Jump to content

4 mil in trenched cases?


Common24

Recommended Posts

for sure theres some sharp folks on these forums. im not disputing that. but the fore most experts on 2strokes dont reside in the usa ;) .

 

 Haha. Ive noted that sentiment on a few boards alluding to the fact that the USA is behind the times when it comes to 2stroke Tech,,,and that may well be. But! What we are talking about here is a Banshee based motor. ( i know 2stroke theory translates across the board generally

 

Nobody "across the pond" or across ANY pond for that matter can touch the premier US builders when it comes to banshee specific engines....i mean how many aftermarket cyls are designed outside the USA? 

 

That's the only point I'm making with regards the topic here... anyone can easily discredit "theory" such as the link i posted,but when you have guys "theorizing" in that thread who are the creators, and R&D testers of the most popular/powerful aftermarket cylinder designs of all time( for Banshees),,i'd tend to give them a little credit... because honestly in the case if CP Ind he does more than just theorize ,,he actually tests stuff in the real world  through racers and builders.

 

   Side note: I have no vested interest in CP Industries , nor  am i a CP nut-hugger. ( Or PS for that matter) It just seemed somewhat dismissive to simply discredit what some knowledgeable people posted online ( free public knowledge) with a simple " eh, that's just BS" basically .

  But carry on! :)

Link to comment
Share on other sites

Talked to K&T and they didn't recommend it. The charge from the bottom end wouldn't be as great because of the greater volume. Just bought some used cases and had them sent out to be ported and bored to the 72mm. Thanks for the input

 

 

Sent from my iPhone using Tapatalk - now Free

Link to comment
Share on other sites

i didnt say anything was bs. i said from the little bit i read it appeared to be theory and speculation. i work any where from 8 to 16hrs a day. 23 page post is gonna take me more than a 1 hour to read through. maybe somewhere in the 23 pages theres conclusive evidence supporting one way or the other the big vs small crankcase.  i know if i were to design my own engine i wouldnt be trying to force the charge into the cylinder . maybe some builders have a different outlook on this subject.

 

even though the aprillia was a rotary crankcase engine, theres still plenty things we can learn from what theyve done. theres some even newer engine concepts those same people are working on. pretty cool stuff

Link to comment
Share on other sites

this is some stuff written by a guy across the pond ;) . a smart feller indeed. now if my thinking is correct the vforce with its design and thin petals shouldnt need as much pressure drop as standard reed setup

 

"During the transfer of mixture the crankcase pressure drops. The larger the crankcase volume, the smaller that pressure drop will be. That means, a large crankcase delivers its mixture with a higher average pressure, thus with a higher average density. And even if the flow volume were limited by time.area and flow efficiency, a denser mixture means more mixture mass and thus more combustion energy per cycle."

Link to comment
Share on other sites

Think about a ported speaker box. Too big of box = no port velocity = no spl. Piston is the speaker, crankcase is the box, transfers are the port. There is an optimum case size for a given bore size, and transfer size. To big of crankcase would lose you some velocity even given how air flows from high to low pressure. If someone actually set down and did some calculations, I think one could tune the case to the transfer ports.

Link to comment
Share on other sites

Well, apparently we should be sending our stuff overseas because that's where the "foremost 2-stroke" builders are. NOT.

 

That's why EVERY builder over there uses CP products. If they knew more, they'd build their own.

 

What about the UAE crew? They spend tens of thousands of dollars every year on Banshee stuff from where, the USA.

 

The notion that the US doesn't have the best 2-stroke builders is absurd.

 

If you want to go ahead and stick a 4mm crank in 10mm or whatever cases, go ahead. When it runs like fuck you can have registered user help you figure it out.

 

 

 

 

 

Link to comment
Share on other sites

What about the UAE crew? They spend tens of thousands of dollars every year on Banshee stuff from where, the USA.

id bet its more than that. more like hundreds of thousands.

 

i would say that running a 4mill in trenched cases will have no noticable effects to 99% of the banshee owners out there. i broke my stuffed cases on my shifter cart and went back together with stock cases with no noticable change.

Link to comment
Share on other sites

Stolen almost a year ago. an 80 on a sprint course is good for most. you can beat the piss out of it and not get to outa control. a 125 demands respect. anyone who talks of more motor is either on a big track or full of shit. i highly rec owning one at least for 1season. used can be had for 2k. most fun driving i think ive had.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...