Genuine mikuni help!!

[WillMatrix]

I ordered a mikuni carb from studz racing and it came with different jets that I was instructed to install. I’m having issues with high RPM and my engine won’t stay on with the choke off. Soon as I take off the choke it dies unless I’m continuously rev it. Any ideas or help? Do you think I need to change to bigger jets?

 

[Denny]

Yup, and a little higher idle to boot.

 

[WillMatrix]

Yup, and a little higher idle to boot.

I’m feeling air around the intake but I’m sure the o-ring is seated correctly on the adaptor. Should I add a gasket between the adaptor and carb?

 

[Denny]

That may be your whole problem right there, a vacuum leak. Make sure it is sealed up good.

 

[WillMatrix]

Ok so I just tried to adjust it again and the O-ring is sitting perfect from what I can see but I’m still feeling so much air escape by it. Should I try a gasket in between the carb and manifold?

 

[Denny]

Gasket or a little bit of silicone.

 

[madprofessor]

Always smear a thin bit of silicone sealer, I use food-grade, on all O-rings where possible, keeps them from bunching during tightening.

 

[WillMatrix]

Gasket or a little bit of silicone.

Ok I’m going to buy some gasket paper and give it a try. I’ll still run the intake across some sandpaper. I never thought I would have a sealing a gasket issue smh

 

[WillMatrix]

Always smear a thin bit of silicone sealer, I use food-grade, on all O-rings where possible, keeps them from bunching during tightening.

You haven’t steered me wrong yet so I’ll run some RTV gasket sealer on it

 

[madprofessor]

I’ll run some RTV gasket sealer on it

That RTV is Room Temperature-----something or other, means once exposed to the air it'll set up. Don't use stuff that requires engine heat or otherwise to set right.

 

[WillMatrix]

That RTV is Room Temperature-----something or other, means once exposed to the air it'll set up. Don't use stuff that requires engine heat or otherwise to set right.

So I can use it? The gasket maker in the grey tube?

 

[Denny]

The black adhesive sealer is better.

 

[WillMatrix]

The black adhesive sealer is better.

Any reason you say it’s better?

 

[Denny]

Yup, because it is an adhesive also. Less prone to blow out.

 

[WillMatrix]

Yup, because it is an adhesive also. Less prone to blow out.

So just update:

I used the gasket paper and it made a world of difference! I have to make another gasket from the predator to the intake because the one it came with doesn’t fully work and allow it to seal. Also, I had to figure out which way was “choke on, choke off”. Once I narrow out the air leak I’ll give another update

 

[Rat]

The black adhesive sealer is better.

That's why I prefer the slightly heavier Blue cellulose roll gasket stuff. It it has an adhesive impregnation that bleeds out and glues it to both surfaces with heat and pressure. Never had it blow out on me except the one time I tried to double layer it on a 2t engine

 

[Rat]

So just update:

I used the gasket paper and it made a world of difference! I have to make another gasket from the predator to the intake because the one it came with doesn’t fully work and allow it to seal. Also, I had to figure out which way was “choke on, choke off”. Once I narrow out the air leak I’ll give another update

Predator intakes (or any engine) require on every intake part mating surface that doesn't have an o'ring.
Even those that use an oring benefit from gasket paper if a proper replacement ring cannot be gotten for an old tired flattened ring