Topic: DOES ANYONE DRAG RACE THESE CB750'S ????

[grizzzly]

I HAVE MY FIRST CB750 IT'S A 72 & I LIKE IT BUT I'M GONNA BOBBER IT OUT. JUST NOT ME THE WAY IT IS. I AM PICKING UP A 75 CB750F OR SS (NOT SURE WHICH IT IS) PARTS BIKE, DIRT CHEAP, THAT RUNS & HAS SOME REALLY NICE PARTS ON IT. IT HAS A 4 INTO ONE PIPE, KONI SHOCKS AND SOME OTHER STUFF THAT I WILL PUT ON MY 72. BUT I'M THINKING I MIGHT TRY TO MAKE THE 75 INTO A STREET/STRIP BIKE, REAL LOW & DRAGBIKE LOOKING. I'M NOT LOOKING TO GO 9'S OR AIR SHIFTED OR ANYTHING LIKE THAT, BUT SOMTHING SORTA DRAG RACY, BUT DRIVABLE ON THE STREET. I WILL DRAG RACE IT HARD THOUGH, FULL THROTTLE LAUNCHES ON THE WHEELIE BAR , BUT I WANT TO FOOT SHIFT IT. ANYBODY OUT THERE WANNA GIVE SOME MORE IDEAS ? I WOULD MODIFY THE MOTOR SOME BUT NOT TOO MUCH, YOUR THOUGHTS THE CLUTCH IS SOMETHING I'M NOT SURE OF THOUGH, WOULD HAVE TO HANDLE THE HARD LAUNCHES & DRIVING ON THE STREET. SEND ME SOME PICS OF YOUR BIKES TOO. THANKS, JOHN       

[Sam Green Racing]

Sam.

[MCRider]

Cool, what was the time/speed? Looks like it just turned double digits at the end but I can't make it out. 10 or 11 secs? Fastest i've ever gone was a 12.76. Hope to do better with Phaedrus II.

[Sam Green Racing]

It runs 12.0s with terminals around 112mph.

here's another vid with different pipe and streamlining.

Sam.

[scondon]

 Tell Chris not to pitch that old fairing he doesn't use. I'll pop by and take it to the recyclers for him

[Sam Green Racing]

 

Sam.

[754]

no wheelie bars.. way too much heat & they look silly on a 12 sec bike.

 Stretch the swingarm... and use struts.

 really low gearing(cheaper than engine mods)

 Stiffen your forks, like 40 wt, or strap it.

 Lower it, at least on the track.

[MRieck]

Tell Chris not to pitch that old fairing he doesn't use. I'll pop by and take it to the recyclers for him

I'll bring it home with me Sean and send it to you. It should fit in the carry on.

[Sam Green Racing]

I don't give a toss as long as you keep your hands off the RS

Sam.

[Sam Green Racing]

THE CLUTCH IS SOMETHING I'M NOT SURE OF THOUGH, WOULD HAVE TO HANDLE THE HARD LAUNCHES & DRIVING ON THE STREET. SEND ME SOME PICS OF YOUR BIKES TOO. THANKS, JOHN       

Stock clutch and springs up to now. We have a set of Barnett springs but have not needed to use them yet.

Sam.

[scondon]

Tell Chris not to pitch that old fairing he doesn't use. I'll pop by and take it to the recyclers for him

I'll bring it home with me Sean and send it to you. It should fit in the carry on.

    I'll ride over and install it at your place

[Kev Nemo]

It runs 12.0s with terminals around 112mph.

here's another vid with different pipe and streamlining.

Sam.

Love the sound of the full fair in this vid-what's the exhuast set-up?

[Sam Green Racing]

It's not the Honda you can hear Kev, It's the GSXR in the right lane. (the one that came second )

Sam.

[Kev Nemo]

I'm pretty sure it's the Honda-it doesn't come on til launch. Would be a straight pipe?

[DsKing416]

Port the hell out of the head. You can have 1.8 mm milled off the head deck for way higher compression. Put in some CV carbs, You need to set your gearing so that you are topped out in fourth at the end of the run the more you shift the slower your time. Lengthen your swingarm and set the bike as low to the ground as safely possible. Should shoot straight and turn heads on the street too.

[754]

   1.8 MM...       

[MRieck]

   1.8 MM...       

That is a lot

[754]

I think that would eliminate any "drop in' Piston kits..more machining...

[Old Scrambler]

That's one less camchain link for sure and maybe two!  Assuming stock pistons.  Is that correct for an F2 motor?

[sparty]

I HAVE MY FIRST CB750 IT'S A 72 & I LIKE IT BUT I'M GONNA BOBBER IT OUT. JUST NOT ME THE WAY IT IS. I AM PICKING UP A 75 CB750F OR SS (NOT SURE WHICH IT IS) PARTS BIKE, DIRT CHEAP, THAT RUNS & HAS SOME REALLY NICE PARTS ON IT. IT HAS A 4 INTO ONE PIPE, KONI SHOCKS AND SOME OTHER STUFF THAT I WILL PUT ON MY 72. BUT I'M THINKING I MIGHT TRY TO MAKE THE 75 INTO A STREET/STRIP BIKE, REAL LOW & DRAGBIKE LOOKING. I'M NOT LOOKING TO GO 9'S OR AIR SHIFTED OR ANYTHING LIKE THAT, BUT SOMTHING SORTA DRAG RACY, BUT DRIVABLE ON THE STREET. I WILL DRAG RACE IT HARD THOUGH, FULL THROTTLE LAUNCHES ON THE WHEELIE BAR , BUT I WANT TO FOOT SHIFT IT. ANYBODY OUT THERE WANNA GIVE SOME MORE IDEAS ? I WOULD MODIFY THE MOTOR SOME BUT NOT TOO MUCH, YOUR THOUGHTS THE CLUTCH IS SOMETHING I'M NOT SURE OF THOUGH, WOULD HAVE TO HANDLE THE HARD LAUNCHES & DRIVING ON THE STREET. SEND ME SOME PICS OF YOUR BIKES TOO. THANKS, JOHN       

Yep.  I drag mine.  It is also built for the street, so it serves two purposes.  Fun to drag and ride on the street.  If you are going to drag it be sure the motor is stoutly built or you will be rebuilding it.  I run in the 11s with mine and I am still a rookie on the strip.

Art

[NitroHunter]

Air shifters are wonderful. Your tranny will thank you for using one everytime you power shift...

[DsKing416]

I will double check my measurement for that motor tomorrow with my machinist. A heavy cam degree is also required. But stock pistons, stock gaskets, stock connecting rods. Just barely missing the valves is the key. Big bore power just by shaving the head. He shaved my cb550 now running a 12.2:1 compression ratio.

[bucky katt]

I will double check my measurement for that motor tomorrow with my machinist. A heavy cam degree is also required. But stock pistons, stock gaskets, stock connecting rods. Just barely missing the valves is the key. Big bore power just by shaving the head. He shaved my cb550 now running a 12.2:1 compression ratio.

obviously not street ridden then?

[DsKing416]

No it's my daily driver, it's the bike in my avatar, it screams. I'll get you those numbers in an hour or so. I work for an AMA superbike team so I'm just gonna ask the engine builder. He's at work today.

[MRieck]

I HAVE MY FIRST CB750 IT'S A 72 & I LIKE IT BUT I'M GONNA BOBBER IT OUT. JUST NOT ME THE WAY IT IS. I AM PICKING UP A 75 CB750F OR SS (NOT SURE WHICH IT IS) PARTS BIKE, DIRT CHEAP, THAT RUNS & HAS SOME REALLY NICE PARTS ON IT. IT HAS A 4 INTO ONE PIPE, KONI SHOCKS AND SOME OTHER STUFF THAT I WILL PUT ON MY 72. BUT I'M THINKING I MIGHT TRY TO MAKE THE 75 INTO A STREET/STRIP BIKE, REAL LOW & DRAGBIKE LOOKING. I'M NOT LOOKING TO GO 9'S OR AIR SHIFTED OR ANYTHING LIKE THAT, BUT SOMTHING SORTA DRAG RACY, BUT DRIVABLE ON THE STREET. I WILL DRAG RACE IT HARD THOUGH, FULL THROTTLE LAUNCHES ON THE WHEELIE BAR , BUT I WANT TO FOOT SHIFT IT. ANYBODY OUT THERE WANNA GIVE SOME MORE IDEAS ? I WOULD MODIFY THE MOTOR SOME BUT NOT TOO MUCH, YOUR THOUGHTS THE CLUTCH IS SOMETHING I'M NOT SURE OF THOUGH, WOULD HAVE TO HANDLE THE HARD LAUNCHES & DRIVING ON THE STREET. SEND ME SOME PICS OF YOUR BIKES TOO. THANKS, JOHN       

Yep.  I drag mine.  It is also built for the street, so it serves two purposes.  Fun to drag and ride on the street.  If you are going to drag it be sure the motor is stoutly built or you will be rebuilding it.  I run in the 11s with mine and I am still a rookie on the strip.

Art

How many times have you had it at the strip Art? Also...what was you best mph??

[DsKing416]

So .8mm is the acurate number sorry for the scare. He says any cb750 or cb550 or cb350 can safely go .8mm

[sparty]

I HAVE MY FIRST CB750 IT'S A 72 & I LIKE IT BUT I'M GONNA BOBBER IT OUT. JUST NOT ME THE WAY IT IS. I AM PICKING UP A 75 CB750F OR SS (NOT SURE WHICH IT IS) PARTS BIKE, DIRT CHEAP, THAT RUNS & HAS SOME REALLY NICE PARTS ON IT. IT HAS A 4 INTO ONE PIPE, KONI SHOCKS AND SOME OTHER STUFF THAT I WILL PUT ON MY 72. BUT I'M THINKING I MIGHT TRY TO MAKE THE 75 INTO A STREET/STRIP BIKE, REAL LOW & DRAGBIKE LOOKING. I'M NOT LOOKING TO GO 9'S OR AIR SHIFTED OR ANYTHING LIKE THAT, BUT SOMTHING SORTA DRAG RACY, BUT DRIVABLE ON THE STREET. I WILL DRAG RACE IT HARD THOUGH, FULL THROTTLE LAUNCHES ON THE WHEELIE BAR , BUT I WANT TO FOOT SHIFT IT. ANYBODY OUT THERE WANNA GIVE SOME MORE IDEAS ? I WOULD MODIFY THE MOTOR SOME BUT NOT TOO MUCH, YOUR THOUGHTS THE CLUTCH IS SOMETHING I'M NOT SURE OF THOUGH, WOULD HAVE TO HANDLE THE HARD LAUNCHES & DRIVING ON THE STREET. SEND ME SOME PICS OF YOUR BIKES TOO. THANKS, JOHN       

Yep.  I drag mine.  It is also built for the street, so it serves two purposes.  Fun to drag and ride on the street.  If you are going to drag it be sure the motor is stoutly built or you will be rebuilding it.  I run in the 11s with mine and I am still a rookie on the strip.

Art

How many times have you had it at the strip Art? Also...what was you best mph??

Three times this summer/fall Mike.  I was rained out 5 times.  Two of the three nights the air was heavy and I had similar runs to my first time - high 11.9s.  One of the nights was cool with lower humidity.

1/4 Mile ET:   11.740
1/4 Mile MPH:   120.260
1/8 Mile ET:   7.656
1/8 Mile MPH:   94.700
0-60 Foot ET:   1.895
Air temp:           79 degrees
Rider weight:      154 lbs.

Spun the rear wheel a bit and then it hooked up.  My 60 ft. time hurt me.  Ran it to the rev limiter on every shift.  I ran these numbers with the new tune I put on the bike.  Dropped the needles in the CR carbs and changed the jetting and timing.

Each night it was one run and done because the line was long.  Friday Night open racing gets CROWDED!  Everyone wants to run their motor and it is a mix of cars and bikes.

Art

[turboguzzi]

yo guys

looks like you totally overwhelmed poor grizzzly..... he was only asking for some tips....