Piston question

[Tharrell]

I got a piston in today for one of my other projects maybe some of you have seen something like this.
It's a Namura piston for a Blaster 200.
This is the 4th piston we've ordered but this one is different.
It's got higher intake windows, reinforced the inside of the crown, and there's a section of the crown removed on the exhaust side to advance the exhaust.
At first I thought they sent the wrong piston but the box says it's right.
The other boxes said OEM and they did look just like the OEM pistons that came out of the bikes.
My buddy Sam says the old flat track Bultaco guys would put pistons in like these when they needed more top end.
Anybody ever seen or used this trick?

[riverman]

Don't use that junk (Namura) I have friends that have tryed them in thier banshee's and they don't last. Vito's sells power pistons for banshee's I'm not sure about the Blasters but they are cut down the front or exhuast. Just order a Wiseco prolite and you will be happy for a long time. Yes it cost more but is 100 times better.

[kball1313]

Once again the piston posts are back. I know a few different guys that have used em with good results. All things being equal, they make a good piston and i'm not sure why they're sold so cheap.

I'm using em in my buddies cr250 that i'm building for him. Cylinder size and condition are what''s gonna make any piston last.

I've read guys doing a 'top end' job on a plated cyl engine. This usually involves taking apart a dirty engine, not inspecting the bore properly if at all, reassembling it with a fresh dose of dirt in the crankcase and dislodging all kinds of slop from the power valve. One hour later the engine comes to a screeching halt and guess what gets blamed?

I'm not saying that's what you're going to do. But that's a big part of all the product shit talking that infests the forums.

[AlisoBob]

I've read guys doing a 'top end' job on a plated cyl engine. This usually involves taking apart a dirty engine, not inspecting the bore properly if at all, reassembling it with a fresh dose of dirt in the crankcase and dislodging all kinds of slop from the power valve. One hour later the engine comes to a screeching halt and guess what gets blamed?

AKA the "Britincali-Method".

[kball1313]

ahahahaa

Is that the man, the legend? Looks like he's prescribed some serious post ride therapy.

[87CR500Rider]

I ran a Namura piston in my 01' CR125. No issues, but then everything was measured before it went in.

[Tharrell]

Here's the cutout on the crown I was talking about.
The other picture is the intake windows.
These pistons are for the same bike just different sizes.
btw-Sam rubbed the coating off while sizing it for the bore.

[dubious01]

that exhaust relief area is the hottest spot on a piston, I be worried about it buring through, distorting, or distorting the ringland, since its so exposed.

The turbo streetbikes I run are famous for blow torching the exhaust releifs above the exhaust valve ring land, where the crown is thinnest above the rings, causing the ringland to distort, and stick rings.... things quickly deteriorate from there forward....

[Roostius_Maximus]

shes gonna have some topend
theres alot of guys that did that work on the 250s, mainly because they were plated and instead of grinding ports and replating they did the pistons, never heard it was damaging. I know a dude on the ice thats done that trick since his dad taught him how

[dubious01]

oh?
maybe we''ll go completely nuts on Motor #3....
If I don't like it, its only a piston and a jug....

[Tharrell]

Yeah, Sam said it'll have topend but no torque for shit though.
He matched all the ports and polished it up some.
We'll see, Maybe he'll get it put together before I leave wednesday.
He's on the last bore with that jug anyway.
Heck, we have 2 YZ400 engines to go in these Blasters anyway.