Wiseco Piston Kit

[NaturalNoobie]

Which piston would be better? Why?
Wiseco Piston Kit, Honda TRX300EX 93-04 .040 N/A $79.99
Wiseco Piston Kit, Honda TRX300EX 93-04 .020 N/A $79.99

[400exdad]

It depends on what you want. Do you want to bore it just enough to clean up or add as much cc's as possible. If the cylinder will clean up by just overboring it .020, I would use that... that of course is only the case if it hasn't been bored yet. I'm not sure how many cc's the .020 or .040 will yield, perhaps someone else can post that.... what you probably ought to be looking at more closely is the compression ratio of each piston, or other brands and their compression. The real power will come from higher compression, but you may have to run a better grade of gas for the higher compression. It would probably be wise to run an oil cooler as well if you do consider a higher compression piston too.

To answer your question, it looks like each piston you list is pretty much equal... typically, only one is made for a 1st overbore (.020) and the other for a 2nd overbore (.040).

[HondaMan222]

wiseco is junk, my 416 piston sezed up on me with'en around 30 hours, get a JE or some other brand. just trying to help

[400exdad]

Originally posted by HondaMan222
wiseco is junk, my 416 piston sezed up on me with'en around 30 hours, get a JE or some other brand. just trying to help

While there may be other or better brands out there, Wiseco has been the staple of piston suppliers for years. Most of the time when pistons fail, it is because of incorrect boring, honing, installation or break-in. However, a piston is a man made product and are not perfect. It is possible that Hondaman got a lemon.

On another note, but talking about proper installation, (for novice piston installers) you HAVE to gap your rings correctly for your bore! They are not pre-gapped from the factory like automotive rings typically are....