UNI filter question By curiousgeorge (Read 2,513 times)

[curiousgeorge]

Alleyoop, i accidentally stripped the screw that holds the cover over the needle. Any way to get it out still?

[Alleyoop]

Yes, if you have a locking vise grip pliers it makes it easy. But you can try regular pliers and grab it from the side and turn it, once it is loose it will come out easy.
Alleyoop


Watch this VIDEO and notice how he taps the Screwdriver to set the screwdriver in the screw and as well loosen the threads inside and makes it easy to then unscrew it.

[curiousgeorge]

I had already done that but these screws were in there really really good. So the scooter already runs better with new main et and pilot jet in. The old main jet in the original carb was actually a #83 main jet. So do you think i could go up a size then? Or leave it at that and try to put the new needle in? Also i am having a problem with the idle. When i start it it starts for a second and then dies because it isn't getting enough fuel so i have to keep it revved for a little whole before it can run on it's own. Now i tried upping the idle speed but then the idle is wayyyyyy to fast after the engine is warmed up.any suggestions?

[Alleyoop]

How do you know the OLD MAIN JET is a #83?? You told me it was not marked!!

Remember MORE FUEL does not mean more power, the motor can only take so much air and fuel. ONce you reach that point the only way it will take more fuel and air is to put in a bigger piston for more displacement.

So are you saying that if you turn up the IDLE it starts good??
If so then you need to richen the FUEL RATIO MIXTURE that is what your doing when you turn up the IDLE it is opening more of the tiny holes so it can suck out more fuel.
Alleyoop

[curiousgeorge]

The stock jet in the NEW carb was not marked, the stock jet in the OLD carb that i put into the new carb was marked with 83 on it. Ok i will turn the mixture mixture up a little bit more and see if that helps. Cause after bolding the throttle for a a little while it will idle fine.

[curiousgeorge]

Alleyoop I took my scooter for a ride and for some reason its speed has gotten a lot better....idk why but maybe the carb just needed a break in period ? Also I never got the top of the carb off where the needle is because of that screw. Is it important to get that screw off or just let sleeping dogs lie and leave it be?

[Alleyoop]

If it is running good leave it.
Alleyoop

[curiousgeorge]

Ok cool. Thanks so much for your help. Now i just gotta fix my breaks

[curiousgeorge]

So I adjusted my air fuel ratio a little richer. It still requires me to hold the throttle for a little while before it can idle with out stalling. Also if i go to a red light, or stop sign and stop, when i pull the throttle there s a hesitation before it actually pulls off from the light or stop sign. Any ideas on this?

[Alleyoop]

You are going to have to change the diaphgram from the old carb and put it in the new carb.
The needles are different on both carbs. But I really think the #83 is to big for that motor with a Free Flow Filter.
Like I said those scoots usually come with a main jet that is in the #70s.
Alleyoop

[curiousgeorge]

Ok, in the morning i will see if i can get that stripped screw out of the new carb to replace the diaphram. Now is there a better main jet to use? The #80 didn't perform well so what is your suggestion oh wise Alleyoop ?

[Alleyoop]

Hard to say all this is trial and error trying to match air and fuel with the motor. All motors are different and all one can go by is what others found to work for their motors. Actually most with a 72cc Big Bore Kit used a #85 some a #88 main jet and then #90 etc..

One thing you can check is run it and then take the plug out and see how it looks. You can also let it idle for around 10 minutes and then take the plug out and see how it looks at idle.
That helps in determining rich or lean conditions, if it is black and sooty it is running rich if it is nice and clean running lean. Also the center electode if it is running in a good range should be on the brown tan side, if it is WHITE it is running Lean.

So put that other diaphgram in and see how it runs with the #83 in there. Also before you put it in Look at the NEEDLES and see if the NEEDLE FROM the ORGINAL carb is Thicker Or Thinner than the NEW CARBS NEEDLE.

A Thinner needle in a jet will allow more fuel to pass through, while a Thicker needle in the same jet will allow LESS FUEL to pass through. That helps in determineing why one runs better than the other using a specific size jet and helps determine if more or less fuel is needed.
Alleyoop

[curiousgeorge]

Ok i will try that. All though I still haven't been able to get that stripped screw off the carb yet. The pliers aren't able to grab it, I even tried small needle nose like vice frips.

[jct842]

If you stripped the philips grooves out on the screw take a dremel with a cut off wheel and cut a slot in top of screw so a regular screw driver will fit it.

[curiousgeorge]

Worked like a charm! That dremel trick was perfect! So I put in the new diaphram and the only problem left is when I rev it twice and make it go vroom vroom, the rpms drop very low for a second almost about to die and then go back to normal.