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Well I'm bored and found my way into my old Photobucket acount. The old days for me working on quads and dirt bikes. Some big leassons learned in my short time there.


Initially there was a squish band machined into the head.




 

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600 out of an 800

 

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Cool Stuff. I wish I had pictures of some of the stuff I tried back in the late 70's, early 80's. Lot's of learning went on for me back then. With no real guidance, a lot of mistakes were made, but I'm a lot smarter for it. I built almost every head dome shape that came into my head, but I can't say I ever came up with one like that. How did it work out for you? Honestly most of mine were a step backwards, but a couple of them worked out really well, and gave me direction for future stuff. Trial and error. Was that carb one of the ones Dakota perf was doing, or something you did. Nice machine work. Did lots of taper bored carbs back then too. The dirt bike guys really liked them. Hopefully others will add some pictures here.
Tom
 

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Discussion Starter · #6 ·
Tom, This was some of my learning curve too. I don't know a whole lot now but even less back then. I was helping a guy who was trying to get his business off the ground. It was a common household name in certain circles back then but not anymore. He had the swirled chamber and rifled carbs as some of his big selling points. It was actually a lot of fun to do but IMO he took the swirl design too far. We did the carbs and heads in house. Trinity Racing used to do a head design with machined in hash marks on the squish band area back then also.
 

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Discussion Starter · #7 ·
And so did this swirling air effect make a difference on anything?
Well...it seemed to make the piston wash much more uniform and spread out along the circumference of the piston dome. The lack of a squish band IMO hurt it! Between the head design and the carb rifle I think I'll stick with tried and true designs for a while.
 

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You put smaller sleeves in the cylinders to match the stroke to get the 600cc's.
 

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I was wondering about the lack of squish. Everything I tried that didn't have a somewhat conventional squish band, seemed to go backwards. More prone to detonate, and harder on the ring lands. I don't know it those were issues for you on that one. Sure looks cool though.
 

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Discussion Starter · #11 ·
I was wondering about the lack of squish. Everything I tried that didn't have a somewhat conventional squish band, seemed to go backwards. More prone to detonate, and harder on the ring lands. I don't know it those were issues for you on that one. Sure looks cool though.
Never had deto issues or problems with the ring lands coming out. Surprising because he always slotted the snot out of the stator plate to crank the timing up. I don't think I ever seen him with a degree wheel on the motor to check port timing or ignition timing.


Interesting looking stuff but the vortex type combustion chamber is like having the turbo crank mod!
 

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Discussion Starter · #12 ·
A CK3 seat my dad and I worked on
 

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Discussion Starter · #14 ·
You can use a hole saw with decent results. Just grind down the teeth and make sure it's a fairly sharp edge all the way around. We had a special tool similar to that but with a little more depth. The seat came out real nice. We took out what we could on the plastic substrate.
 

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Discussion Starter · #16 ·
Would the seat not seem real squishy after that? Like, to much so for enjoying the ride all day?
This was built for a snow drag sled. When you sat down it compressed the foam even more so you sat lower and the seat was lighter then stock. Hop of the sled and it popped back to shape.
 
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