Is it possible?

[Mosca]

Im still struggling with this 05, does anyone think it is possible that a stock header could be sort of a plug in an otherwise high flowing set-up? Meaning, with a Vitos K&N style filter, airbox lid removed, boyesen carbon fiber reeds (single stage), wiseco 66.5mm piston, STOCK header and PC pipe, could I be flowing too much on the intake side without enough flow on the exhaust side? Like I am feeding the motor lots of fuel/air but the exhaust cant keep up so it gets bottled up and not enough fuel can get in to the cylinder after about 1/4 throttle?

Also, anyone use the single stage carbon fiber boyesen reeds? It seems weird to me that they would use the stock reed flex limiter thingamabobbers, but they didnt come with their own brackets to hold them on. But now I am wondering if they should have brackets instead of the limiters and so they are not allowing enough fuel in.

 

[4cfed]

no. the stock head pipe sucks but your motor isnt sucking enough air to make it not run for crap over 1/4 throttle.. your jetting maybe off.. you should only be at a 250-260 main at most for your filter and no lid, ditch the stock pipe and it will make more power onces its tuned right

 

[Mosca]

no. the stock head pipe sucks but your motor isnt sucking enough air to make it not run for crap over 1/4 throttle.. your jetting maybe off.. you should only be at a 250-260 main at most for your filter and no lid, ditch the stock pipe and it will make more power onces its tuned right

yeah I hear ya, and I think you are right about the jetting being somwhere 250-260, I tried out stock 230 and right now there is a 240 in it, but it doesnt do squat over about 1/4 throttle, I know a 240 is lean for the slight mods, but I feel like it should still run somewhat okay, even though lean. I feel like there is something else at play here other than just jetting, I just cannot for the life of me figure out what.

 

[piezzi]

yeah I hear ya, and I think you are right about the jetting being somwhere 250-260, I tried out stock 230 and right now there is a 240 in it, but it doesnt do squat over about 1/4 throttle, I know a 240 is lean for the slight mods, but I feel like it should still run somewhat okay, even though lean. I feel like there is something else at play here other than just jetting, I just cannot for the life of me figure out what.

Try putting your airbox lid back on and see if it runs better. If so, then you have your answer.

Good luck!

 

[Mosca]

yeah that is the next step, was going to try last night but started raining of course, I may try the stock reeds again as well.

 

[Awk08]

i have had a stock exhaust that broke loose a cone in there, yes there are cast iron restrictor cones in there,
it jammed sideways and was blocking the flow, the only way i figured this out was, i took the pipe off for somthing and it broke free and i could hear it clunking around in there
i'd say look for a good used aftermarket pipe