carburetor/throttle upgrade. oh yes, i went there...

G

gone_fishin

Guest
i think i may have stumbled upon the sophisticated grandpappy of the "happy time" carby.
this is uncannily close...off a 1978 honda express. matter of fact, it's so close i'm betting it'll work. carb w/choke, throttle w/choke, brake lever, killswitch, brakelight. what a tweak this is gonna be if i can pull it off.
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like the "happy time" it has a mechanical idle-screw. it has a choke that (i think) affects only idle, an idle-mixture screw, & i'm
guessing it has mixture slots on the needle, too, because i can see the circlip. if i'm figuring this right, the express needed a LOT of rpm's to do 30mph, so i bet flow is already adequate, i'm not adverse to punching out the jet tho as last resort.
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now that the chain tensioner is working right, i need something to do in the morning, so i'll tear it down and have a look.

at the very least i'll have a neat throttle assembly 8)

any info would be groovy :)
 
Hmmm...that looks interesting. Are you going to bolt it right to the cyl. or will you need a new manifold? If you need a new manifold, I know someone who could make one for you :D
 
it's almost the exact size as the stock carb, so bolting direct to the cylinder would jam it into the clutch cable.

first i'll just rig something up until i know it works, then we'll talk to your "friend" about a manifold, i hope he works cheap ;)
 
wavygravy showed up just in time to run-get-me a piece of heaterhose & take some pics :)

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will it?
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it sure will!
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:devilish: :devilish:

i'll keep yas posted 8)
 
looks good.....what does the 2nd carb cable do? choke?? nevermind.... I see the choke lever on the grip.

performance??
 
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i have 187 miles on a roller-bearing "70"...running penzoil at 32:1...it's starting to kick in really nicely.

the happy time carb: predictable starts & reliable. sorta decent scoot up to 19-21 and it gets a bit flat...if i hold it at 90% throttle i eventually get 26-28mph on the level.

the ???shin carb: hard start, excellent scoot up to 20mph, then i have to feather it around 75% throttle but i get a strong 28mph cruise...this can only get better when i make a real intake and learn how to set it.

any advice or guidance on this carby?
 
you know, 'kronic, i never thought i'd be messing around in here at all :LOL:

ok, back to the happy-time carb for now...i'll have to work on an intake & really get the new one clean and functioning right.

the honda throttle cable & cap fit right on the happy-time carby, too easy :)
 
and i'm still goin' there!

a buddy offered to weld whatever i could come up with...waste not, want not ;)
 

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