Carby Keihin carb clone

Also if you are running hi compression u really ought to be running hi octane I buy 5 gallon drum of 118 and mix it with a little pump gas you would not believe the difference night and day
Where do you get that, whats it called, how much is it, and how do you mix yours....?
 
I was thinking of trying the premium at the shell station but idk about that, I heard ethanol is bad for these engines. Does anyone know of a station that sells non-ethanol gas? Has anyone tried the premium from the Shell gas stations and are currently using it?
 
now this threads starting to get somewhere.

tuning issues. firstly. mount the carb solidly. if its buzzing or shaking around, the fuel will froth in the bowl. you cannot tune it if its doing that. nylon ties arent really up to the job. some type of bracket, or get someone to weld you up a new adaptor from reeds to carb flange. scavenging say, the bend from some bmx handlebars should get you the clearance AND be the right size. no point port matching one side if the other side lets everything down. one, smooth continuous piece. let the carb work properly!

mikuni and keihins have one thing in common...there are soooo many options available besides just jets! mainly needles... different lengths, thicknesses, tapers... really really complex to get right but a sheer joy when they ARE right!

i havent read anywhere anything about doing plug chops in this thread...? get a new, ngk b(r)5hs or similar. can change to a 6 or 7 later n, but 5 is good for plug chops and most riding.

the carb tuning link already posted and a few others are the best things to read, otherwise i am just repeating them, so i wont. other than, start with the main jet, and find the pdf of jennings "2 stroke tuning"(google...pretty common) and read the part about carbs. one important part is to make sure the needle jet is big enough before doing ANYTHING. pretty simple... remove main jet(yep, take it out), needle on middle clip(if it has one... a lot of keihins use washers and a fixed needle.) then try to start it.

if it wants to rev at all when the throttles opened...the needle jet needs opening up. if it bogs down, splutters and dies with a wet plug...GREAT! you can go back to jetting.


ethanol smethanol... while i wont run it anymore, simply because my road bike seized up whilst i had a tankful of it...the condition was pre-existing and not caused by fuel.


despite the 11.5:1 compression ratio...it revs harder on 91 and 95 compared to 98.

there is nothing that can be damaged by ethanol in these engines.

using high octane fuel is pointless, a waste of money, unless you enjoy running full throttle at very low speeds (lugging up steep hills with too high a gearing) or have a ridiculously high compression ratio.

maybe once you fit a decent expansion chamber, then you can use the expensive stuff, but for general use... low octanes produce more power.
 
U can order it on eBay there are many brands I last bought Torco 118 most hi compression motors will hardly run on pump gas
 
U can order it on eBay there are many brands I last bought Torco 118 most hi compression motors will hardly run on pump gas
It's really expensive but you will not get the full potential of your motor without it
 
now this threads starting to get somewhere.

tuning issues. firstly. mount the carb solidly. if its buzzing or shaking around, the fuel will froth in the bowl. you cannot tune it if its doing that. nylon ties arent really up to the job. some type of bracket, or get someone to weld you up a new adaptor from reeds to carb flange. scavenging say, the bend from some bmx handlebars should get you the clearance AND be the right size. no point port matching one side if the other side lets everything down. one, smooth continuous piece. let the carb work properly!

mikuni and keihins have one thing in common...there are soooo many options available besides just jets! mainly needles... different lengths, thicknesses, tapers... really really complex to get right but a sheer joy when they ARE right!

i havent read anywhere anything about doing plug chops in this thread...? get a new, ngk b(r)5hs or similar. can change to a 6 or 7 later n, but 5 is good for plug chops and most riding.

the carb tuning link already posted and a few others are the best things to read, otherwise i am just repeating them, so i wont. other than, start with the main jet, and find the pdf of jennings "2 stroke tuning"(google...pretty common) and read the part about carbs. one important part is to make sure the needle jet is big enough before doing ANYTHING. pretty simple... remove main jet(yep, take it out), needle on middle clip(if it has one... a lot of keihins use washers and a fixed needle.) then try to start it.

if it wants to rev at all when the throttles opened...the needle jet needs opening up. if it bogs down, splutters and dies with a wet plug...GREAT! you can go back to jetting.


ethanol smethanol... while i wont run it anymore, simply because my road bike seized up whilst i had a tankful of it...the condition was pre-existing and not caused by fuel.


despite the 11.5:1 compression ratio...it revs harder on 91 and 95 compared to 98.

there is nothing that can be damaged by ethanol in these engines.

using high octane fuel is pointless, a waste of money, unless you enjoy running full throttle at very low speeds (lugging up steep hills with too high a gearing) or have a ridiculously high compression ratio.

maybe once you fit a decent expansion chamber, then you can use the expensive stuff, but for general use... low octanes produce more power.
Thanks for the info. We should talk more about these carbs and needle jets and pilot jets and there's another jet but can't think of name.

I've basically got the main jet solid, just a little confused about the other jets. Like how to set them, where to get them and do I really need to.
It's strong off the line and I think mid range and kinda loses it at the top not as much as before tho.
 
Sorry you couldn't get that leak figured out. Also I'm pretty sure they put the spacer in so there reed setup doesn't look exactly like the design they ripped from arrow lol. When I get mine altogether that crude aluminum block won't be there. And yes less space between the carb and piston equals more crank case psi, or so I've read seems logical. Also sir headsmess it's a possibility that ethanol and aluminum or aluminum alloys might not like each other. I fix a lot of mowers and have seen two brigs carb bowls with pin holes from what I've been told was ethanol corrosion. But I've no proof that that's what caused the holes. I still have one of the bowls just cuz I couldn't believe it lol. The guy at the local mower parts place said he knew for a fact ethanol eats aluminum, but idk.
 
Well just got 91 octane from gas station, couldn't figure out if it has ethanol in it or not. It was an older station so hopefully not.
Might have to do some more tunning to get her to sing up hills like she should. Drives me crazy just go up the hill:(
 
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