I am stumped!

[houg]

dirt in carb   drain or clean your carb

[Mr. Paul]

Thanks everyone for the replies. I really, really appreciate the feedback. I have the problem solved. The carb jets were clean, the fuel flow seemed good, the manifold was not leaking. I checked the plug. It was in good shape, except it was white. It wasn't white before, but I just changed to a non-iridium. I checked the fuel mixture screw. It was turned almost all the way towards lean! I backed it up 2 1/2 turns and all is good now.  Now that I know, I feel as if I should have known. I think.

[CROSSBOLT]

Cannot argue with success, Mr. Paul, but idle mix screw affecting beyond idle throttle seems illogical (Spock again!).

Karl

[Mr. Paul]

Cannot argue with success, Mr. Paul, but idle mix screw affecting beyond idle throttle seems illogical (Spock again!).

Karl

Darnit Jim, I'm a scooterist, not a doctor     Gimme some feedback here Karl; The idle screw on the Helix controls how much fuel goes into the intake during low speed operation but, being independent of the enrichment circuit, does not cut fuel to this port during high speed. Therefore, the high speed operation of the engine relies on the assistance of the low speed idle system to add to the overall enrichment of the combustible mixture. If you cut the fuel to the low speed system, it would be logical to assume that fuel is also cut to the final combustible product at high rpms.

[tortoise]

I checked the fuel mixture screw. It was turned almost all the way towards lean! I backed it up 2 1/2 turns and all is good now.

Somewhat odd how the pilot/low-speed mixture screw would effect what was described as a mid-range issue?

[CROSSBOLT]

I gotta admit there IS some overlap in the idle and run circuits.......

Karl

[Mr. Paul]

Karl, on the Helix the idle port does not shut off when the high and mid kicks in. It continues to add fuel to the mix. Seems like to restrict the port, would be to restrict the fuel added to the mix at all speeds. I will definitely keep an eye on it. Going to ride it some then pull the plug to verify. I respect your opinions so I am still leaving the option open that I could very well be wrong. Right now it is running great.

[CROSSBOLT]

Wait til I post my diagnosis boo-boo's on another single cylinder engine! You'll never speak to me again!

Karl

[Mr. Paul]

Wait til I post my diagnosis boo-boo's on another single cylinder engine! You'll never speak to me again!

Karl

I will always speak to you Karl, no matter what. Just remember that I am 100% correct, 60% of the time. You have forgotten more than I know. (Hats a compliment)

[CROSSBOLT]

Aw, you say that to all the girls! Except Nireen!

Karl

[Mr. Paul]

Aw, you say that to all the girls! Except Nireen!

Karl

Shhh. She might be eadingrae this.

[DIRKHUNT]

Had similar isses with my Bajaj Chetak
Turned out to be the plug wire

Sent from my SM-G900P using Tapatalk

[Redk]

Wait til I post my diagnosis boo-boo's on another single cylinder engine! You'll never speak to me again!

Karl

Boo-boos ?
I've made a few.
Actually, too many to mention.

1 example only.

Many years ago a friend was upset his car just wouldn't go...  it started quickly, never let him down, but had very little power going down the road.
I drove it, and could not see anything wrong, either.
I suggested the transmission could be bad, which he refused to accept, mostly because of the expense.

That night, a competent mechanic visited, and we went out to look at the car.
Lifted the hood, started the engine, and it lit up like a Christmas tree in the engine compartment !
Bad sparkplug wires.
Mea culpa.
redk

[ole two wheels]

If you suspect Putin, just check with Trump. All the democrats will tell you, they are  in kahoots..
hee hee.


Mac.......didn't say it

[h2ou8n4]

Just a stab in the dark, but two possibilities:
1. I had a big Suzuki road bike that behaved like that and the problem was the ignition coils.
2. Another big road bike, a Yamaha, had a fuel line running from the tank to the carbs that was exposed to engine heat. At a certain temperature, the line would kink resulting in reduced power.