / scuffing the thickest part of the rotor as it passes the ramp.

Having the ramp fixed, as opposed to the plugged rotor would have the mechanical advantage of less rotating mass fixed to the crankpin. if I wanted more rotating weight in an engine, I'd rather have it on the beefy end of the crankshaft - not on the small pin used to drive the drum.

Also, a fixed ramp would maintain the same angle relevant to the crankcase / case passages regardless of inlet position.

 

[Don Ferrette]

Don, define "Thin vs Thick" and quit making analogies.

I never said anywhere it's definitive, just applying theories. Are you bored or something? You started out asking what I think remember? So I'm saying what I think. Geez, you must have cabin fever worse than I do.

 

[Piston1]

LOL, I think you right Don,we need a dose of Nitro and / or more videos of the races we attended last year.

Hang in there,

JOSe

 

[Don Ferrette]

LOL, I think you right Don,we need a dose of Nitro and / or more videos of the races we attended last year.

Hang in there,

JOSe

Thought you were goin' to bed!! Just couldn't wait til morning to read my reply! :lol:

I'm hittin' the sack too, got contractors hittin' my building @ 7am to deal with tomorrow.

 

[Jeff Lutz]

With all this bullshit about which rotor is better, who did what first, I don't see how people can enjoy this hobby, but I do know this- pistons,rods,rotors,cranks, piston ports, big ports, small ports, taper on top of pistons- PLEASE THIS WAS DONE BY SUPER TIGRE 30 "F G" years ago, anyway back to drums, all of these drums ramped with steel, delrin bushed, hollow all the way through don't even compare to the rotor they were inspired off of-The K 90, yes rossi and many others did it before K but the K mounted on a ball bearing is far better than any drum "floating" on oil, with the K drum on a bearing and oil needing to get to that bearing you can't have a trap, you don't need a trap, although I do agree you don't need an area in that direction for fuel to go nor do you need the volume. What does matter is the size of the induction and THE DIRECTION OF THE FUEL FLOW, take the cam 67 GOLD HEAD MOTOR that everyone thinks will not run,I"ll meet anyone at the pond to show them, that engine will run better with the rotor turned upside down

with the fuel coming in the bottom of the case than running it stock! Stevie wonder could look in that engine all tell what's wrong with it in my mind. On all the Mac drum valves ever made, who will bet money you can tell a difference on 1 good clean running outrigger, which rotor will run better on the radar gun, or on the oval course, (which electric eyes would be needed for ovals), if a difference how much? Better yet, Who was the last person to lose a heat race because of which rotor he had in his drum valve? Jeff Lutz

 

[Joe_Knesek]

Why are you surprised? Once a thief, always a thief. We knew this was coming .... <_<

HELLO DON I WAS REAL SUPRIZED WHEN I SAW A CMB PISTON AND SLEEVE ON E-BAY.IF THIS IS THE SUPPOSED NEW STOLEN TECHNOLOGY IVE GOT NEWS FOR EVERYBODY.IVE GOT ROSSI 45'S THAT WERE MODIFIED BY STAN SIMPSON BACK IN 1993,THIRTEEN YEARS AGO.THEY LOOK IDENTICAL WITH THE SLEEVE CUT AND THE PISTON CUTS IN THE SIDE.AS SOON AS I CAN DOWNLOAD PHOTOS ILL SHOW THEM ON THE SITE.STAN LIVED AROUND JACKSONVILLE,FLA.AND WAS DOING THIS TYPE WORK WAY BACK THEN.I WONDER IF SOMEONE MAY HAVE STOLEN HIS IDEAS. LARRY

Larry, in the mid 80s I think half of my income went to Stan building stinking Rossi 45s and CMB 67s! I'd drive down from Richmond every Friday and spend the weekend in his garage whatching him grind away while his dad showed me all of the neat stuff they had been working on. Of course this was BK.

I was running them in RoadRunners and believe me when I tell you they sounded like no other motor on the water. I think John Finch told me he measured one of my 45s at 35k on his audio tach. No wonder I went through 10 in 4 months!.

The 67s had some of the wildest cuts I have ever seen and timing near 200 degrees. You would think the thing had worms boring through it.

I sure miss seeing him at the races.

Don, define "Thin vs Thick" and quit making analogies.

Thick has software residing locally and thin doesn't! :unsure: :unsure: :unsure:

 

[carlnoki]

Just checked the new 45 and here is what i found for timing,,,,,,,,,,,,,,,,,,,,,,

Exhaust: 183

Transfers: 132

Boost: 128

Intake: Opens 155

Closes 57

Head Clearance set by factory at : .010"

Ramp hold screw IS red lock tighted in place.

Comes with a remotely MOUNTED and Servo Adjustible main needle. And YES , this one DOES flow.

Carb Throat Dia.: 11.8mm or .464"

pics going up in the gallery under carlnoki

carl

 

[Nigtmare]

Just checked the new 45 and here is what i found for timing,,,,,,,,,,,,,,,,,,,,,,

Exhaust: 183

Transfers: 132

Boost: 128

Intake: Opens 155

Closes 57

Head Clearance set by factory at : .010"

Ramp hold screw IS red lock tighted in place.

Comes with a remotely MOUNTED and Servo Adjustible main needle. And YES , this one DOES flow.

Carb Throat Dia.: 11.8mm or .464"

pics going up in the gallery under carlnoki

carl

That's good #'s right out of the box :blink: Carl where did you get the Motor from and how much?

Thanks Nick

 

[carlnoki]

Nick;

got it from tidewater.

the prices for all the CMB line have just gone up by the way.

give Sandy a call.

carl

only thing i would probably do is change the closing timeing to 65 ATDC.

carl