IN THE SLEEVE / CYLINDER JUG,,, THE EXAUST PORT ,,,,SHOULD THE SIDES / RUNNER BE SQUARE TO THE DIA OF THE BORE/CENTER LINE OF BORE ?? OR DO THE SIDE OF THE PORT HAVE A ANGLE TO THE CENTER LINE OF BORE OR THE SIDE WALL OF THE SLEEVE ?? HOPE SOME ONE CAN UNDER STAND WHAT I AM LOOK FOR ?? ALSO 2ND PART OF QUESTION ::::: THE EXAUST PORT LOOKS TO BE A STRECHED OUT D SHAPE ;;;STRAIGHT FLAT ON THE BOTTOM WITH SLIGHT RADIUS IN THE CORNERS TO WHERE THE PORT GOES UP TO THE DIRTECTION OF THE HEAD,,THAN HAS LIKE A 3/16 RADIUS MAYBE MORE ;; AND THE TOP ROOF IS A ARCH SHAPE ;;AFTER ALL THAT WHAT SHAPE IS THE PORT TO BE OR LOOK LIKE ,,,HELP THANKS
STEVE

 

The bottom of the port should be straight line and be right at the top edge of the piston at bottom dead center. The top edge and curved roof of the port is correct. On our sand drag minis we change that shape to a more squared out roof but you will lose bottomend power very badly and have a very narrow power range. For most all applications your roof shape as you described is perfect unless strictly for dunes or loose sand dragracing. The taiwanese and chinese motors are usually way off and need port corrections top, bottom,width, and angle. The top of the transfer and exhaust port height or "port timing" is the most important factor to making huge power gains. Your post said LT80 but your signature lists an eton 50. The lt80 has an ok cylinder but the eton would need a little more port work to be really fast. I'm sure LT 80 or others will add their take on this as well. Hope this helps. FastDad

 

THAKS FOR THE IMFO ,,
STILL WAS TRYING TO FIG OUT:: ANGLE THE SIDE WALLS OF THE EXAUST PORT NEED TO BE TO THE CYLINDER BORE WALL/OR DIA.
ANY IMFO ON THIS PART
THANKS AGAIN STEVE

 

Pm me your email address if you want I have a digital pic of a ported/corrected cylinder on a pred 90 cylinder and a pic or 2 of a ported lt 80 cyl. The shape you have is probably right, straight or slightly curved line at the bottom then a slightly rounded roof like an arch. I think you have the correct shape as you described dont change it. Its the same shape as it was from the factory. I believe the stock ones are pretty much just like an oval shape dont worry about the shape its fine for most all applications. The port size of the exhaust port on all the minis is fairly small and should only be changed if you know what you are doing and have degreed out the ports otherwise let someone else do it for you or it will run like crap. If you are set on doing it yourself you will need to give more info like for trails, duneing, racing, drags etc. Otherwise send it to someone that'll do it for you and give you other support like clutching, head mods etc. Lt 80 would probably help you out with it.

 

Your cylinder is stock (the best I can tell). Nothing wrong.
Whatcha wondering about? Having a problem?



Oh yea,, SLAP THAT CAPS BUTTON!! Using caps is considered yelling and your hurting my ears. HAHAHAHA [img]i/expressions/face-icon-small-smile.gif[/img]