YAMMIEGOD3:16
Active member
RYAN, WILL DO. LIKE I POSTED TO YA, MY RACE BOX LEANED MY CARBERATION OUT ALOT, I HAD TO DROP CLIP, NOT NEEDLES lol TO CURE IT. DYNO WILL TELL FOR SHURE. 3:16 (yammie tony)
Last edited:
Great info, I had wondered about that. Is the swap as simple as just bolting the cylinders and heads on, rejetting carbs and away you go. Although ideal, I can only assume its not that easy. It seems to me that the 750's have a lighter driveline as well, gears and chain are lighter at least(not much, but some). I have heard some people also say that a good welded 750 crank is better than an 800 crank anyways. I am not sure how someone would test that hypothesis accurately but seems an interesting claim.they are a little quicker 2 rev as the 750 crank is lighter.
bufalobob said:tony:
dropping the needles is leaner???
bob
I WAS TOLD THAT WHEN THE VMAX 4 WAS IN ITS HEYDAY AT THE GRASS DRAGS AROUND 1993-1994 YAMAHA WAS ALREADY USEING THIS SET-UP. 8BU CYLINDERS ON 750 LOWER ENDS. ALSO I THINK JUSTINS MONSTER 560 HP VMAX 4 USED A STOCK LOWER END. 3:16 (yammie tony)Rustman said:Great info, I had wondered about that. Is the swap as simple as just bolting the cylinders and heads on, rejetting carbs and away you go. Although ideal, I can only assume its not that easy. It seems to me that the 750's have a lighter driveline as well, gears and chain are lighter at least(not much, but some). I have heard some people also say that a good welded 750 crank is better than an 800 crank anyways. I am not sure how someone would test that hypothesis accurately but seems an interesting claim.
-Rustman
YAMMIEGOD3:16 said:I WAS TOLD THAT WHEN THE VMAX 4 WAS IN ITS HEYDAY AT THE GRASS DRAGS AROUND 1993-1994 YAMAHA WAS ALREADY USEING THIS SET-UP. 8BU CYLINDERS ON 750 LOWER ENDS. ALSO I THINK JUSTINS MONSTER 560 HP VMAX 4 USED A STOCK LOWER END. 3:16 (yammie tony)
Dyno tuning like you said is critical. Whenever you have to close the spark plug gap to make power, you dont have enough spark energy to begin with... I have upgraded all my bikes to MSD. With stock or PVL on methanol I had to run a spark plug gap of .020" with MSD i can run .036" The change was good for 6hp on a 100hp bikebufalobob said:all pipes from the same manufacturer are not created exactly equal, there can be differences. that's why dyno tuning is sooo important.
the same set of pipes can peak @ 8500 or 9000, it just depends on how much heat is in them which is in direct relation to jetting, hood venting, timing, coolant temperature & run time. the hotter the center section temperature the more the power peak slides up. my 800 sxr w/ bender triples peaks @ 8800 & looses 9 h.p. @ 9000 but only has a difference of 2.5 h.p. between 8500 & 8900.
bender & full power perf. trail ported 700 sxr w/ bender triple pipes is around 150 h.p.. they built a race version for a ty member that was 170+ h.p..
the closer the gap the longer the stator lasts. i run .018 - .020 on all my sleds.
bob
kennedy_power said:Whenever you have to close the spark plug gap to make power, you dont have enough spark energy to begin with... I have upgraded all my bikes to MSD. With stock or PVL on methanol I had to run a spark plug gap of .020" with MSD i can run .036" The change was good for 6hp on a 100hp bike
well worth the money