Super 9 ac air screw in carb ?

[yogi]

Hi guys,

After a few months not on the bike I eventually got it started last week and up'd the jet to a 100, Now before this I was running an 85 and still ran sluggish and spluttery.

Now I rode it yesterday too work and it was very hesitant from the lights and building the speed up.

So whilst it was running at work I tried to adjust the Air screw and there is 0 affect to the speed of the engine ? So this must be where my fault lies ? as I can't compensate for the extra fuel now ?

look forward to your replys guys as usual :-D (very helpful site BTW)

[Shaka]

Sounds like your jet is too big.  Plus the mix screw will only have an effect at idle.  If it has no effect at idle then your idle jet is too big.  Did you do any mods to account for the up jet?  If not then you are definitely too big.  An 85 to a 100 is a very big jump!

[zombie]

Could be the idle jet is clogged. or the passage leading from it. It sounds from your post as if the scoot would not start, and you replaced the main jet! Disassemble the carb COMPLETELY, and clear all the passages w/ carb cleaner, or Brake clean. Either one of them will work. Make sure to blow the product thru ALL the passages. A sewing needle will help if there is something "stuck ". The mix screw will have NO effect if the passage is clogged. Sounds like you are running the low rpm's of the sputter from the main. The idle jet is soo tiny that a small needle is required to get thru it. The mix screw should be removed to assure the passage is clear. I'll bet the 85 works fine if you have no other mods.

[yogi]

Hi guys only real mod is the tecnigas exhaust, Story was I rode it home one evening and it slowly died, So whilst i was stripping the carb the other day I installed the 100 jet.

Another question, on the air screw should there be a rubber o ring at the end or not? as all I have is the small spring and screw?

Typical start too "Mod" it and it never runs correctly LOL it used to pick up instantly.

[zombie]

Ah Ha! Pull the cylinder. I will bet the piston has melted due to the pipe requiring more fuel. The jet should have been done with the pipe. 

[zombie]

Forgot If you have the Kiehein carb there is no "o" ring.

[yogi]

Hi Zombie, thanks for the reply.

Will I need to remove the head and barrell or just the head too see If it's done damage?

If it has then it sounds a good time too upgrade to the 70cc kit and bigger carb 

[zombie]

I had a long post but lost it. you can pull the head, and look around the exhaust port for lateral groves or melted aluminum. that is generally the hottest part of the combustion chamber. I would suggest you pull the jug as well because I have been there done that. My scoot suddenly lost power, needed more throttle, and died. I pulled the head , saw nothing, and went about trying EVERYTHING else to get it running. Finally I pulled the jug to inspect the lower portion of the bore, and saw tint aluminum beads on the crank. I pulled the piston to get a better look, and by accident saw a shinny spot on the underside of the dome. I poured some gas into the piston, and it ran thru like a sieve. . I never would have looked but I ran out of other possibilities. Here are some picts of the piston. they are not too good but you will get the idea.

[yogi]

Cheers for that Zombie, I'm going to whip the head off tomorow and take a look then maybe a full internal strip.

Ive never seen a Piston do that on a Bike .


In a way i'd like to find something like this to have a direction to go with now as it's a shame it's not to it's old self.

Pete.

[zombie]

No troubles Bro, My first post here was that problem! Yours sounded the same.

[wordslinger]

...all this dang 2-stroke talk...i just don't get it...


..wanna play with some valves?

[zombie]

WE know Slinger! It takes you twice as long...

[wordslinger]

WE know Slinger! It takes you twice as long...

..hey..yeah...


...but when i get there...it's spiritual....

[yogi]

Just to drag this old thread up and update really, Fitted the 89 jet back in (one that came with the bike) and it's running alot better, I have full use of the air screw now LOL.

Only problem is I still have the problem of acceleration from the lights as in it bogs down for about 3 secs or so then goes like a train! any ideas or is it likely to still be carb settings ?

Oh and big thanks for the advice again gents, as it's saved me a lot of dosh so far ;-)

[zombie]

You could try dropping the needle down by raising the "e" clip 1 notch. note the result (better/worse) and then go the other direction if it is worse. I would also buy 2 new spark plugs. 1 to install before you even attempt to tune it, then you can do a quick ride of 1-2 miles at all rpm ranges to see how the color looks, and if needed the second can be used to isolate any bad zone in the rpm's. Thanks for posting back too. It does help alot of others. Best to you Bro!