Porting and Polishing

[esr250r86]

What does porting and polishing do to your bike? Does it make it alot faster and would it still be reliable? Thanks.:)

[250r4life]

well both questions depend on if the guy doing the porting and polishing knows what he is doing or not...

[TampaBoy813]

Originally posted by esr250r86
What does porting and polishing do to your bike? Does it make it alot faster and would it still be reliable? Thanks.:) porting opens the airway up and makes for =more air...polishing makes the air flow smooth with out turbulance witch is not always better...

[BLACKeR]

yes porting and polishing will make you engine faster, as long as its done well. get a professional who has a good reputation to do it. you lose some reliability as you do with any mod. but its not significant. if you get a basic MX/XC port there wont be any significant loss in reliability.

[esr250r86]

Ok, thanks for the information. Right now I just sent my cylinder in for a mx port and polish and The guy I gave it to has been working on my motors for some time now and they have all been good. But this would be my first port and polish cylinder hopefully it comes out good and fast. Thanks again.:)

[250r4life]

who did you send it to? im here in az as well

[esr250r86]

I sent it to a friend of ours who works at a local shop in Yuma.:)

[wilkin250r]

If you have "sent your cylinder in", I assume you had it in your hands at one point, and looked at the inside. I also assume that you know the basics of how a 2-stroke works.

The size and shape of the ports on your cylinder walls play a significant role in your power delivery. If you raise the top of the exhaust port, for example, your motor will make more top-end power and want to rev higher. There are lots of things that can be done, raise the exhaust height, widen the exhaust ports, change the transfer and boost port angles, all of which have different effects.

However, there are limits and rules. You can only widen the exhaust ports so much. Also, if you make them wider, you often have to change the shape of the top to keep from catching a piston ring.

Many aspects are also inter-related. If you change the exhaust port height, you also need to alter the transfers, because they have a certain relationship between them.

In a nutshell, this is porting. You take manual metal-working tools, and you actually change the shape and size of your ports. This alters your timing, similar to adding a different camshaft in a 4-stroke motor. You tailor the ports for specific power delivery. More top-end power and higher revs. Or more low-end power and torque.

All of this change in port timing also needs to be coupled with a pipe that will enhance the power characteristics of your new porting. A basic pipe will work still work very well, but your best performance will come from a dedicated porting and pipe combination.