Show us your "Fred Head"

G'day to you all ,
my first Fred head was a twin with compression valve set up on a GT-5 race prep engine beautiful and fast ,full noise and hit the compression lever and bang the neddle's couldnt handle what hit them,

i now have a tightcase 40mm stroke race engine with a special CU RACE HEAD by no other then FRED, wow this is insane looking at the copper in-forcement he has put in this head and only a single plug,

i also have a twin plug tightcase on the back burner for my winter project coming very soon

WARNING FRED HEAD'S ARE VERY ADDICTIVE
 

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http://motorbicycling.com/showthread.php?t=54134

***
Check out my thread and posts at the above link .... Twin plug Fred head with HD Lightning ignition and TWIN ...YES!!-- TWIN COILS !! Works like you would not believe... what ever anyone says about twin plugs NOT workingf better or NOT making a difference don't know what they are talking about... The proof is right in front of you at the link provided in my pics ..on my bike ..and carry'n me down the road !! Fred knows his stuff and has spent countless hours doing his research and machining and testing and re-testing his heads and other products ... Thanks to Fred we all have the opportunity to have some of his sweat and hard work reflect on our motors by installing a Genuine Fred head !!! (especially the twin plug version!!) My best too all who ride and build "motorized bicycles"

** Ride with Pride **

Ron.
 
Hey , i bought the fred head gt-5 top end kit . it says on freds site to -
"Set up the engine so that when the piston is at Top Dead Center, there will be a .010"- .040" clearance between the piston and cylinder head. A tight squish clearance will produce the best combustion efficiency."
Im not sure what exactly this means. Im assuming when piston is at its height when connected to crank? what can i use to measure?
 
I use 1mm solder to check my squish.
Bolt the top end together with gaskets, torque it down, with a length of solder in the spark plug hole and reaching to the edge of the bore, turn the motor over past TDC, check compression of solder with vernier's.
If it does not compress 1mm solder, try 3mm.
Then adjust gaskets/deck jug/shave head to suit.
 
Theon said:
I use 1mm solder to check my squish.
Bolt the top end together with gaskets, torque it down, with a length of solder in the spark plug hole and reaching to the edge of the bore, turn the motor over past TDC, check compression of solder with vernier's.
If it does not comprss 1mm solder, try 3mm.
Then adjust gaskets/deck jug/shave head to suit.
Click to expand...

Alright i think im seeing it. I understand either that i will add gaskets to make the .01-.04 or sand the head or cylinder down. the part im not understanding since i have not much knowledge of engines is the use of the solder i see that we are putting it down through the spark plug hole and ? ill get it i just need something more visible? thanks
 
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The solder will need to go to the edge of the cylinder then you turn the engine over by rolling the bike or turning the magnet, near the side of the head you have a flat band that will compress the solder to indicate how close the piston comes to the head.
 
okay that is clearing it up some. so if i use 1 mm and it doesnt smash te solder go up to 3 then if that doesnt work maybe sand down the head or the cylinder?. if it smashes 1 mm then add some gaskets?
 
That would be inches, one thousandth to four thousandths. Just mic. it with a inch mic or caliper.
 
You don't want to take any of the squish band off of the head if you take off squish area it will reduce the effective combustion. You may have to lap the top of the cylinder to get down to the desired "squish".
 
Blm25super said:
Hey , i bought the fred head gt-5 top end kit . it says on freds site to -
"Set up the engine so that when the piston is at Top Dead Center, there will be a .010"- .040" clearance between the piston and cylinder head. A tight squish clearance will produce the best combustion efficiency."
Im not sure what exactly this means. Im assuming when piston is at its height when connected to crank? what can i use to measure?
Click to expand...


It means you need a gap between the head and the piston of a minimum of 010" and a maximum of 040", this to a; stop the piston hitting the head, no less than 010" and b; a maximum gap of 040" to maintain efficient compression.

I have not looked at a fred head but the term squish is usually a reference to the closed part of the chamber/piston opposite the spark plug that, when the piston approaches TDC, forces the compression towards the the spark plug.

Hope this helps.
 
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This is my Fred Head but it is really Fred's Head......and not very high compression....

It really doesn't compare to the real "Fred Head".....just wanted to show a comparison ;)

The real Fred is a cool guy who travels thousands of miles just to watch people race who are using his heads (and others) and really seems to enjoy what he's doing with his talent!

It was a pleasure meeting Fred and I hope to see him again sometime at the races (or wherever).
 

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