76 CB360, Cherry Bomb at Barber's

Re: New Dual O2 sensors, 76 CB360, the Pig

Should run test print today on your float height. Going to print up 3 separate versions for now and see if i cant engineer an adjustable version at some point.
 

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Re: New Dual O2 sensors, 76 CB360, the Pig

adventurco said:
Should run test print today on your float height. Going to print up 3 separate versions for now and see if i cant engineer an adjustable version at some point.

Dude!!! you are so the man!
 
Re: New Dual O2 sensors, 76 CB360, the Pig

that is very cool, but float height is not a tuning tool it doesnt effect tune unless way out of whack
just set them close and fergetaboutit
 
Re: New Dual O2 sensors, 76 CB360, the Pig

xb33bsa said:
that is very cool, but float height is not a tuning tool it doesnt effect tune unless way out of whack
just set them close and fergetaboutit

100 THUMBS UP EBERT
 
Re: New Dual O2 sensors, 76 CB360, the Pig

xb33bsa said:
that is very cool, but float height is not a tuning tool it doesnt effect tune unless way out of whack
just set them close and fergetaboutit

Yes it is. My answer there is as broad as yours and needs clarification. That's one problem with this format - it's not a very efficient way to transfer complete information, so we do it in generalities.

On CV carbs it is sometimes the only tool to get parts of the range correct. But in most situations it is a fine tuning effect.

Higher fuel levels have a slightly higher head of pressure and run richer than lower fuel levels. How much - that's the question. For example if say the bottom end and top end are slightly rich and mid throttle is too rich, drop the fuel level slightly may bring that back into line along with jetting changes for pilot and main jets.

It's subtle but can be the only tool left in the tool bag.
 
Re: New Dual O2 sensors, 76 CB360, the Pig

Hey guys...Excited as I am about the experimental needle work. Im just gonna enjoy riding her atleast for the next couple months. Shes really running pretty darned good.

And simply due to being a 360...thats saying a whole lot. ;) Im pretty skeptical about how long she can keep this up.
 
Re: New Dual O2 sensors, 76 CB360, the Pig

xb33bsa said:
that is very cool, but float height is not a tuning tool it doesnt effect tune unless way out of whack

Nope, it is a tuning tool
The float height will adjust the level of fuel in float bowl and consequently affect if motor is running rich or lean
Add some heat and vibration then even 1mm variation can have a major effect
The reason carb specs have a 'range' isn't to allow piss poor setting but to compensate for different running conditions, altitude variations, etc
 
Re: New Dual O2 sensors, 76 CB360, the Pig

crazypj said:
Nope, it is a tuning tool
The float height will adjust the level of fuel in float bowl and consequently affect if motor is running rich or lean
Add some heat and vibration then even 1mm variation can have a major effect
The reason carb specs have a 'range' isn't to allow piss poor setting but to compensate for different running conditions, altitude variations, etc

Because, otherwise floats would be more of a "fixed" part. Meaning, "non-adjustable" Like comparing a "fixed" size internal jet to the "adjustable" A/F mix needle. If the A/F didnt need to be tuned for the particular environment at hand...it would be permanently fixed jet.
So even though the intent of the manufacturer may not have been to use float level as a "performance enhancement tuning tool". Its intent is more of a "maintenance tuning thing, (set it and occasionally check it)". But, can be employed as such. Why not use it, as such?
 
Re: 76 CB360, the Pig

Started using a new parametric CAD program...This was a good test for the printer tolerances/modeling program scale. They all came off the print bed within 0.1-0.2mm accuracy. With a ruler the heights are dead on. Get em in the mail tomorrow. 8)
 

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Re: 76 CB360, the Pig

Adventurco and his 3d printer rock!

From this...last week.

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To this...arrived yesterday. 8)

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Re: 76 CB360, the Pig

adventurco said:
Started using a new parametric CAD program...This was a good test for the printer tolerances/modeling program scale. They all came off the print bed within 0.1-0.2mm accuracy. With a ruler the heights are dead on. Get em in the mail tomorrow. 8)

Nice!
 
Re: 76 CB360, the Pig, Building stock 745B's top to bottom

Photobucket has really botched this thread up for me. But, whatever.

Starting to build a fresh pair of stock 745B's for Barber Vintage fest in B-ham. Why, Because I have a sickness.
This thread should be helpful for any noobs just looking for info on carb prep.
This info is good for 754A carbs also. The only diff being non-removable air correctors.

It starts w an NOS pair of filters I bought off ebay years ago when I first got my bike. I think I paid $25 for the pair. Times have changed.

If youre wanting to run pods, you will need to contact crazyPJ.

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For a proper cleaning they need disassembled. If you find jets and parts are hard to remove soak em down w penetrant and use heat gun to warm bodies. Tight jets usually come free pretty easily. I will try to reuse as much stock brass as possible.

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Before cleaning w chemicals. I am just checking parts for fitment.
I use a big flat file to LIGHTLY run over tops and bowls to ensure they are flat (looking for any warping that could affect O-ring sealing)

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PO tried sealing bowls w blue RTV. It wont work. Blue RTV is not fuel resistant and will make a mess out of things.
Clean that shit out carefully. Dont scratch the O-ring surface. Heat gun helps w hardened bowl gaskets.

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Blue silicone turns into crusty powdery shit CLOG and its hard to clean. I will get as much as possible w dremel.

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Make sure to clean/polish float seat o-ring sealing surface as good as possible and double check it for burrs.

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Before dipping the bodies I fill a bottle w chem and squirt it into all the ports as best I can to avoid trapped air bubbles (not getting cleaner)

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Especially the pilot/idle circuits.

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Once dropped into dip can, I will flip em around and shake them a few times to work out any trapped air.

I learned to use a felt dremel bit and dab of toothpaste to polish float needle seat surface.

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Re: 76 CB360, the Pig, Building stock 745B's top to bottom

After removing from dip, rinse well w water. Make absolutely certain water sprays from ALL 3 pilot holes and the larger single idle feed, by spraying hose into the Air/Fuel adj needle hole. These two circuits are combined internally and can be difficult to clear debris trapped inside.
Watch for good flow through air corrector holes (under diaphragm in carb tops) the feed to the jetting holes.
And from fuel inlet through the float seat hole.

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Re: 76 CB360, the Pig, Building stock 745B's top to bottom

Inspect the overflow tubes in bowls for hairline cracks. this was on my wifes 78 CB400a

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Re: 76 CB360, the Pig

Back at it I see. Neat little trick for the needle and seat, I need to try that on the XL...right now if i dont have a screwdriver handy i get fuel all over the floor of the shop.

What's the reason for the new set of carbs?
 
Re: 76 CB360, the Pig

advCo said:
What's the reason for the new set of carbs?

good question, I have asked that myself. W the current set up, modified carbs and K&Ns, She runs super, plenty of power and getting 60-70mpg.

I have swapped in the stock boxes w these modified carbs. And there seems to be a small loss of power above 5k rpm.
Able to build rpm faster w the K&Ns.

Simple curiosity really (coupled w the fact I cant keep my hands off it.)

As w a lot of the "cool kids" back in the day. After getting it running (not well, but running none the less) I immediately threw pods at her.
So, I really have no idea how well a 360 can run w the stock set up.
I just want to find out. If its better, worse or same. I imagine it will be about the same.
 
Re: 76 CB360, the Pig

advCo said:
Back at it I see. Neat little trick for the needle and seat, I need to try that on the XL...right now if i dont have a screwdriver handy i get fuel all over the floor of the shop.

I had to modify the felt polishing tip small enough to fit inside the needle seat.

I chucked up the larger felt tip in dremel got it spinning up to speed, turned on the bench grinder and gently ground the felt tip down to a good fit.
 
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