TZR125 4DL
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Cylinder leg changing's

TZR125 Track Bike > Cylinder/Head Changing's
Another step that can be done before going to porting, is to change the skirts off the cylinder.
There are two options
1) Go SP like (SUGO also)
2) Change the skirts so the flow is more bend towards the ports
Before I decide, like to investigate what is the best solution
Her you see a SP cylinder mounted.
No skirts visible
A close up
Giving a huge flow
Here you see a oem cylinder fitted.
The skirt is blocking
A close up
The flow is somewhat disturbed by the skirt
You can see the difference clearly
Left OEM right SP
Here a example of changed skirts.
The rounding is there to push/bend the flow towards the ports.
The most logical step would be to bend the flow, you see it the most.
But the SP mod is very interesting to.
Currently investigating what to do

Update 18-10-2017

Have started with the leg project.
Decided to remove them complete because that would be the most interesting thing to try.
The SP cylinder have it also the SUGO cylinders have it.
So way not me....

This is how the piston looks, did not clean it at all.
No changes made here
A look inside.
Have left the head on, so no changes there either.
Her I started, made some quick marks
And just starting cutting the legs away
Here both are cut down
Made everything smooth, and flowed the end a bid towards to ports
That is all I did
A Picture before

A picture after.

Of course the skirts off the piston is there when the ports are opening
Giving the flow a certain direction to the transfers
Removed the Wrap from the exhaust.
Turns out that this is not a good idea
And she is running again
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