Author Topic: Big CC sohc drag race carbs Q's?  (Read 6818 times)

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Offline dragracer

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Re: Big CC sohc drag race carbs Q's?
« Reply #25 on: June 23, 2017, 05:49:56 pm »
If he ran 160mph, he'd be deep into the 4 second zone in the 1/8th mile. Mid to low 4's.

Offline MRieck

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Re: Big CC sohc drag race carbs Q's?
« Reply #26 on: June 23, 2017, 06:31:06 pm »
That's quick and fast
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Offline Don R

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Re: Big CC sohc drag race carbs Q's?
« Reply #27 on: June 23, 2017, 08:30:07 pm »
 Just for some carb and ET/speed comparisons,
We're doing some Super Comp racing at Cordova this weekend. I use a Quick Fuel 1150 cfm Dominator on a 567" big block with VP Q16 fuel. I have about 7 gallons left, and 4 in the tank, if we win both days we'll be on fumes by Sunday. Nasty, $13 a gallon fumes. We run wide open for .1 second then throttle stop to 4250 rpm for about 2 to 2.3 seconds to slow down to run 8.90 in the 1/4 mile at around 175.
  It's a far cry from that lectron fed briggs that ran 9.60's in the 1/8 mile. That junior was at an 1/8 mile track in the lanes for first round one time and had the same dial in as a 455 GTO. The Pontiac guy almost cried.

 Frank,  Last Sunday we had a losing ,011 red light as did our opponent. The winner got a print out and said it went to the 5th digit to find the winner. Mr Chronodeck will always choose a winner
« Last Edit: June 23, 2017, 08:34:08 pm by Don R »
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Offline dragracer

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Re: Big CC sohc drag race carbs Q's?
« Reply #28 on: June 23, 2017, 10:09:46 pm »
You gotta love those 5th digit win tickets.

Offline Bill/BentON Racing

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Re: Big CC sohc drag race carbs Q's?
« Reply #29 on: June 24, 2017, 07:42:30 pm »
RS your best bet. However, you want the 33's,  great carbs also, I'll do $450.00 shipped! Let me know,  thanks,  Bill
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Offline scottly

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Re: Big CC sohc drag race carbs Q's?
« Reply #30 on: June 24, 2017, 07:57:27 pm »
Strike while the iron's hot, Don; Billy has to pay for his new toy. ;D
Don't fix it if it ain't broke!
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Offline sohc boy

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Re: Big CC sohc drag race carbs Q's?
« Reply #31 on: June 30, 2017, 05:27:39 am »
from the 80's Dale Walker's 1170 with 29 smoothbores
i live by the voice inside my head

Offline Bill/BentON Racing

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Re: Big CC sohc drag race carbs Q's?
« Reply #32 on: July 01, 2017, 06:07:10 am »
Here you go, no they ain't 836cc Dale! Lol. Wonder what Walker ride they were in?
BentON Racing Website
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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.
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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.
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Offline Medyo Bastos

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Re: Big CC sohc drag race carbs Q's?
« Reply #33 on: July 01, 2017, 06:14:42 am »
Nice 65mm slugs


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Offline Bill/BentON Racing

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Re: Big CC sohc drag race carbs Q's?
« Reply #34 on: July 01, 2017, 09:23:21 am »
Yeh, all of 73mm,LMAO
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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.
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Offline kmb69

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Re: Big CC sohc drag race carbs Q's?
« Reply #35 on: July 01, 2017, 11:01:07 am »
Here you go, no they ain't 836cc Dale! Lol. Wonder what Walker ride they were in?
Yeh, all of 73mm,LMAO

He obviously was not concerned with sealing the "quad-studs"  ;)

Offline dragracer

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Re: Big CC sohc drag race carbs Q's?
« Reply #36 on: July 01, 2017, 09:32:27 pm »
from the 80's Dale Walker's 1170 with 29 smoothbores

Now that's a great goal for someone on the forum to shoot for using today's technology. Interesting that he used 29's. But then Dale was a master in figuring out how to make small things go big numbers.

Offline sohc boy

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Re: Big CC sohc drag race carbs Q's?
« Reply #37 on: July 02, 2017, 02:01:35 am »
it is good goal to aim for Franky , ive had it stuck to my shed wall for long time ,......early barrel i was going to go with before i bought  RC Eng big block, 72 mm bore, honda 1100F sleeves
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Offline 754

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Re: Big CC sohc drag race carbs Q's?
« Reply #38 on: July 02, 2017, 07:36:22 pm »
Maybe its time to flowtest some carbs...
 Can carbs that outflow the port add power ?
 I bet the 29,s never bogged..
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Offline scottly

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Re: Big CC sohc drag race carbs Q's?
« Reply #39 on: July 02, 2017, 08:02:49 pm »
Not in my experience, Frank. No real gains with 32mm vs 30mm chokes with a stock K1 head. ;)
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Offline Don R

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Re: Big CC sohc drag race carbs Q's?
« Reply #40 on: July 03, 2017, 02:23:46 pm »
 I'm loading up for the Super Chevy event swap meet Saturday. Hopefully I can raise some Carb cash L0L! 
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
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Offline Don R

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Re: Big CC sohc drag race carbs Q's?
« Reply #41 on: September 06, 2017, 09:43:52 pm »
 I sold a couple bikes and I'm looking at options for the rs34's on ebay, $120 used but they seem to have a center fuel fitting that might be an issue for reracking,  $647 new with tees between 1-2 and 3-4 or $725 from cycle x racked and set up for a cb. Are there other options or opinions?
No matter how many times you paint over a shadow, it's still there.
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 You don't need a weatherman to know which way the wind blows.

Offline dragracer

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Re: Big CC sohc drag race carbs Q's?
« Reply #42 on: September 06, 2017, 10:57:46 pm »
I sold a couple bikes and I'm looking at options for the rs34's on ebay, $120 used but they seem to have a center fuel fitting that might be an issue for reracking,  $647 new with tees between 1-2 and 3-4 or $725 from cycle x racked and set up for a cb. Are there other options or opinions?

Personally I would go with the new ones from Cycle Ex. They work great for Bill. I'm running a set of 36mm RS's on my 1030. I bought them new but they fit an early Ninja 900/FJ1110. The spacing is close. I didn't rerake. I offset ground my rubber intake boots to compensate for the slightly off spacing. I've got an F3 head so the inlets are larger than the K but still required a little opening up to fit the carbs- that's where I incorporated the offset.

On my new project bike, i'm going to run a set of 34mm Lectrons. The one issue I've encountered on the mock up is the #3 carb fuel inlet nipple and the idle adjuster screw bumps against the #2 carb nipple and screw. There just isn't enough room to avoid this problem. In looking at the body of the Lectron, there are provisions to install the fuel nipple on the opposite and as well as relocating the idle screw. I contacted Lectron and they can handle that task. I've got to get the carbs freshened up anyway so the mods will be done at that time.

Offline MRieck

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Re: Big CC sohc drag race carbs Q's?
« Reply #43 on: September 07, 2017, 05:30:23 am »
It isn't hard to rerack the 34's....I have done it on my set and for several other people.. The center fuel feed pipe has to be shortened. There are a couple of other tips but it isn't difficult. I believe they are the best bang for the buck
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Offline Don R

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Re: Big CC sohc drag race carbs Q's?
« Reply #44 on: September 07, 2017, 07:33:06 am »
 Thanks for answering silly questions, I have a nice mikuni jet kit my brother used during his days as a kawi mechanic back when the 900's and Z1's were new We still have an EGT meter from the jr dragster days and am not above robbing the racepack data recorder off my daughters S/C dragster for testing.  That said, a dyno day would be awesome and I'm friends with a drag bike shop owner.
 Whether this will ever see the track is another question, my Dragster driving Daughter is having a cow about me racing a bike. L0L!
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
 You don't need a weatherman to know which way the wind blows.