acetelyne n hammertone ADVtwin

on to the nos valves/head i scored it at a yardsale way back when, when i scored a bunch of CYB 350 nos engine kit parts
somebody had been in there tyding up the bowls and the seats are so good its hard to believe they came like this ,but i have no story on this head
the valves are so tits with the black nitrided finish 8)
i have some very fine lapping comp which i gently scrubbed in valves with to verify seal and partner them up
intake ports the manifolds i offset up so all major material removal was the top of intake ports
the intake port floors were simply scruffed down to smooth flow care taken to remove minimal stock from floors
 

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exhaust ports
only went in there to clean up and hopefully achieve what the original design intended
just cleaning up the nasty of them makes a noticable visual volume change i wouldn't want to enlargen them more
 

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datadavid said:
Those are hella tiny intake ports?
ha 'hella tiny' i dint know you were a mexican,i love the mexicans
naw not really,same valves and port bowl area as cb/cl350 except where the carb bolts on the sl uses hella small 24mmm crabs so its is smaller down in a couple inches
i am using the 750 ko keihins at 29mm my inlet port is matched to my rubber manifolds and at a bit over 28m
good intake charge velocity for good troddle response eh
 
What's going on with that chattered edge around the lip of the spark plug hole?
 
irk miller said:
What's going on with that chattered edge around the lip of the spark plug hole?
thats pre history looks like they hit it gently with a chattermore it should help bloom the flamefront
sh ! quiet its talkin to me
ah !get down from there !! you aint shoppin' this aint a hardware store keep yer mits in yer pockets !
 
i had t go back in
 

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I had managed to forget how small and crappy stock ports are and how much of lump they have near the guide. What's worse though is the crappy valve seat geometry and the thick valve stems right where the flow should be.

The best reason to fit oversize valves on those things is to improve geometry just before the valves.

@8mm Keihin carbs from a CB750 K0 are my favorite cheap carbs for a streetable Honda 350 twin if you can find them. You can use later model carbs of the same design but they are harder to convert to cable pull and to fit cable adjusters. I used later carbs for years on a CB77 racer. The nice thing is that they have the same 26mm slide diameter as CB77 carbs but are taller, so at small openings they are like a smaller carb and at full open they have more area and flow.
 
teazer said:
I had managed to forget how small and crappy stock ports are and how much of lump they have near the guide. What's worse though is the crappy valve seat geometry and the thick valve stems right where the flow should be.

The best reason to fit oversize valves on those things is to improve geometry just before the valves.

@8mm Keihin carbs from a CB750 K0 are my favorite cheap carbs for a streetable Honda 350 twin if you can find them. You can use later model carbs of the same design but they are harder to convert to cable pull and to fit cable adjusters. I used later carbs for years on a CB77 racer. The nice thing is that they have the same 26mm slide diameter as CB77 carbs but are taller, so at small openings they are like a smaller carb and at full open they have more area and flow.
hah you stole my plane, :D
i AM using a near nos set of L R 750 KO crabs just got done making up a throttle y cable its been the plan all along 28mm and the ovalised bore is tits for good response i figger
they are basically grown up sl 24mm carbs, identical design
 
a giant angle finder each degree well spaced the key making sure its calibrated accurate and having it and forks pointed straight forward all squared up
 

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xb33bsa said:
ha 'hella tiny' i dint know you were a mexican,i love the mexicans
naw not really,same valves and port bowl area as cb/cl350 except where the carb bolts on the sl uses hella small 24mmm crabs so its is smaller down in a couple inches
i am using the 750 ko keihins at 29mm my inlet port is matched to my rubber manifolds and at a bit over 28m
good intake charge velocity for good troddle response eh

Godfearing white swedish mexican at your service!
 
prelash on the ko crabs ko crabs are happy crabs fact is this heater here is gonna be a glamour hog ,gridle plate for the crabs gets finished latr i left it wide i can sense some glaminar flow situtsaions mite rear head
might need to confront the whole glamlipper flow situation gonna needc maybe these caddy toedoor jams but the flow calls it im gonna need all my backround in nigerian engineering fo asses glaminar floor properties tattyletali thats it no wait telltaile it will match the glamlipoper floe hmmm peacock feather fucking too sissie hmm feathers bah fuk
ahhhsoooo !!!
i have an old fur cap its gotta coon tail, i even knew the coon dog what treed it
a coon tail tell tail lashed to each plug cap yep
 

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imagines es
 

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next up final assemblage of the heater
 

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And the build goes on ::)

http://advrider.com/index.php?threads/the-african-twin-honda-never-built.1181059/
 
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