Anybody using a Genuine 30mm Mikuni Carb not a knock off

[dacs57]

Hello!
I want to try a Genuine 30mm Mikuni Carb not a knock off on my Hawk.
The ebay knock off appear to be junk at least mine is.


Thank's

[Megadan]

I have a real VM30 waiting to go on my bike with a ported CRF230 intake, but it is not jnstalled yet.

This would be a bit too much carb for a stock cg250 though. I am only installing it after my ported head goes on.

You could always install the stock crf 230 keihin carb with the crf intake. Those carbs arent cheap though, even used. They are 26mm carbs equipped with an
accelerator pump and are more than enough carb to support a nearly 20hp 4 valve crf230.

Just out of curiosity, what is making your Fakuni "junk"?

[dacs57]

Hello!
My hawk was runimg just fine about two months ago yesterday I went for a ride and at full
throttle it started surging like it need more fuel.
It was working just fine before,so I change the main jet from 115 to 117.5 and it ran great at full throttle but,it started to run bad at 1/4 to 3/4 thottle then for some reason, so I removed my 35 pilot jet and installed a 27.5 then it ran better than ever before and idled better aswell.
Ok I'm happy now.
Today I went riding and it would not even run 5 mpr and spitting coughing and like it was
flooding out.

Thank's

[dacs57]

Hello!
I was asking about the Mikuni because I had notting but, run good then run bad off and on.
Maybe the carb is junk from ebay.
I removed it and took it apart and blow in the ports with air,float look good, put it back on,No help.
For some reason I have to tape the 2.5 by 3.0 in pod filter half way to restrict the air for it to run right ever since i had that carb on it with the jets installed. I live i Dallas tx and altitude is 500 ft.
Hawk has 400 miles on it and the carb has 300 miles on it.

Thank's

[RogerWFarrier]

I was considering going with the Genuine Mikuni but in all honesty the stock Keima carb which is a Kehin clone that comes on the TT250 performs great. After I opened up the exhaust I raised the needle 1 notch and put a 115 main jet in it with the air box snorkel reversed and haven't touched it since. So until it gives me a problem I'm going to stick with it.

[dacs57]

Hello!
Do you think it will work on hawk and the jets are available?
Has any one you know have one on a hawk and you have a link to one?

Thank's

[rjmorel]

Someone mentioned to me about pod filters attached directly to the carb possibly causing turbulence with incoming air. So the gas being pulled up thru needle and jet are inconsistent. A filter and carb with OEM air boot helps straighten air out that would run thru the carb providing better venturi effect then air tumbling thru the carb.??????? Have no idea if this is true but it kinda sorta sounds reasonable.
Dacs57 maybe taping the filter halfway is straightening out the air and providing the needed ram venturi effect so it runs better???
Maybe try and add a straight piece of tube between carb and pod filter and see if it turbo charges the sucker better.
rj

[dacs57]

Hello!
The OEM air boot is the tube from carb to air box?
And if it is what are you using for the air filter?
Some guy using this one
https://www.ebay.com/itm/Angled-Foam...327?rmvSB=true

What you say does make sense.
May carb has a 5in tube to filter.

Thanks

[Megadan]

Ok so you have a lot going on here, so this is what I recommend. Let's start from square one. Also, since you mention a pod filter, I am also going to assume you have an exhaust, or have modified the stock one (full de-cat and baffle removal)

First, Un-tape your pod filter. You shouldn't have to do that on this engine with your setup. Second, the 35 pilot is too big, even for an intake/exhaust at sea level. The biggest I have seen anybody use is a 30, and more people run the 27.5 or a 25 within the altitudes we live in (I am at 1000ft so my jetting will be close to the same as yours).

Anyway... Here is what I recommend. Remove the pod filter, remove the carb, remove the intake from the head.

Start with the intake. Inspect the O-ring that goes between the intake and cylinder head, make sure it is not torn or flattened out. Also check the rubber sections between the two flanges closely, make sure there is no tears or holes, even little ones. If you find either one to be bad, let me know and I can direct you to the right parts.

Next lets start with the carb. First, remove the throttle slide from the cable. Inspect the seal for the cap on the top of the carb, if that O-ring shifted or got torn it will let a bunch of air in. Second, make sure the needle retainer is secured and the E-clip is still in place on the needle. While you are doing this, set the E-clip in the 4th notch (4th down from the top or 1 up from the bottom).

At this point, I would just assume that the carb needs a cleaning again, it may have had some trash come in and clog a passage or a jet. Remove the pilot jet, main jet, and the emulsion tube (what the main jet screws into. Find a small enough wire to pass through the jet orifice holes to ensure they are clear. Spray out all of the passages in the carb, and go back and give them the air treatment again.

Before assembling the carb again, check the float height. The simplest way to do this is to turn the carb upside down and make sure that the seams on the floats are perfectly even with the bowl flange on the carb. Adjust as necessary. Then assemble the carb again, and go ahead and set your idle mixture screw to 1 1/2 turns out from lightly seated - this is located on the bottom of the carb behind the bowl (engine side of carb) and not to be confused with the idle speed adjustment on the side of the carb). Lastly, inspect the O-ring on the back of the carb and make sure it is isn't torn or flattened.

All of this seems tedious, but believe me it pays to be methodical and check everything. What I am attempting to do with this process is eliminate any vacuum leaks and ensuring that every part of the carb is in perfect working order. Eliminate any "wild cards."

Ok, now go ahead and install the intake. Do not overtorque the bolts that secure it to the head. If you get these too tight it will actually bend the flange and potentially cause a poor seal to the head. My suggestion is to get them both finger tight, and then torque them down to what I call "wrist tight." If we are going for a torque value, then I would say 10ft-lbs (typical for most Honda M6 bolts) and no more than 15ft-lbs.
Next, install the carb, again, these don't need to be super tight so the same torque specs can be used here. Also, make sure the cap for the throttle slide is seated securely - again just a good snug up, it doesn't need to be cranked down.

Go ahead and install the air filter as well.

The only other suggestion I can make is to go ahead and double check your valve clearances. It's a little bit of extra work, but too loose or too tight valve clearances can cause running problems as well.

After all of this, and assuming everything is in good working order, go ahead and start it up. You will likely have to adjust the idle mixture a little bit, but with the 27.5 pilot at 1000ft in 80 degree weather I was at 1 1/8 turns out. When the temps dropped I had to open it up to right around 1 1/2, so it should be darn close.

[Megadan]

Originally Posted by rjmorel

Someone mentioned to me about pod filters attached directly to the carb possibly causing turbulence with incoming air.
rj

800 miles last year with a pod filter directly on my Mikuni clone with no problems.

[rjmorel]

On my Honda MT125 2 stroke that I completely got rid of air box and boot I went to Home Depot and found a hard plastic pipe connecter that was close to the right size but bigger then carb and air filter. Then I made some aluminum bushing rings to take up the slop between connecter tube and carb and air cleaner. Use radiator clamps to tighten them together and "bobs your uncle" rj

[rjmorel]

Originally Posted by Megadan

800 miles last year with a pod filter directly on my Mikuni clone with no problems.

That clears that myth up then, must be other problems going on. rj

[dacs57]

Hello!
Wow thats alot of info and it makes sense.
I will check it out more and can you go ahead and send that link a may just get one anyway.
Mr Megadan
Do have a picture of you filter setup or what filter your using?

Thank's

[Megadan]

Originally Posted by dacs57

Hello!
Wow thats alot of info and it makes sense.
I will check it out more and can you go ahead and send that link a may just get one anyway.

Do have a picture of you filter setup or what filter your using?

Thank's

It is a lot of info, but I did it on purpose. There are a LOT of things that can cause issues like yours. I wanted to focus this thread and your troubleshooting instead of having a bunch of willy nilly suggestions that will lead you in circles. The goal here is to go through everything and eliminate as many of them as possible. If you do all of this, and do it right, then one of two things will happen - it will work, or it won't. If it doesn't work, then we can move on to more in depth troubleshooting. Why spend a ton of money on a new carb setup if you don't need to? Just be patient, methodical, and thorough.

I don't have a picture of my current filter. I was running a Uni filter, but it only had a 15 degree angle to it and was contacting the side panel more than I liked, so I switched to one of these guys. https://www.ebay.com/itm/Angled-Foam...JVbSSK&vxp=mtr

It's been working great so far. Just make sure to oil the inner foam filter just like a Uni filter.

[dacs57]

Hello!
I just order one of that type filter this evening it should have by fri... from Amazon.
I will keep in touch with results.
Thank's to all of you for your input.

Thank's