Boring a 66mm cylinder does not add cc's equal to the bore oversize in thousandths of an inch (despite the overwhelming belief by the uninitiated that it does). Boring to a 265cc engine requires a 74mm piston and a +4mm stroker crank (actually, that only gets you to ~262.3cc's but we'll call that a 265). Obviously, you cannot bore out to a 74mm piston, an entire new (quite different) sleeve has to be fitting into the stock aluminum cylinder leaving DANGEROUSLY little material there to constrain that monster...
new here i got a fast blaster!
- Thread starter fastblast2
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Boring a 66mm cylinder does not add cc's equal to the bore oversize in thousandths of an inch (despite the overwhelming belief by the uninitiated that it does). Boring to a 265cc engine requires a 74mm piston and a +4mm stroker crank (actually, that only gets you to ~262.3cc's but we'll call that a 265). Obviously, you cannot bore out to a 74mm piston, an entire new (quite different) sleeve has to be fitting into the stock aluminum cylinder leaving DANGEROUSLY little material there to constrain that monster...
No, it would be MUCH more than that. More like a 2.65" overbore, which is physically impossible.
A stock blaster cylinder can't go anything over .090" bore, because there wouldn't be much of a sleeve left.
He's either bullshitting us, or mistaking it for a 265cc HJR Big Bore Kit, which haven't been made for YEARS. The last KNOWN 265 BBK was HJR's blaster, which just recently blew a cylinder in half, and is no longer in use.
And of course, James beat me to it
Welcome to the forum! Pics are needed
Ahh good info.. I agree and I see the mistake in people thinking bore is directly affects cc's. i have been reading up on this alot on here and i was comparing to that displacement chart. thats why i said .065 or even .070 bore and him thinkin its a 265cc. haha triple 2.65" bore that would be out in the cooling fins....
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NO, NO, NO, if it is a true Trinity 265 then its not a stroker kit it has a 75mm bore on its first piston with a 57mm stroke and its a 252cc but on its last bore at 77mm its a 265cc.. And YES the 265 sleeve can be bored out to 77mm because the sleeve is so big the case has to be bored for the sleeve to fit in it..
Blaner
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i didnt want to bring it up in respect to his possible mistake, but now that its out there i think he has to answer to sort this out fast!!
Either way you gain it (bore or stroke) you can't do it with a stock engine, there has to be a replacement sleeve dropped in and it's not laughing matter either way...
I was under the impression that the Trinity kits used a kawasaki jetski piston which, I believed, was a 74mm ("stock" bore) and a stroker. I had heard that the true 265cc wasn't possible without taking it to the last bore.
I'd be interested in tearing down and looking at the T265 if it does in fact use stock stroke. The amount of material that would have to be removed to get the port areas needed without making the timing silly doesn't seem to add up in my mind.
not to pick. but why would you have to run silly port timing with a great big 77mm bore? i assume you were reffering to port timing, correct?
The outside diameter of the cylinder (area where the transfer ports pass) is a given size and limited in ability to flow.
Once you take the sleeve out to where a 77mm piston can fit inside it, it doesn't leave much room around it for things to happen.
At higher rpm's (which a stock stroke crank would be well suited for) you need more port time area (so either area or timing to get a given amount of volume) to be able to flush the cylinder. Because the amount of volume that can pass through the now restricted transfers is limited, you'd need the ports open longer OR much larger to reduce restriction on top.
I think that a blaster cylinder would be better suited for a smaller piston with a longer stroke than a much larger piston with stock stroke. For a given displacement, the larger bore hampers the port layout more.
I like the color scheme. So can ya get close pics of motor setup, all the bling?? Oh and do you own the shop?
can i call bullshit? you post one pic of a nice blaster and its been cropped to sh*t where ya can't even see all of it. also, looks like that's in a motorsports shop or something.
more pics or i don't friggin' believe it yours for a second...
also, that looks to be a CPI big bore pipe.
more pics or i don't friggin' believe it yours for a second...
also, that looks to be a CPI big bore pipe.
Are you sayin you'd rather have a detailed description of piston shaving than a cell pic from a motorsport shop? Oh, suspicious minds ... LOL ... burp I just like lookin at nice Blasters ... keep the pics coming.
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