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Two Stroke Addiction
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Discussion Starter #1
I just finished this small "home-made" tool, It is intended to get the cubic centimeters my comustion chamber and piston dome have(C.C's), if You are wondering WHY Do I need to know this, It's simple: To "SET" the Compression Ratio(CR) my engine will have.

I got a couple of clear plastic pieces:



Draw a 50 m.m. circle, same as my piston diameter, then cut as close as possible:


 

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Two Stroke Addiction
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Discussion Starter #3

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Two Stroke Addiction
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Discussion Starter #4
Next step is to drill the center of the plastic piece, mount a bolt and set this plastic piece on the lathe:




After some work, You get these ones:

 

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Two Stroke Addiction
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Discussion Starter #5
One of these pieces is gonna be used on the combustion chamber:





The other is gonna be used on the cilinder:



I will share with You how to use this tool at my Engine built thread
 

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But who prays for Satan?
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6,571 Posts
WoW! Mexicano, You ROCK! Can I please please please, see some more pictures of your lathe? That thing looks really nice!

Excellent work, now I understand, you are checking the actual Heads compression ratio, this is really important, especially on the euro bikes, they have many optional sizes for the heads, like .5 .6 .7 .8 etc, that way, just buy a few head inserts (Domes) and you can dial in the squish at the track.

Keep it up! this thread, like all your other threads is Really Cool :cool:


ps

I think we are speaking about "Head-land" area?
 

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Two Stroke Addiction
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654 Posts
Discussion Starter #7 (Edited)
WoW! Mexicano, You ROCK! Can I please please please, see some more pictures of your lathe? That thing looks really nice!

Excellent work, now I understand, you are checking the actual Heads compression ratio, this is really important, especially on the euro bikes, they have many optional sizes for the heads, like .5 .6 .7 .8 etc, that way, just buy a few head inserts (Domes) and you can dial in the squish at the track.

Keep it up! this thread, like all your other threads is Really Cool :cool:


ps

I think we are speaking about "Head-land" area?
Nick:

Thanks for the kind words.

Yes, we are speaking about the head land area.

It is "A MOST" to check for the actuals head CR because if You don't, then you are just "guessing" the CR...this could be a problem and the cause of pinging = hole in your piston/overheating.

This microlathe has ALL the available accesories...all of them inside boxes and hard to pull out to take pics of every attachment...but you can see all the available stuff at their web site(I have all of them), mine has a "Threader" modification and a "Quick Change" tool post, not available with the manufacturer....also there is some CNC stuff for this MicroLathe..which I never got

Attched a couple of pictures.

Regards,
 

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im new to the forum. it was your engine build thread that brought me to the forum mexicano. your posts are so educational i have learnt a few extra things to do to my engine so thank you for that.

i just thought a quicker way to measure the cc of the engine is to have the engine built, set the piston to bdc and then inject a measured amount of fluid through the spark plug hole with the engine upright upto the bottom thread of the spark plug hole and the amount you inject is your cc? is this correct and would maybe only work for the engines with the spark plug in the top of the cylider?

cheers, damo.
 

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Two Stroke Addiction
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654 Posts
Discussion Starter #9
im new to the forum. it was your engine build thread that brought me to the forum mexicano. your posts are so educational i have learnt a few extra things to do to my engine so thank you for that.

i just thought a quicker way to measure the cc of the engine is to have the engine built, set the piston to bdc and then inject a measured amount of fluid through the spark plug hole with the engine upright upto the bottom thread of the spark plug hole and the amount you inject is your cc? is this correct and would maybe only work for the engines with the spark plug in the top of the cylider?

cheers, damo.
Thanks!, I'm glad my post are helpfull for You :)

Yes, You caould do it the way you suggest.

Regards,
 
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