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Discussion Starter #21
Time to clean the grittynis out of the stock bearings using my controversial method of stuffing them full of mother's metal polish then spinning them up with compressed air but its to cold to go outside so I'm going to do it with my dremel

After the treatment I rinse them out with dish soap and 409 under the faucet

Then I spray them down with water displacement 40 ( WD 40 )
 

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Please get some new skf bearings and throw the old away馃檹馃檹
 

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I always pull stock bearings out and put them on the Shelf. Keep them as emergency backups. I know if you bought SKF it would totally blow your budget. I think I always buy them for about $14 for the pair.
 

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Discussion Starter #24
I 100% took you guys advice I went to my local bearing supply shop in Spokane Washington the place is called McGuire bearing after talking with them I decided to go with these Romanian bearings the brand name is Koyo and let me tell you these bearings are smooth they feel just as smooth as Tempkin and SKF bearings they are rated at 24k RPM the groove is nice and deep with almost zero play they are 100 fold better than the stock bearings could ever be and the best part is they did not break the bank or my budget and where onley 13$ for both...

The guy at the bearing shop took my stock bearings and threw them away he told me he would not use them not even in a wheelbarrow he said the steel is way too soft and he could not believe that they were inside of an engine 馃槀
 

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Discussion Starter #27
Don't worry after reviewing my notes I quickly realized that my boost Port was not high enough so I remasked my cylinder and raised it up to 2 millimeters
 

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Discussion Starter #30
On your way. Looking good.
It's getting closer the white flag is out the onley thing I have left is lighten up the wrist pin, drilling the window and polishing the top of the piston, modifying that crankshaft counterbalance and then I can put the internals together 馃サ
 

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Cool. Did you widen and raise the ex port? Try filling the transfer duct end curve with metal epoxy and smooth it out, to make the transfer port point more upwards. I think on that 44mm cylinder, I would also grind out the transfer port wall completely. The 2 separate ducts are so small on their own that it probably doesn't give any benefit to have the wall and different port angles.
I wouldn't bother to lighten the wrist pin or any of the reciprocating parts. How you're going to modify the crankshaft?

Make the exhaust port duration 180, adjust base gasket so that you get 0.5-0.7mm squish gap, swap a carbon reed petal, weld up an expansion pipe with about 750mm total length and then lightened clutch shoes and stiffer springs and it should pull hard :D
 

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I agree on most of it, I wouldn't do anything with epoxy on the transfer ports. If anything I would widen the top or base more. Also considering it's a one piece head, you need to raise the transfer ports the same amount as the gasket that is removed. And I know he already put the boost port 1-2 m m above the transfer ports but that would need to be adjusted as well. To get the most out of the raised compression.
 

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Discussion Starter #33
On a one-piece it's best not to raise the exhaust port the compression is the most valuable thing for making power widening the exhaust Port is the best option to compensate for the piston not being able to come all the way down anymore from removing the base gasket.

On a two-piece yes raising the exhaust port is definitely what you want to do you can gain the lost compression back by running a tighter squish and smaller compression dome.

I don't know that raising the transfer ports will get any gains with a boost port technically the cylinder can only be charged with so much fuel mix and then the rest will get pushed out the exhaust port no matter how strong the sonic wave coming back is of course too much thinking is where I get myself into trouble 馃槂 I will definitely pull the cylinder back off map all the ports ( including the boost port ) put it into the computer and see what it says.

On the other hand I do agree that yes the ports definitely should be raised up the thickness of the gasket but then does the boost Port compensate for that enough and then also give the gain I guess only the computer can tell me that.

My friend is talking about helping me build a resistance dyno as soon as the snow melts away I'll be able to go to the junkyard and get the spindle and brake system off of a car to build the dyno out of so I'm kind of waiting for that because I want to actually see the Gain.
 

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You dont 'have to' work the ports but in the two stroke world when you just rtv the head down with no gasket to increase the squish aswell as boost compression you're essentially dropping the transferport the thickness of the lost gasket.
This also drops the boost port aswell as the exhaust port making the transferport opening more constricted at BDC which in turn will shut off fuel slightly earlier as the engine heads towards TDC.

So naturally to compensate you would raise the transferport the regulated thickness and go another thickness to build performance by allowing more fuel to enter the cylinder.
Another thing to touch on is the transferport tops aren't flat, they're angled in a progressive open shut shut open pattern.
Make sure you keep this angle as its very important in making power.
But you can get away without touching any of that.
 

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I would love to see that Dyno. Take a lot of pictures and maybe make a post on it for other people to possibly build one. That would be an awesome idea
 
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