I bought a new piston and had my cylinder bored and it says something in the piston instructions about drilling holes for the exhaust bridge. Do I need to do this and if so what do y'all recommend? Thanks
Drill holes in new piston
- Thread starter Jeffery5568
- Start date
DO NOT DRILL ANY HOLES!
Never heard of such a thing, Can ya take a pic of the instructions and post it< if ya can't figure out how to post it email to sliperhead@netzero.net , I'll post it for ya!>
Blaner
Your Friendly South African Ambassador
blasters do not have a bridged exhaust port. therefore you do not need to drill holes.
These instruction, i have seen on the wiseco installation pamphlet. some bigger 2 strokes have a bridges exhaust to help reduce ring expansion into the port on each stroke, naturally, due to heat etc, this bridge receives very little oil, so they do suggest you drill holes in the piston to allow oil to get to the bridge easier.
Bottom line - not applicable to the blaster. dont worry about it
These instruction, i have seen on the wiseco installation pamphlet. some bigger 2 strokes have a bridges exhaust to help reduce ring expansion into the port on each stroke, naturally, due to heat etc, this bridge receives very little oil, so they do suggest you drill holes in the piston to allow oil to get to the bridge easier.
Bottom line - not applicable to the blaster. dont worry about it
Here is the pic, sorry so late---
It won't let me resize it if i do ya can't read it, But AWK hit the nail on the head!
It won't let me resize it if i do ya can't read it, But AWK hit the nail on the head!
The little holes let a bit of air and oil mixture out to cool and lube the bridge, mainly to save life of the ring and keep the bridge from overheating and cracking.
I've done it to bridged motors before. Without the lube hole it often wears a groove in the ring.
On motors with side exhaust ports or the 3 port exhaust it might be a good way to keep the exhaust side of the cylinder and the piston cool.
You would drill the holes on either side of the main exhaust port.
I've done it to bridged motors before. Without the lube hole it often wears a groove in the ring.
On motors with side exhaust ports or the 3 port exhaust it might be a good way to keep the exhaust side of the cylinder and the piston cool.
You would drill the holes on either side of the main exhaust port.
hmmmm, wonder why none of our "triple exh. port" promoters on here never thought to try that ???
whos to say they havent?
lol not all secrets get talked about in the open forum so they can be copied. i could show off some amazing pics of my piston but im not going to lol 
yep he did nail the instructions say and i quote "If the cylinder has and exhaust bridge the piston should contain lubrication holes on the skirt where it contacts the exhaust bridge."
whos to say they havent?
Don't be letting out any of them slotek secrets.lol.
only reason for comments like this is jealousy, lmao!
. and dont worry i wont, remember the "top secret" pics i posted of the portwork? hahahha I:Ionly reason for comments like this is jealousy, lmao!
That was my spell check screwing up again.
whos to say they havent?
someone has you believing boost/finger porting pistons is a secret, LOL !!!
trinity racing had been offering them for years,
although they were a reliability issue, but who cares about that ?
and theres even an old thread on e2s about them
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So here's the deal. The generic instructions from Wiseco pertain to cylinders with an exhaust bridge. Blasters don't have one ( at least not yet ) so don't worry about drilling holes in the piston. Our friends in Japan found that they could make the exhaust port wider if they cast a bridge into the exhaust port of the cylinder. It works but the bridge is so thin that the hot exhaust gasses make it bulge back into the cylinder. The additional holes in the piston provide additional lubricant to keep the piston from seizing where it contacts the bridge. The bridge in the cylinder also needs to be relieved a couple of thousands after honing to keep everything from getting locked up. I don't know anything about drilling holes anywhere else in the piston for lubrication purposes. I do know that none of the pro MX boys are doing it or ever did.
