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what is your knowledge with 2t engines ? what tools were you using ? you dont have to be a engineer to get good results with a home made portjob but you do need to have a fair amount of knowledge. and without the proper tools you might as well stick a fork in it. those 2 reasons are why first timers dont succeed. they have almost no knowledge, and theyre using a $25 walmart dremel. the engine doesnt run much better than it did before so they give up. read some books, ask questions, look at pictures, buy a decent set of tools. then youll be headed in the right direction

i probly will unless its 30 and snow. but i think its supposed to be around 55

what does 2 polished pieces have to do with anything ? we are talking about why people polish the exh port. some say it accumulates less carbon. im not convinced though. maybe its a negligable amount less buildup ? carbon collects on the pipe walls and theyre smooth. maybe it has something to do with the wall temperature. i really dont know from what ive seen it takes years for anything to build up in the port anyways, regardless what texture or smoothness is on the wall. by then youll have taken the engine apart several times for a new piston and clean out the port so it dont matter anyways

most people that polish the exh probly do it for the reason they think it reduces carbon buildup. im not convinced though. maybe ask your question on one of the engineering forums but i think a rough surface will transfer heat better. and keep the boundary layer at a minimum ?

if the exh flange is round and the end of the exh port is stepped it should increase the velocity when the exh comes back through the pipe. it was explained to me like if you have a garden hose and put your finger over half of it. what happens well the water squirts out alot faster. i never polish my exh port either.

anybody know much about the stepped exh port ? they were doing it on some of the 250cc mx engines and maybe some of the GP 125cc ? figured somebody may have welded a step into a stock cylinder to see how it ran ? camatv seems like your always trying new stuff. ever give it a thought ?

anybody planning to be there easter in 2 weeks ? ill be there unless snows on the ground. supposed to be around 55 but its probly to far out to say for sure

got a old pile of turd bike that im working on and i need some reeds made. will boyesen make me some or tony dukas ?

hopefully it will blow the fuker up and i wont have to cut grass no more hahahahhhaa

they sell e85 around here. might try some in the lawmower

i was wondering about that also. it makes perfect sense ive seen a few guys that really enlarge the 2 windows and thin out the bridge. like pasi on page 8. i was just wondering if rather than enlarging the windows, maybe you could remove the bridge and get the same amount of area, and youll have the added benefit of the bridge not being in the flow path. but i supppose that leaves a greater risk of piston cracks

has to be a reason nobody cuts out the bridge. maybe it would crack the piston skirt ?

on alot of cylinders i think the bridge is there mainly to add support for the cylinder skirt. plus with the bridge gone you would probly gain as much or more intake area as adding boyesen ports. just a thought i had. by no meens am i a banshee expert. never even had a banshee in my hands actually.

anybody got a set of stock cylinder sitting around to measure the intake port width ? if its around 65% of bore, you should be able to cut out the bridge with no problem. ideally the best design is a intake port with no divider

anyone tried cutting the intake bridge out ?

i dont see anything wrong with a template. if you have the tools and alittle knowledge you should be fine. this place sells em http://www.racelogic.com/

ya i could be wrong. was judging it by what the reed cage bolt pattern looked like from calvins website

i dont have a cheetah but judging from pics ive seen it looks like they use cr500 cage

maybe wang and wiseco rods are one of the same ?

this is just a handfull that i found right off the bat. theres alot more but i dont have time right now to post everything http://www.thumpertalk.com/topic/976853-you-guys-gotta-see-this-blown-up-engine/ http://www.thumpertalk.com/topic/950576-10-hrs-on-weisco-crank/ http://www.thumpertalk.com/topic/941245-first-ride-weisco-crank-failer/ http://www.thumpertalk.com/topic/926519-melted-crank-stuffers-ideas/ http://www.thumpertalk.com/topic/901923-02-rm125-wiseco-crank-fail/

i called a while back and they told me china. maybe theyre in a different factory now. hell i dont know. been well know for alot of failures on other sites with dirtbikes. maybe the banshee version is fine. ill see if i can dig up some pics or links. obviously i dont have time to look for everyhting because it goes back several years

wiseco cranks are junk. made in china. seen alot of em broke on other sites. not specific banshee but dirtbikes like cr250/kx250

i cant speculate who knows what or whatever but i can say about half the reason why i bought porting tools and started doing my own work is because a planet sand sponsor ported one of mine about 5yrs ago. exh roof looked like a banana and the floor was grinded down so far the piston skirt uncovered the port at TDC. fixed the roof myself but to run it ill have to either weld up the floor or stack .060" of gaskets. ya been doing my own stuff 5yrs now and never looked back. fuck all the hacks pretending to be pro shops

nice job pasi. final finish looks good. is it some kind of sanding roll you used ?