Should I chamfer ports after honing?

[Nicholas]

Hi All,
Armed with too much theory and not enough experience....

I read in “Two Stroke Performance Tuning” by A.Graham Bell that you should always chamfer your ports after re-boring and even honing.

So I have just honed my barrels getting them ready for my new rings and think I should follow the advice, but when I looked up the bill of materials it looked like expensive electric or air tools.

Do I really need to invest in these tools?

He suggested simple ¼” chainsaw file and then finish off with a silicon carbide stone… that sounds OK, but looking online I see others saying die grinders and air powered tools, although they also seem to be the ones selling the stuff…

He also recommended dressing the rings… I guess this all makes sense, just wondered if I really needed the expensive tools.

Thanks!

P.S. I am also going with the gasket sealant advice. Is the permatex no 3 stuff suitable/overkill?

[tz375]

It's always a good idea to lightly chamfer the ports even after a light hone. You don't need any power tools though. Just get a round stone or even a round file.

I wouldn't go near rings with any sort of tool - hand or power. Just measure the gap and if OK, fit and forget.

[Nicholas]

It's always a good idea to lightly chamfer the ports even after a light hone. You don't need any power tools though. Just get a round stone or even a round file.

I wouldn't go near rings with any sort of tool - hand or power. Just measure the gap and if OK, fit and forget.

Excellent, thanks for the advice. Use a file to take the edge off the ports.

He also recommended chamfering the piston skirts about 2mm as this would allow for more oil to stick to the sides of the barrel and make its way on top of the piston. So better cooling and compression, I just don’t want to throw off the balance or open up the exhaust port.

Also, I was going to use a gasket sealants. Do you think it is worthwhile using permatex no 3 for the head and Permatex High Temp RTV for the exhuast flange?

[ja-moo]

If you see and feel a sharp edge, then yes, you should chamfer. The HB here has some cool curved files, and they are cheap! Many don't do the vertical parts of the ports, but flow doesn't like sharp edges, so do them also.

A lot depends on how much you honed. Re-honing for new rings is literally only 5 or 6 up and down passes. You are just removing any glaze and re-scratching the surface.

[tz375]

The top edge of the crown should be left alone. I wouldn't bother with chamfering the bottom of the skirt.

As Ja-Moo mentioned, it all comes down to whether there's a sharp edge after honing. If there is it has to go

[Suzukidave]

I dont think any sealant is needed on the head gasket or exhaust gasket , for the engine case gaskets i like to just wipe them down on both sides with a coat of plain old grease , they come off a lot easier if you open the engine again too . For the case surfaces without a gasket go to the motorcycle shop or online and get some yamabond #4 .