Author Topic: CB750A Street ET bracket drag bike. A year to build it.  (Read 618264 times)

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Offline Leino

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #600 on: March 03, 2011, 03:31:05 AM »
Sounds like my first trip ever on my CB, almost 11 years ago  ::)
I even phoned the previous owner when I stood at the side of the highway  ;D
Took me a few minutes to figure out nothing was wrong, just ran out of fuel  ;D

My previous bike was a one cylinder 2-stroker, so the fact cylinders dropped out one by one fooled me big time  ::)

Offline Sam Green Racing

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #601 on: March 03, 2011, 04:47:51 AM »
It sounded crisp enough when he was leaving Mike, remember, there is no reverse cone on that exhaust.

Sam. ;)
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Offline Jim F

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #602 on: March 03, 2011, 05:21:22 AM »
We need to change the plugs as they are fouled up pretty bad (Burning off all of the assembly lube plus just checking stuff out while at idle.)

No more leaks and the breaks are holding like no ones business.

lots of work to be done on the carbs and Bill got he tubes from Mike for carb synching. (Thanks so much Mike)

lots of little stuff still to be done but Bill has really charged hard on this project and can finally see some day light
and its not the locomotive heading towards him like he thought a couple of weeks ago

well done Bill..........

I need to call pingel and have a talk and order some stuff for the modifications to the tank

back to Bills this weekend
looking forward to seeing Sam next week
more videos to follow soon
glad all that worked this time as I was expecting to mob in my yard to tar and feather me for not getting the video right

Bill I will call you later today

Jim


« Last Edit: March 03, 2011, 05:22:56 AM by big-jim »
2002 RC51 1000 (SP2)
1983 GS1100EC Suzuki
2002 998 Dukati (Customers Bike)
1992 KTM500 2 stroke
1975 CB750/836 Honda
1978 GS750/840 Suzuki

Offline jweeks

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #603 on: March 03, 2011, 12:57:46 PM »
Not enough ignition advance.

I hope that the take 2 video was on dry carbs. If not, it's not starting soon enough.

I can guess at what the carbs need.... :)

Was powerband smooth or lurchy just above idle?

Any powerbrake attempt?

A good beginning.

               JW

Offline jweeks

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #604 on: March 03, 2011, 04:27:19 PM »
Just one degree before power drops off on the chassis dyno.... ;D

The throttle is a little sluggish. with good gas and a few more degrees (3-5) the idle will come up and the response improve. Of course, they say that as I age, the second thing that goes is my hearing... ;) Unless the cam timing is a ways off, which I'd doubt. Easy to bolt together to the marks.

Mike, what's your ear tell you?

                     JW

Offline Bill/BentON Racing

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #605 on: March 03, 2011, 05:16:40 PM »
Inquisitive minds want to know......like mine.Start up was not dry,fuel was Torco 110,we did powerbrake a couple times.No rear wheel creep.Dyna 2000 on #5,25 degeees advance range,15@ idle,40 @higher rpms.Will check crank sensor.Definitely ran better out than in.Lots of little things to check.Aux tank a little low,but should have still been fine.Will go thru carbs,install sync tubes,install fuel tank with Pingel petcock(they'll be fuel to the carbs) ;)Screws are @ 2 out cause # 2 won't turn out any further,should be 3.25 out(fuel screws).Suspect choke passages and possible gum/trash in fuel mixture screw passages.First thing I'm going to do is drain each bowl and inspect.Jon,it is a good start.You were right,I kept trying to pull in the clutch(doesn't work to well).Want to install idle screw and return spring...just little things.Samauto is coming to a track near you!!!!!! ;D ;D ;D ;D,Bill
BentON Racing Website
OEM Parts | Service | Custom Builds
BentON Racing Facebook
Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
______________________________________
See our latest build 'Captain Marvel' CLICK HERE

Offline jweeks

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #606 on: March 03, 2011, 06:05:56 PM »
     Let me correct my last statement. It needs more initial advance. Don't know the amount of advance in the Dyna curves. I'd trade a little off of the curve for the same amount added initially. We aren't trying to be smooth for the street. The advance curve just gets the bike from idle to 4k on the starting line. We need to do that in the least amount of time that we can. Not looking to increase the total advance, but you really will run quicker with more initial advance. We have about one second to whack the throttle from idle to load the motor against the brake. If you whack the throttle too early (before the christmas tree starts down, you run the risk of increased oil temperatures that may/will slow your run down) The stall speed of the converter should be approached just as you release the rear brake. With the throttle response that I'm hearing, I'm betting that you are leaving around 300 rpm below where it could be launching. That will slow the bike, but not make it less consistent. I'm just trying to get everything out of what you've got.
     What did the tach show when you tried loading the back brake? My guess would be in the 3,500 to 3,700 range? (Motor won't pull to stall speed of the converter with current horsepower level) Was the transition off of idle to midrange a smooth one? Don't think that you'll find much with the carb sync'ing. A little detergent in the gas won't hurt. Fresh plugs at the track will help. Does the Dyna box not give enough spark energy to keep the plugs clean? Plug gaps are ? I like to keep them a little small .025 ish on my bikes.
     With a 10.5 to 1 ratio, you could get away with less octane. Won't make much difference on the time slips, but might affect your wallet a little less. (not counting the VP oxygenated gas that some tracks offer)
     Rear brake holding well is a major engineering success! Minor tweaks from here on out! Sam, what's your reflections on seeing it running? Anticipation increasing?  ;)

                                                                   JW

                                                           

Offline Jim F

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #607 on: March 03, 2011, 07:48:32 PM »
small adjustments from here on out

I static timed the ignition to 35 degrees

this and other things will be changed (Minor adjustments) as we go along

its getting there

thanks to all

Jim
2002 RC51 1000 (SP2)
1983 GS1100EC Suzuki
2002 998 Dukati (Customers Bike)
1992 KTM500 2 stroke
1975 CB750/836 Honda
1978 GS750/840 Suzuki

Offline jweeks

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #608 on: March 03, 2011, 08:06:30 PM »
Can't remember the exact year of the carbs, but this is close:(quote)

Stage 3 Jet Kit  #3116  for 1987 GSXR750

"4. Locate the fuel mixture plug (Fig. B). If you see a screw head
at Fig. B proceed to adjusting procedure. With the DD #5/32 drill bit
provided carefully drill through the plugs. NOTE: The mixture
screw is directly underneath this plug, be ready to pull back on the
drill the instant you break through. Use screw provided to secure
and remove this plug. Carefully turn mixture screws clockwise until
lightly seated, then back out 2 turns."

Float levels according to Bill were 1mm in differences across the 4.

Need the idle screw in place before sync'ing. Without the return spring, it will idle out of gear too high.

Anybody down there got a fuel air meter with sensor? Running unleaded, we could quickly find out how rich we are...

                                         JW

Offline dragracer

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #609 on: March 03, 2011, 09:17:40 PM »
I waited anxiously 2 weekends ago, then again last weekend. Jim, you're killing me with the suspense!! ;D
No more suspense! Samauto runs! Living proof ;D
Hope you enjoy,been a lot of blood,sweat,tears :D,Ok hard work and $$$.Bill Click on the picture,should take you to photobucket video.


Congratulations Sir!!!!!!!!!!!!!!

Offline voodooracer

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #610 on: March 04, 2011, 04:31:39 AM »
 Congrats to all!!! Considering how far away from stock this critter is, I agree, an excellent start! Can't wait to leave the start line side by side heads up, Sam stalled against the converter/rear brake and the Chainsaw on the 2-step @5500, then..........
 Yellow, yellow, ye-GOOOOOOO!!!
 Will be sum fun.
 Keith

Offline Bill/BentON Racing

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #611 on: March 04, 2011, 05:10:55 AM »
 8)Thanks to all.We'll get it right.Bill
BentON Racing Website
OEM Parts | Service | Custom Builds
BentON Racing Facebook
Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
______________________________________
See our latest build 'Captain Marvel' CLICK HERE

Offline Leino

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #612 on: March 04, 2011, 05:25:21 AM »
8)Thanks to all.We'll get it right.Bill
Go Bill, I want to see some powerwheelies  ;D

Offline Sam Green Racing

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #613 on: March 04, 2011, 05:56:08 AM »
    Let me correct my last statement. It needs more initial advance. Don't know the amount of advance in the Dyna curves. I'd trade a little off of the curve for the same amount added initially. We aren't trying to be smooth for the street. The advance curve just gets the bike from idle to 4k on the starting line. We need to do that in the least amount of time that we can. Not looking to increase the total advance, but you really will run quicker with more initial advance. We have about one second to whack the throttle from idle to load the motor against the brake. If you whack the throttle too early (before the christmas tree starts down, you run the risk of increased oil temperatures that may/will slow your run down) The stall speed of the converter should be approached just as you release the rear brake. With the throttle response that I'm hearing, I'm betting that you are leaving around 300 rpm below where it could be launching. That will slow the bike, but not make it less consistent. I'm just trying to get everything out of what you've got.
     What did the tach show when you tried loading the back brake? My guess would be in the 3,500 to 3,700 range? (Motor won't pull to stall speed of the converter with current horsepower level) Was the transition off of idle to midrange a smooth one? Don't think that you'll find much with the carb sync'ing. A little detergent in the gas won't hurt. Fresh plugs at the track will help. Does the Dyna box not give enough spark energy to keep the plugs clean? Plug gaps are ? I like to keep them a little small .025 ish on my bikes.
     With a 10.5 to 1 ratio, you could get away with less octane. Won't make much difference on the time slips, but might affect your wallet a little less. (not counting the VP oxygenated gas that some tracks offer)
     Rear brake holding well is a major engineering success! Minor tweaks from here on out! Sam, what's your reflections on seeing it running? Anticipation increasing?  ;)

                                                                   JW

                                                          

Sam, what's your reflections on seeing it running? Anticipation increasing?  ;)

relief and well increased. ;D ;D ;D can't bloody wait :D :D :D

Sam. ;)
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike

Offline Sam Green Racing

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #614 on: March 04, 2011, 06:02:31 AM »
Congrats to all!!! Considering how far away from stock this critter is, I agree, an excellent start! Can't wait to leave the start line side by side heads up, Sam stalled against the converter/rear brake and the Chainsaw on the 2-step @5500, then..........
 Yellow, yellow, ye-GOOOOOOO!!!
 Will be sum fun.
 Keith

That sounds a bit one sided Mr Le-Blank ::) a tried and tested Pro ET bike that has won, against a completley untried Street ET bike with an old man on it. :D :D :D :D :D :D sounds cool Keith ;D

Sam. ;)
C95 sprint bike.
CB95 hybrid race bike
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CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike

Offline Sam Green Racing

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #615 on: March 04, 2011, 06:04:18 AM »
8)Thanks to all.We'll get it right.Bill
Go Bill, I want to see some powerwheelies  ;D

watch your own videos then silly arse. ::)

Sam. ;) ;D
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike

Offline voodooracer

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #616 on: March 04, 2011, 06:56:22 AM »
 Didn't mean win/lose race Sam, just the moment together at the line. Each pass is such a short-term event (well suited to my equally short attention span) have learned to break it down into smaller, savory bites. Besides, in a 1/4 mile race, The only way I could beat you was if motor internals shrapnel happened to trip lights ahead of you.
 But on test day, once you've gotten some baseline runs in and gathered some info which will include 1/8th mile times the track will let us dial in on time trial runs so you can get a taste of simulated racing, while you still (alone) race out the back door to get 1/4 mile info.
 Just a thought.
 FranknJohn ;D  and others there may provide you with real world (for your purposes) 1/4 mile dial in "racing".

Offline Sam Green Racing

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #617 on: March 04, 2011, 08:04:19 AM »
Didn't mean win/lose race Sam, just the moment together at the line. Each pass is such a short-term event (well suited to my equally short attention span) have learned to break it down into smaller, savory bites. Besides, in a 1/4 mile race, The only way I could beat you was if motor internals shrapnel happened to trip lights ahead of you.
 But on test day, once you've gotten some baseline runs in and gathered some info which will include 1/8th mile times the track will let us dial in on time trial runs so you can get a taste of simulated racing, while you still (alone) race out the back door to get 1/4 mile info.
 Just a thought.
 FranknJohn ;D  and others there may provide you with real world (for your purposes) 1/4 mile dial in "racing".

I was only jesting about the performance difference and was in fact meaning that yours might be the faster. ;D ;D ;D
Anyway with all the Busas about, it would make a nice change to see two Hondas on track together. 8) 8) 8)
Same team as well ;D I'll bring you a couple of team stickers for your bike. ;)

Sam. ;)
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike

Offline dragracer

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #618 on: March 04, 2011, 09:05:21 AM »
Didn't mean win/lose race Sam, just the moment together at the line. Each pass is such a short-term event (well suited to my equally short attention span) have learned to break it down into smaller, savory bites. Besides, in a 1/4 mile race, The only way I could beat you was if motor internals shrapnel happened to trip lights ahead of you.
 But on test day, once you've gotten some baseline runs in and gathered some info which will include 1/8th mile times the track will let us dial in on time trial runs so you can get a taste of simulated racing, while you still (alone) race out the back door to get 1/4 mile info.
 Just a thought.
 FranknJohn ;D  and others there may provide you with real world (for your purposes) 1/4 mile dial in "racing".


Damn, now you fellas are forcing me to dust off the old F model so i come out and play. It needs a set of clutches but i think she might havea few passes left in her still.

Offline Sam Green Racing

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #619 on: March 04, 2011, 09:10:35 AM »
You know it makes sence 8) 8) 8) 8)

Sam. ;)
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
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JMR Racing CB750A street ET drag bike

Offline voodooracer

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #620 on: March 04, 2011, 10:34:40 AM »
 Now this is the kind of team I can relate to. I'm gettin a free shirt, stickers for my bike and have contributed as close to nothing as can be imagined. :).
 Sam, do not hesitate to let me know if there is no-thing and I do mean ANY no-thing I can do for you and the rest of the team.
 Since you're running a slushbox, bring some clutch plates for John's old fashioned gearjammer.

Offline Sam Green Racing

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #621 on: March 04, 2011, 12:40:38 PM »
Drag racing two up round corners.



it worked, I can now post pictures.  :D :D :D :D

Sam. ;) :D
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike

Offline Sam Green Racing

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #622 on: March 04, 2011, 12:43:15 PM »


it really does work. ::)
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike

Offline Sam Green Racing

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #623 on: March 04, 2011, 01:04:31 PM »
Straight again.




Sam. ;)
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike

Offline Sam Green Racing

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Re: CB750A Street ET bracket drag bike. A year to build it.
« Reply #624 on: March 04, 2011, 01:20:48 PM »
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike