Author Topic: Weber carb set-up  (Read 151688 times)

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Offline Tintop

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Re: Weber carb set-up
« Reply #950 on: April 19, 2019, 12:31:01 PM »
They are the original Italian Jobs..

+1 40DCOE's.  As mentioned previously, if they are even close to correct jetting and the accel pumps are working all it should take is 2 / 3 twists of the throttle to prime it for start.  The only time I ever had to use a choke with webers was when it was -3 in the winter.
1977 CB550/4 Cafe - Speed Warrior / BOTM 03/11
1980 CB750F (project)
Whittaker GBF Vintage Racing Sidecar (XS750 power) - ITG / 151's / CMR Racing Products (SOLD)
1976 CB400 SS - stock / BOTM 04/11 (SOLD)
1973 CB750 K - basket case (SOLD)
77 CB550 Cafe build
550/750 Filter Thread
Sidecar Rebuild Thread

Offline 754

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Re: Weber carb set-up
« Reply #951 on: April 19, 2019, 01:09:37 PM »
Oh yes Welcome to the club. 
 Crank wrist twice  is like the secret handshake. 
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Tintop

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Re: Weber carb set-up
« Reply #952 on: April 19, 2019, 05:09:37 PM »
Oh yes Welcome to the club. 
 Crank wrist twice  is like the secret handshake. 

 ;D ;D ;D ;D  Worked for bikes, cars, sidecar, never tried it on a boat. :)
1977 CB550/4 Cafe - Speed Warrior / BOTM 03/11
1980 CB750F (project)
Whittaker GBF Vintage Racing Sidecar (XS750 power) - ITG / 151's / CMR Racing Products (SOLD)
1976 CB400 SS - stock / BOTM 04/11 (SOLD)
1973 CB750 K - basket case (SOLD)
77 CB550 Cafe build
550/750 Filter Thread
Sidecar Rebuild Thread

Offline Don R

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Re: Weber carb set-up
« Reply #953 on: April 21, 2019, 09:23:18 PM »
 I hear the new ones are from Spain and should be cleaned before use due to grit left from machining.
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.

Offline Tintop

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Re: Weber carb set-up
« Reply #954 on: April 22, 2019, 05:20:17 AM »
I hear the new ones are from Spain and should be cleaned before use due to grit left from machining.

They have been making the carbs in Spain since the mid 90's, 1st time I've heard that.
1977 CB550/4 Cafe - Speed Warrior / BOTM 03/11
1980 CB750F (project)
Whittaker GBF Vintage Racing Sidecar (XS750 power) - ITG / 151's / CMR Racing Products (SOLD)
1976 CB400 SS - stock / BOTM 04/11 (SOLD)
1973 CB750 K - basket case (SOLD)
77 CB550 Cafe build
550/750 Filter Thread
Sidecar Rebuild Thread

Offline Don R

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Re: Weber carb set-up
« Reply #955 on: May 12, 2019, 06:28:30 PM »
 Just some online BS, possibly one guy's opinion. Maybe worth a check just in case. Same as with the Demon carbs when they moved production to Mexico. 
« Last Edit: May 13, 2019, 10:14:48 AM by Don R »
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.

Offline Tintop

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Re: Weber carb set-up
« Reply #956 on: May 14, 2019, 11:03:59 AM »
I hear the new ones are from Spain and should be cleaned before use due to grit left from machining.
They have been making the carbs in Spain since the mid 90's, 1st time I've heard that.
Just some online BS, possibly one guy's opinion. Maybe worth a check just in case. Same as with the Demon carbs when they moved production to Mexico. 

All that said I always flush them out with carb cleaner before assembly, some of these NOS carbs have been sitting on shelves for a long time.  The NOS Italian made one I used on the sidecar was made in the 70's, so was pushing 50 when 1st un-boxed & used. :)
1977 CB550/4 Cafe - Speed Warrior / BOTM 03/11
1980 CB750F (project)
Whittaker GBF Vintage Racing Sidecar (XS750 power) - ITG / 151's / CMR Racing Products (SOLD)
1976 CB400 SS - stock / BOTM 04/11 (SOLD)
1973 CB750 K - basket case (SOLD)
77 CB550 Cafe build
550/750 Filter Thread
Sidecar Rebuild Thread

Offline 754

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Re: Weber carb set-up
« Reply #957 on: May 15, 2019, 07:05:28 PM »
Anyone ever run Dellortos on a 4 cyl ?
 I have at least 2 pairs.. time to start using up my stock.
 Of course manifolds need to be made.
 I could use baseline jetting for Dell,s... if anyone has it.

Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Tintop

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Re: Weber carb set-up
« Reply #958 on: May 15, 2019, 07:21:29 PM »
Anyone ever run Dellortos on a 4 cyl ?
 I have at least 2 pairs.. time to start using up my stock.
 Of course manifolds need to be made.
 I could use baseline jetting for Dell,s... if anyone has it.

I had a set on a Toyota TC 2TG 1600 (bored/stroked to 2L).  Tuning was very similar for the Weber 40 DCOE's later used on the same engine.
1977 CB550/4 Cafe - Speed Warrior / BOTM 03/11
1980 CB750F (project)
Whittaker GBF Vintage Racing Sidecar (XS750 power) - ITG / 151's / CMR Racing Products (SOLD)
1976 CB400 SS - stock / BOTM 04/11 (SOLD)
1973 CB750 K - basket case (SOLD)
77 CB550 Cafe build
550/750 Filter Thread
Sidecar Rebuild Thread

Offline sohc boy

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Re: Weber carb set-up
« Reply #959 on: May 17, 2019, 03:55:46 AM »
Anyone ever run Dellortos on a 4 cyl ?
 I have at least 2 pairs.. time to start using up my stock.
 Of course manifolds need to be made.
 I could use baseline jetting for Dell,s... if anyone has it.
Have two sets of Dellorto's , 40mm DHLA ,and manifolds, sold as kit from Lynx ,never ran em, will look see what jets an vent's
i live by the voice inside my head

Offline Tintop

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Re: Weber carb set-up
« Reply #960 on: May 17, 2019, 05:12:47 AM »
Anyone ever run Dellortos on a 4 cyl ?
 I have at least 2 pairs.. time to start using up my stock.
Of course manifolds need to be made.
 I could use baseline jetting for Dell,s... if anyone has it.

I'm not sure at this point,(been a very long time ;)), but seems to me that Webers, Dellortos, and Solex (?) all work on the same manifolds.
1977 CB550/4 Cafe - Speed Warrior / BOTM 03/11
1980 CB750F (project)
Whittaker GBF Vintage Racing Sidecar (XS750 power) - ITG / 151's / CMR Racing Products (SOLD)
1976 CB400 SS - stock / BOTM 04/11 (SOLD)
1973 CB750 K - basket case (SOLD)
77 CB550 Cafe build
550/750 Filter Thread
Sidecar Rebuild Thread

Offline 754

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Re: Weber carb set-up
« Reply #961 on: May 17, 2019, 06:00:33 PM »
Webers and Dellortos for sure the same,  more carbs than manifolds out there.
 I stil, have 3 different ones.
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline sohc boy

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Re: Weber carb set-up
« Reply #962 on: May 18, 2019, 02:43:02 PM »
dont know what size engine these were on ,main 125 ,air 200, emulsion 7772.5
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Offline 754

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Re: Weber carb set-up
« Reply #963 on: May 18, 2019, 07:49:22 PM »
 Thanks I wil, try to dig them out and see what they have, plus I have some extra jets.
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Don R

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Re: Weber carb set-up
« Reply #964 on: September 07, 2019, 07:32:23 PM »
 I'm hoping to mount mine soon, someone on FB was asking for help and I posted a link to this.
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.

Offline corky

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Re: Weber carb set-up
« Reply #965 on: September 16, 2019, 08:08:10 AM »
hey guys,

This is an awesome thread....there is an amazing amount of information in here.

Does anyone have some jetting info on running webers on a larger motor, more in the 1000cc area?  I see a lot of good info for 750-836 motors!

Thanks,
Daniel

Offline Tintop

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Re: Weber carb set-up
« Reply #966 on: September 16, 2019, 08:59:55 AM »
hey guys,
This is an awesome thread....there is an amazing amount of information in here.
Does anyone have some jetting info on running webers on a larger motor, more in the 1000cc area?  I see a lot of good info for 750-836 motors!
Thanks,
Daniel

Your idle jets should be very similar, if not the same.  Surprising how little these change vs engine size.  As for mains / airs / emulsion tubes, I'd start out with what has been posted here before for the larger engines, maybe go 1 step richer on the mains.  Also be aware if you dyno tune that cracking the throttle will engage the accel pump and throw the readings off, slow roll-on works better.
1977 CB550/4 Cafe - Speed Warrior / BOTM 03/11
1980 CB750F (project)
Whittaker GBF Vintage Racing Sidecar (XS750 power) - ITG / 151's / CMR Racing Products (SOLD)
1976 CB400 SS - stock / BOTM 04/11 (SOLD)
1973 CB750 K - basket case (SOLD)
77 CB550 Cafe build
550/750 Filter Thread
Sidecar Rebuild Thread

Offline scottly

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Re: Weber carb set-up
« Reply #967 on: September 17, 2019, 07:40:43 PM »
Daniel, a basic rule-of-thumb is 28mm chokes for 736cc, 30mm chokes for 836cc, and 32mm chokes for 1000cc. A 1000cc bike will run just fine with 28mm chokes, but may not make as much HP on the dyno as it would with 32mm chokes. The main jet size is related to the choke size, the engine displacement, the emulsion tubes, auxiliary chokes etc, but in the end, Webers are somewhat forgiving. What parts do you have on hand? ;) 
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Offline 754

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Re: Weber carb set-up
« Reply #968 on: October 04, 2020, 10:22:10 AM »
Just a reminder of how hot these can look...
« Last Edit: October 04, 2020, 10:24:50 AM by 754 »
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Tom

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Re: Weber carb set-up
« Reply #969 on: March 23, 2021, 02:49:30 AM »
These are still available new in Melbourne Oz a bit expensive but available.

https://www.lynxauto.com.au/honda-motorcycle-cb-750-2-x-weber-dcoe-manifold.html
'59 T120.,'70 T120R Had one new.,'69 CB750 Oz Sandy Ruby Red.,'69 CB750 Oz Sandy Blue Green.,'70 CB750 K0 Candy Gold.,'71 CB750 K1 Valley Green I bought new.,'71 CB750 K1 Candy Garnet Brown.,'76 Rickman Honda CR750 R.C. Eng Cobra Powered. Two CB750 Choppers a Amen Saviour and a a Santee rigid arm Softail. A ‘72 Z1 Jaffa, and lotsa fun Honda Monkey bikes.

Offline Medyo Bastos

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Re: Weber carb set-up
« Reply #970 on: March 23, 2021, 06:00:41 PM »
I’ve got an MPD under my bed. 250 bones shipped in the mainland


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Offline Don R

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Re: Weber carb set-up
« Reply #971 on: September 22, 2021, 01:12:13 PM »
 Without re-reading the entire thread is there any specific throttle cable that works with Webers and a center pull linkage? I think it's going to be just a short pull cable and cut to fit. Right? 400F bars and a k2 right control. 
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.

Offline Tintop

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Re: Weber carb set-up
« Reply #972 on: September 22, 2021, 03:47:51 PM »
I had Motion Pro make 1 for the sidecar's single cable twist to Weber set-up.
1977 CB550/4 Cafe - Speed Warrior / BOTM 03/11
1980 CB750F (project)
Whittaker GBF Vintage Racing Sidecar (XS750 power) - ITG / 151's / CMR Racing Products (SOLD)
1976 CB400 SS - stock / BOTM 04/11 (SOLD)
1973 CB750 K - basket case (SOLD)
77 CB550 Cafe build
550/750 Filter Thread
Sidecar Rebuild Thread

Offline 754

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Re: Weber carb set-up
« Reply #973 on: September 22, 2021, 04:04:39 PM »
You can cut down a stock cable..
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Don R

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Re: Weber carb set-up
« Reply #974 on: September 22, 2021, 06:54:59 PM »
 That's what I was hoping Frank. That K2 had some seriously tall bars on it so that cable has no use to me at all unless I cut it.
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.