Author Topic: Weber + ARD Mag setup no start issue  (Read 3779 times)

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Offline valt

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Re: Weber + ARD Mag setup no start issue
« Reply #175 on: October 18, 2020, 04:12:14 pm »
As a quick aside I would really like to say a huge thank you to everyone who took the time to respond and help me try and figure this out. I super appreciate it, for the most part its just me trying to figure this stuff out and its definitely good to hear from people who have way more experience with non stock setups like this.

I will be honest I'm at least slightly nervous about this bike now lol. The other motor was well worn so it was certainly down on power. I'm imagining going to the larger pistons is going to make the motor pick up power in the lower rpm range and its already handful there. I have found that with the webers it is very snappy down low as well, where it certainly was not with stock carbs.

Offline 754

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Re: Weber + ARD Mag setup no start issue
« Reply #176 on: October 18, 2020, 04:33:53 pm »
Its gonna be so worth it, way more fun, maybe better gas mileage. .  Enjoy it.l
Maker of the WELDLESS 750 Frame Kit
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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 BPellerine

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Re: Weber + ARD Mag setup no start issue
« Reply #177 on: October 19, 2020, 01:01:46 pm »
glad you had success!yes it will be snappy,but mostly after 3000 rpm at least thats what I found.bill
1978 CB 750K ard and webers
another anfob

Offline scottly

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Re: Weber + ARD Mag setup no start issue
« Reply #178 on: October 19, 2020, 07:56:16 pm »
I have found that with the webers it is very snappy down low as well, where it certainly was not with stock carbs.
The first 1/8 turn of the throttle makes a big difference with Webers, and the last 1/8 has almost no effect. ;) I re-shaped the part of the throttle tube where the cable rides to slow the initial amount of throttle opening, which helped a little.
Don't fix it if it ain't broke!
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Offline valt

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Re: Weber + ARD Mag setup no start issue
« Reply #179 on: October 25, 2020, 06:40:07 pm »
Well I have had it going for a bit now. I have found that its kind of scary to start when cold, since its full advance all the time. I have had it kick back with a vengeance several times. But it seems to run really good power is smooth across the board. One thing I noticed is that I'm getting a bit of smoke from the breather at idle. I was kind of attributing that to valve guides being worn. But That vent is the crank case vent is it not? It should be noted that I have a filter on it so its not just venting to nothing.

Also the modified scooter throttle cable I was using broke. I ordered a much nicer one from mikesxs.com, but for some reason it binds and causes the throttle pull to be very heavy and not return. I did some little tweaks to it and made it be better but I'm still having to use a 1.5 lbs spring to make it return correctly. This obviously makes the throttle pull be exceedingly heavy.

Offline Don R

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Re: Weber + ARD Mag setup no start issue
« Reply #180 on: October 25, 2020, 07:10:26 pm »
 I made a deal on a 900cc sohc motor but can't seem to complete it so I'm moving on and will put my ard and webers on a different engine. You can bet I'll refer to this thread many times. My plan is get it running well and swap one item at a time.
No matter how many times you paint over a shadow, it's still there.

Offline BPellerine

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Re: Weber + ARD Mag setup no start issue
« Reply #181 on: October 26, 2020, 05:44:03 pm »
mine does not kick back valt,maybe retard it just a touch,the cable must really be binding,webers have a real light throttle,I dont know what linkage you have but I just made up a bracket so I could use a stock honda cable with the carb end ball cut off.bill
1978 CB 750K ard and webers
another anfob

Offline 754

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Re: Weber + ARD Mag setup no start issue
« Reply #182 on: October 26, 2020, 08:18:26 pm »
And figure out how much to prime.lt maybe only needs part squirt and 2 might be too much...
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 scottly

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Re: Weber + ARD Mag setup no start issue
« Reply #183 on: October 26, 2020, 09:33:28 pm »
Well I have had it going for a bit now. I have found that its kind of scary to start when cold, since its full advance all the time. I have had it kick back with a vengeance several times.
Some kicking back is normal with full advance, but you may be a bit more than the normal 35* full advance?
Don't fix it if it ain't broke!
Helmets save brains. Always wear one and ride like everyone is trying to kill you....

Offline valt

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Re: Weber + ARD Mag setup no start issue
« Reply #184 on: November 17, 2020, 02:40:53 pm »
mine does not kick back valt,maybe retard it just a touch,the cable must really be binding,webers have a real light throttle,I dont know what linkage you have but I just made up a bracket so I could use a stock honda cable with the carb end ball cut off.bill

Yeah I ended up getting a cable from mikesxs.com which works pretty well. I had to use a different throttle tube and had to message it a bit as it was binding in my throttle housing. But now its nice and light and it fires right up usually. I had to end up putting some loctite on the carb support bolts as they kept wanting to back out and that would cause the carb to flop around and for what ever reason make it VERY difficult to start. I'm still waiting on getting the head back with the stainless valves, but once I get it back I'm going to order a new cycle x cam.

Offline 754

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Re: Weber + ARD Mag setup no start issue
« Reply #185 on: November 17, 2020, 04:47:11 pm »
Remind me again why the carbs are at such a steep angle ? Can't be helping any.. they are usually level..
 How's gas mileage when not twisting on it all  the time. ..?
« Last Edit: November 17, 2020, 04:49:01 pm 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 valt

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Re: Weber + ARD Mag setup no start issue
« Reply #186 on: November 19, 2020, 08:10:43 am »
Remind me again why the carbs are at such a steep angle ? Can't be helping any.. they are usually level..
 How's gas mileage when not twisting on it all  the time. ..?

Thats how they mount when using the stock carb boots and in a lot of car setups its not uncommon for them to be at a bit of an angle. When the mounts are tight it starts and runs without issue.

Offline Tintop

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Re: Weber + ARD Mag setup no start issue
« Reply #187 on: November 19, 2020, 08:37:12 am »
Keep in mind that ALL Weber books recommend that the carbs not be more than 5* +/- from horizontal. More than this will affect the float level and cause issues.
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1976 CB400 SS - stock / BOTM 04/11 (SOLD)
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Offline 754

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Re: Weber + ARD Mag setup no start issue
« Reply #188 on: November 19, 2020, 10:57:49 am »
Yours is the only one I have seen at that angle in 45 years..
 And EVERY RC manifold I have seen,sat near level. .... make that all manifolds.
 Only exception, drag bikes with 2 or more motors , or raised ports.
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 valt

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Re: Weber + ARD Mag setup no start issue
« Reply #189 on: November 19, 2020, 11:54:51 am »
Yours is the only one I have seen at that angle in 45 years..
 And EVERY RC manifold I have seen,sat near level. .... make that all manifolds.
 Only exception, drag bikes with 2 or more motors , or raised ports.

It should be noted that my motor is in a hand made frame and is entirely likely that its laid forward a bit more then a normal frame.

Offline 754

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Re: Weber + ARD Mag setup no start issue
« Reply #190 on: November 19, 2020, 04:35:54 pm »
Your motor is pretty much level ....
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

 

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