Kei Hin Carbs

[cyclebuster]

Worst peices of junk known to man. All summer fighting with this garbage. between my 81, and my 82, and my sons 83 i bet i have pulled the carbs 50 times this year. One thing after another with this hopless garbage. I cannot wait till i can get 3 sets of single carb manifolds made so i can smash this trash and haul it in for aluminum.
If it cost 5000 dollars to convert this bike to a single carb i would still do it.
the carbs are off my 81 right now, replacing the float valves AGAIN. And my 82 is now a 3 cylinder, as number 1 float valve is stuck shut and will not open for any reason.
what fool designed this rubbish?
you cannot make me belive i am alone, i am buying sweet bikes for pennies because Jesus himself cant make this crap work.
Local Honda dealer has a flat rate of $800 to make them work, and that does not include anything but a kit.
do you think i could make any money if i took them to a carnival and charged a buck a swing?

[Sagebrush]

Moved to the General Forum since this forum is for instructions or How-To tutorials.

[Whiskerfish]

I would suggest you re-examine your process. Literally hundreds of us have overhauled them with great success but it takes time and patience. Yes sometimes it does take more than one pass to get them working 100%. Do not try to accomplish it in a couple of hours or you will fail. Be meticulous and very anal. After the parts are all removed and scrubbed the first time I inspect each part individually and then scrub some more. I spend more time on the the Carb bodies than anything else making sure the passages are all flushed out and free flowing and the inside are spotless. Once everything is spotless and dried reassembly takes place on a clean white surface with every part laid out for a single body so nothing gets missed. At that point all the jets are verified for size, placement, and cleanliness before going back in. This is also the point that I decide if the rack is getting new float valves or not. They are expensive so I do not install them on every rebuild. I have found that unless some hack has been at them that most float settings do not need adjustment but everyone is checked meticulously.

I use a fair amount of brake cleaner or carb cleaner spray and a lot of soap and water and even more 120psi air.

My first rack of 1000 carbs took me over 12 hours. I have done more than a few since then and now I plan about 8 hours start to finish depending on their condition. You can not rush this.

There is no doubt that a single carb setup is simpler to maintain once setup. BUT hundreds of designs have been tried and the system has not been built yet that can compete with a properly setup stock system.

[robin1731]

I will second what Whiskerfish said. There have been way too many of them that work fine just on this board to call them junk. And the same brand of carbs were used on many other bikes and brands of bikes too.

[Missourimike]

In the process right now of going through a set of carbs for a '75. PO was a one-armed drunk who "put a kit" in them. It shows.
Broken posts, bent floats, bent pivot rods, missing parts galore. Even found one float superglued to the broken post! The whole set is now junk. I've seen almost as bad coming from "motorcycle shops". Folks think they know what they are doing or are just shooting in the dark. Rebuilding these carbs take meticulus care and intricate knowledge. It's a poor craftsman that blames the tool, and if it worked perfectly when it left the factory, what is the problem now?
I've got one bike with a Weber two-barrel on it, just for something different. It works great, idles slow and gives it a neat little sound that I don't get with a stock 4-carb set. I've had folks tell me that two-barrel carbs don't idle right, or not slow enough. I tell them, it's not the carb that is the problem, but the mechanic may need some adjustment in his thinking.

[cyclebuster]

oh i have spent untold hours on the 81 carbs, as the stupid pressed in jets were plugged. I put in the whole kit, and it all is clean, and all passages are clear. nothing but issues. so i am about to install them AGAIN. i sure hope i can get these stupid float valves to work right. adjustment isnt off, they just dont work worth a darn. I took the float drain off #1 carb on the 82, it was dry. i sprayed carb cleaner up into it while i tapped on the body softly. finally it opened, and it runs good again, back to 4 cylinders, until it does some other stupid thing. just a matter of time.
I have a 76 to rebuild carbs on, and an idiot has been in them, so anything could be wrong.
my spare 82 carbs are clean and i was going to install them on the 81, but i am giving the rebuilt set one more try before the hammer comes down.
these are not reliable carbs. there are dead wings all over needing just carb work. Everything works pretty good new.

[Dangeruss]

Wow, a dark cloud is hanging over your carbs for sure. I have almost 3 years and 20,000 trouble free miles on my KeiHin CV carbs.

[Oldewing]

My brother RAT's 1100 is over 100K miles and the carbs have never been off


If you are having that much trouble, Pistol Pete dose great work, bolt them on out of the box and go.

[starket]

Are you using aftermarket float valves? They can be a real PITA. Get some Honda ones and see how they work.

[murrayf]

i have both stock carbs and i run 2 of my wings on 32/36 dgv webers on water heated manifolds i made

i get 45 mpg at 65-70 with my weber bikes and 40-42 with the stock one

the stock ones do have a bit more power and are smoother in throttle response and the webers are louder but..

15 bucks at a flea market bought me 2 webers the rebuild kit for them is 14 dollars

one idle screw and one mixture screw PRICELESS !!!

i get on turn the fuel one twist the throttle 3 times and they fire right up i never need the choke

till its under 50 degrees so all in all i am very happy and they are totally trouble free

[phillip0123]

Murray, are you running 2 webers 1 bike or 2 bikes single weber, Randakk's manifold, cycle innovation, some other maker or homemade? A bunch of questions I know but interesting.

[murrayf]

sorry i have 2 bikes with the weber carbs one each bike i tried a dual set up once and did not like it more trouble that the stock ones and hard to keep dry
i made the manifolds for mine out of stainless food grade pie scraps and a tig welder after looking and trying some prefabbed ones

i have been playing around with the manifolds for a while and have them working well with no freezeup but wish

i had access to a flowbench maybe this winter my next project with it is making a air box with filter so they shut the h__ up

i should have them done in the next week or so

i am very pleased they are cost effective and very quicl way of getting a wing running i use one i have to test run my

bikes that i am working on even if they are getting stock carbs after run in fast to install and adjust

i now know with the jet setup i run if i rebuild one i just set the mixture screw at 1.5 turns throw it on and adjust

the idle speed so simple

[Tbell]

Hmmm! Next time I smash my thumb with a hammer I guess I'll just trash the hammer.

[CYBORG]

Hmmm! Next time I smash my thumb with a hammer I guess I'll just trash the hammer.

or blame thr nail

[Brant]

I just did a re-build on a 78 carb rack. i found a busted vacumn pistion, 2 missing pucks, a plugged jet, and an upside down air cut-off diaphram. Installed a randakk kit and did the valves, adjusted points, syned the carbs. It runs like a scalded ape.