Suck Squeeze Bang Blow

Not exactly, but you can plot a lift curve and work out acceleration rates and changes in acceleration to see when certain values are exceeded to see why a particular cam is harder on valves than another. Valve spring surge is a function of the two springs and their natural harmonics. Couple that info to a lift curve and there's probably a way to calculate it. It's easier to wind the motor open and listen for float :)

Shimming springs is a technique to ajust spring pressures and can change float limits but not by much. A better solution is better springs.
 
Personally I think 'beehive' springs are the best invention in the last several years.
They can't be fitted to everything though
 
teazer said:
Not exactly, but you can plot a lift curve and work out acceleration rates and changes in acceleration to see when certain values are exceeded to see why a particular cam is harder on valves than another. Valve spring surge is a function of the two springs and their natural harmonics. Couple that info to a lift curve and there's probably a way to calculate it. It's easier to wind the motor open and listen for float :)

Shimming springs is a technique to ajust spring pressures and can change float limits but not by much. A better solution is better springs.
Click to expand...
have you tried the beehive springs that crazypj is referring to? Can they be fitted to a cb200? Does the beehive transfer more tension when lift would occur (that is the picture I have in my head)?
 
Pretty sure no-one makes them small enough for CB200 at present, not sure they ever will?
They can cope with higher lift and less clearance between coils, plus they automatically 'ramp up' to higher pressure being variable rate (compared to dual rate)
less chance of standing wave being set up in coils at any rpm engine is capable of (unless it can do 16~30,000 rpm, depending on valve size)
Valve float is determined by spring rate though, at max lift you get max rate
They have been stock in Harley's for a few years, Chevy LS motors and aftermarket for SBC, Ford, big block, etc. May be available for other motors but I haven't done any research
These look interesting though
http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=CTGY&Store_Code=CC&Category_Code=BEE
 
The topic is largely academic though. Your points are likely to stop working before your valves start floating.
 
Points on m y CB72 were good right up to 12,500 right before the big end rollers all failed. It had double springs to follow the reground cam. Raced for years with points back when electronic ignitions were out of reach for us mere mortals.

Old school technique was two springs wound in opposite direction that rubbed against each other to damp out resonance. Norris sold triple springs. The middle one was a flat shaped damper.

Or try a set of custom wound super light titanium spings. Lots of potential solutions including different cam profiles with easier ramps and lower jerk rates (that's the rate of change in acceleration)
 
crazypj said:
Pretty sure no-one makes them small enough for CB200 at present, not sure they ever will?
They can cope with higher lift and less clearance between coils, plus they automatically 'ramp up' to higher pressure being variable rate (compared to dual rate)
less chance of standing wave being set up in coils at any rpm engine is capable of (unless it can do 16~30,000 rpm, depending on valve size)
Valve float is determined by spring rate though, at max lift you get max rate
They have been stock in Harley's for a few years, Chevy LS motors and aftermarket for SBC, Ford, big block, etc. May be available for other motors but I haven't done any research
These look interesting though
http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=CTGY&Store_Code=CC&Category_Code=BEE
Click to expand...
holy beezebullcrap that is a 1000 bucks lol!
 
Suck Squeeze BAng Blow

Subtitled...

Where squish is made better in a semi spherical bathtub after bang and before blow

Or where squish drives her fuel closer to your plug

Or the soliloquy of squish "carbs who needs bigger carbs!"
 
suck, squeeze, bang, blow
we can make your motor go
you want it fast?
We'll make it so
suck squeeze bang blow
Just something I came up with many years ago ;D ;D
 
Suck Squeeze Bang Blow

Dial indicators and accurate STATIC measurements of timing are nice. But you take a cam and crank at 10000 rpm and the actual timing will vary from the torsional flexing of the crank and cam.

No matter how good static timing is, the actual position of the crank and cam can rarely be known.

With the crank itself accelerating and decelerating, cam chain stretching and springing back, the reality is the engine is just a bunch of springs bouncing around. When you look closely at rotational vibration in an engine, you often wonder how it runs at all. And bikes have relatively short cams, usually driven from the center. Take an inline six auto engine and the long crank and cam really get to shaking around.

Even non-reciprocating equipment has lots of torsional vibration. I work on electric and steam driven turbo- machinery. Some of the vibration spectra are downright frightening. You can't believe how much a 6 inch diameter steel shaft can flex.


Sent from planet Earth using mysterious electronic devices and Tapatalk
 
crazypj said:
suck, squeeze, bang, blow
we can make your motor go
you want it fast?
We'll make it so
suck squeeze bang blow
Just something I came up with many years ago ;D ;D
Click to expand...
lol! Great Jingle! I am sure I will get a call from the school counselor. Your son said, "My dad taught it to me!"
 
succhiare spremere botto colpo this deserves some worldwide metatags...and everything sounds great in Italian. :)
 
mydlyfkryzis said:
You can't believe how much a 6 inch diameter steel shaft can flex.
Click to expand...

Can't ? I regularly work on and around Frame 7 General Electric Gas Turbines .
The whole point of this is not so much to take a series snapshots during the cycle but to string all the events together in some sort of understandable fashion . All of this came from trying to reduce harmonics induced by indiscriminate valve openings .

~kop
 
kopcicle said:
Can't ? I regularly work on and around Frame 7 General Electric Gas Turbines .
The whole point of this is not so much to take a series snapshots during the cycle but to string all the events together in some sort of understandable fashion . All of this came from trying to reduce harmonics induced by indiscriminate valve openings .

~kop
Click to expand...
Kop you are really good at closing indiscriminate valve openings ;)
 
Suck Squeeze Bang Blow

kopcicle said:
Can't ? I regularly work on and around Frame 7 General Electric Gas Turbines .
The whole point of this is not so much to take a series snapshots during the cycle but to string all the events together in some sort of understandable fashion . All of this came from trying to reduce harmonics induced by indiscriminate valve openings .

~kop
Click to expand...

My response was for the general audience. Fwiw.


Sent from planet Earth using mysterious electronic devices and Tapatalk
 
I finally managed to read all of the original post (meds made my eyes weird for a long time, could only read parts of it previously)
Suzuki shims come in 0.05mm (0.002") increments not 0.50mm (approx 0.020")
As far as I remember all manufacturers use 0.05mm increments.
Suzuki also have 'odd' sized shims from factory (272, 273, 277, 281, 282,etc)
I had shim sets for Suzuki, Honda, Yamaha and both Kawasaki sizes (before they went to the 6~8mm? shims)
The KZ500/550/650 are great motors but rarely got serviced properly ('too expensive to have cams taken out, etc)
Anyway, as for valve clearance affecting compression, I found +/-0.002" variation in clearance could be as much as 20psi difference in cranking pressure on some motors
That's all for now ;)
 
crazypj said:
Pretty sure no-one makes them small enough for CB200 at present, not sure they ever will?
They can cope with higher lift and less clearance between coils, plus they automatically 'ramp up' to higher pressure being variable rate (compared to dual rate)
less chance of standing wave being set up in coils at any rpm engine is capable of (unless it can do 16~30,000 rpm, depending on valve size)
Valve float is determined by spring rate though, at max lift you get max rate
They have been stock in Harley's for a few years, Chevy LS motors and aftermarket for SBC, Ford, big block, etc. May be available for other motors but I haven't done any research
These look interesting though
http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=CTGY&Store_Code=CC&Category_Code=BEE
Click to expand...
Crazypj these do look interesting and we measured both our stock springs and the racing springs we have from Vintage advantage. I know I am a slow responder but it takes me this long to process but eventually I get there ;)

The od of the stock 200 valve was 21.75mm Vintage advantage is 21.32 and the beehive is 26.94 at the bottom and 25.35 at the top.

What would be your recommendations to make this work?
I am going to post this info on our build string also for easier reference thank you!
 
I think the diameter is going to be a problem, plus the spring rate looks like it's going to be far too high and could pull the valve head off?
 
crazypj said:
I think the diameter is going to be a problem, plus the spring rate looks like it's going to be far too high and could pull the valve head off?
Click to expand...
thank you PJ...cyclex and schumann are selling beehives in a kit for a cb 750. I think you are on to something if you can save 25 grams by getting rid of the inner spring. We will do our homework on spring rates etc and keep looking.
 
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