Need help with a 30mm carby

[Peakn 50]

hey guys,
I am about to replace my pistson rings with fresh ones and all new gaskets. But i am having problems with my 30mm carby, i think its a mikuni Replica (Atomik 140cc nitrous) and it is always flooding itself & the choke spring is broken.
but im guessing it is flooding itself because i need to do rings and it doesnt have enough compression.

but i was thinking about replacing my carby with this one,
what do u guys think of this "KEIHIN REPLICA":

NEW KEIHIN REPLICA PWK 30mm FLATSLIDE CARBY CRF PITBIKE - eBay Other Makes, Bike Parts, Motorcycle Parts, Accessories, Cars, Bikes, Boats. (end time 13-Jul-08 20:51:22 AEST)

Help would be appriciated guys

thank you
peakn 50

 

[MasterSpoon]

bike will run like crap
your "30mm" mikuni is more like a 26mm
the oko you want is the 26mm one
KEIHIN REPLICA PWK 26mm FLATSLIDE CARBY KIT 140CC 125CC - eBay Other Makes, Bike Parts, Motorcycle Parts, Accessories, Cars, Bikes, Boats. (end time 24-Jun-08 20:01:38 AEST)

 

[I_THUMP]

Yes I second that. That is the carby u should get

 

[Peakn 50]

yes

but the link i gave you
isnt that carby the same one as u sent me man??
so the link i gave u, that carby is different then the link u gave me (the 26mm carby)
thank alot guys

 

[I_THUMP]

The link masterspoon posted was for the 26mm carby which is better suited to ur motor. The link u posted was a 30mm which is too big for ur motor

 

[MasterSpoon]

the link you had was to the OKO 30mm carbie that is WAY to big for your motor
the link i posted was for the OKO 26mm carbie (4mm smaller) and it is the best one for your motor unless its heavily worked (the picture DHZ has up is for the 28mm but he will send you the 26mm one)

don't be confused by thinking you currently have a Mikuni 30mm as its not a genuine 30mm as its oval bore and is equivalent to a 26mm round bore carbie (eg the oko)

 

[Peakn 50]

I_THUMP
yeah yeah i get what you mean.. BUT isnt the link i sent "30mm carby" bigger and better because its got bigger jets ETC and give my bike some more go?
plus this is probs the last time i want to spent $$ on a good carby
so if i get a new carby i wont a good one whats going last me etc..

cheers

 

[Peakn 50]

Masterpoon
BUT plus this is probs the last time i want to spent $$ on a good carby
so if i get a new carby i wont a good one whats going last me etc..
AND what kind of mods will my bike need to run that carby??

cam?
new valves?
rotor kit?
port and polish ?

 

[I_THUMP]

Bigger is not better if ur motor is not suited to it. I will leave this one to masterspoon who should be able to explain it better coz im just a rider and not a mechanic lol

 

[Peakn 50]

yeah true
cheers for your help I_THUMP =]

yeah i think your right
the 26mm mite be looking goood
but will find out some more info tho

 

[MasterSpoon]

carbies need vacuum to work
imagine sucking on a garden hose, gonna pull a bit of vacuum right, now imagine sucking on a piece of 50mm pvc pipe or something, not gonna happen is it......

to run the 30mm carbie you would need some spastic engine work I would imagine, even the heavily worked (cams, port + polish, valves, ect ect) still only run the 28 as far as I'm aware

If this is the last time you want to buy a carbie then go the 26mm OKO, I run one on my bike (YX140, IRK, cleaned up intake, free flowing exhaust) and it runs really really well, any bigger then the 26mm tho and they apparently have a real bad bog if you open the throttle to quickly.

Don't forget how big is your manifold ? how big is your intake port on your engine ? bigger then either of those is pointless.

 

[MasterSpoon]

btw if you search in the tech section this has been covered many many many times and "Mack" also goes into a little bit of detail on how he tweaks a 26mm OKO to make it run like a 28mm up top yet keep the ride ability of the 26mm down low.

 

[Peakn 50]

yeah yeah
i exactly know what u mean now
i was just getting confused with why not the bigger one
because i thought it would give it more punch
but i know what u mean by when it will just bog with the 30mm
so yeah i wrecken the 26mm is looking good
yeah i not 100% sure, guessing the stock size on the bike ATM
i have a atomik 140cc nitrous: pics if this helps

 

[Peakn 50]

Masterspoon
yeah thanks alot for that mate
yeah i hope the pics help abit the last one u cant really see the manifold but just thought id show u my ride also, thanks

cheers

 

[Peakn 50]

BTW masterspoon
copuld you please give me a link
about the carby in tech talk

cheer