Cool Head on SK27

[DaveAZ]

I've got a rc cool head and the install guide, but I've lost the drill and tap.
What is the drill bit and tap size? Do you think I'll have any install problems if I mate the surfaces as close as possible and thermal couple? Thanks

[pedhead7]

You just wasted Your Money. When I had a Cool head, back in the day of Racing Lh's, I only saw an average of a 10 Degree decrease. I used My Fathers little Rayteck*sp Laser. You point the laser on it, and itll tell You Its temp.
Although I gues you Could Try Epoxy, or Some other Glues, Look on Gpn for a article by wimmig about it.

[DaveAZ]

Well, I've had the cool head in my box of extra parts for at least a year. My rc shroud is already cut so I thought I'd just put it on the BBK. It certainly can't hurt, even 10 degrees cooler. I know when you touch it after a run it's hot, so it must be pulling the heat from somewhere.
Yes I've read Will's article and I still have the Arctic Silver. All I really want to know is the drill and tap size. Thanks for your input, but as long as I've got the stuff I might as well use it.
Does anyone know the drill and tap size?

[DaveAZ]

Oh yeah, I've never seen one on a BBK. Could have also been why I was determined to have one on my g2dhp.

[pedhead7]

Holy Crap I Just Looked at Your Avatar.
Is that a Rc cool head on there?
Did You totaly Just ditch the engine Cover, or Did You Trim it?
If it is a Rc Cool head, did It clear the spark Plug or did You drill it out?

[Brooks]

Here is a drill & tap chart. You just need to know what type, metric or inch, and size of bolt you are using. I would assume either a 10-32(inch) or a 5x.8(metric) would be the size. I've never used a Cool Head, so I don't know for sure what size of screw it comes with.

[DaveAZ]

Brooks, thanks for the link. That's some good info I will use.
pedhead7- yes it is a rc coolhead. I cut out the metal g2d engine cover to fit. I had to rotate the coolhead 180 degrees and bore out the hole for the sparkplug. I'm never happy unless I modify something.....

[wimmig02]

You just wasted Your Money. When I had a Cool head, back in the day of Racing Lh's, I only saw an average of a 10 Degree decrease. I used My Fathers little Rayteck*sp Laser. You point the laser on it, and itll tell You Its temp.
Although I gues you Could Try Epoxy, or Some other Glues, Look on Gpn for a article by wimmig about it.

The CoolHead does little to reduce heat on it's on. The actual cooling addition is just a byproduct of adding the coolhead, i.e. expanding the exposed cylinder cooling capacity. Laser temp gauge's well i have never been fond of them because i can never trust them in exposed sunlight (heat radiation from laser die), in the shade is good.

Any thermal epoxy will do the job, my Thermal Coupling articles are based on Arctic Silver and it's associated family of thermal products. They are the only products that actually have small enough particles to fit into the rough squish points.

[kyle@sp]

What, only 10 degrees? Cool heads rock! They aren't a waste of money. They do work. Motor scooter magazine did a full product review and tests on them. After like two laps the motor with the cool head ran 40 degrees cooler. They said that you could even get better results if you sandblasted the cylinder head. Rich at Scooter Pros wouldn't sell it if it didn't work. He is a PRO engine builder and builds some of the smartest and fastest stuff out there. As far as the it only works in the shade idea, you are wrong. Think about it. What is hotter, the sun heating the metal or the gas explosion going on inside the cylinder. The cool head will only cool things down. That is what heat sinks do. Like I said, anything Rich sells is top of the line.

Peace,

Kyle Patterson

[wimmig02]

As far as the it only works in the shade idea, you are wrong. Think about it. What is hotter, the sun heating the metal or the gas explosion going on inside the cylinder. The cool head will only cool things down. That is what heat sinks do. Like I said, anything Rich sells is top of the line.

The CoolHead is a great design (i own 4), and it does it's job well. But to increase it's effect on cooling many people ThermalyCouple it to the cylinder head. I would not run a CoolHead without it coupled. Coupling the head allows it to transfer THAT much more heat body that you will wonder why you never did it before.

It is common understanding that the die found in laser temp readers is adversly affected by the suns heat and A and B ultravoilet rays. Shade readings are understood to be the best consumer grade units can offer.

[pedhead7]

Wimmig02, How much of a decrease did You see thermally coupling it to the cylinder?
kyle@sp, Yea thats all I saw on average, and Yes I did I have a trimmed Shroud on. Im not Flaming at all, But im shure he would sell them, even IF they didnt work. Why do they sell Rocket Keys? They dont really Help at all, nothing even Close to noticing. Hmmmm, when He did His testing, did He change carb settings? Also was the cylinder sandblasted, and Thermaly Coulpled to the Cylinder?

[kyle@sp]

Wimmig02, How much of a decrease did You see thermally coupling it to the cylinder?
kyle@sp, Yea thats all I saw on average, and Yes I did I have a trimmed Shroud on. Im not Flaming at all, But im shure he would sell them, even IF they didnt work. Why do they sell Rocket Keys? They dont really Help at all, nothing even Close to noticing. Hmmmm, when He did His testing, did He change carb settings? Also was the cylinder sandblasted, and Thermaly Coulpled to the Cylinder?

I realize that you aren't flaming, but Rich at Scooter Pros, wouldn't sell anything that didn't really help. Have you tried a rocket key in a lh sport, and not a X-ped? They do help. If you put them in your X-ped or your RC/BB you are advancing the timing too much for the port timing, that is why you don't see any performance gain. They do actually improve power. You have to competely understand all factors in a two-stroke engine and how they work and exist in a co-dependant relationship. This is why if one thing is wrong, it effects the way others things opperate. I honestly can't see Rich selling ANYTHING that doesn't work. 40 degress is alot. Rich is one of the kindest most generous people on the face of the earth. If you have a problem, he will help you. I just can't say enough about his outstanding habits. He will not rip you off. Plus he builds THE FASTEST ENGINES EVER! I have rode a ton of "Top" engine builders engines that don't even compare to Rich's. He doesn't copy others like many other people do. He is a true engine builder. You don't see that much any more. Sorry if I get a little bit upset when I hear stuff about his products, I just know how they work and the source that they come from.

Peace,

Kyle Patterson

[kyle@sp]

I don't think that they epoxied the cool head, and I know they didn't sand blast them either. They didn't adjust the carb setting at all. It was done un biased. It wasn't even done by Rich. It was done by Motorized Scooter Magazine. It was as fair as humanly possible.

[wimmig02]

Wimmig02, How much of a decrease did You see thermally coupling it to the cylinder?

A properly prep'd and instaled thermaly coupled cool head (or any other cooling device) will eclipse the original cooling benifit from the addition of the cool head.

[pedhead7]

Can I get some Numbers Please?