I Give Up

[VinceDrake]

If you don't like the messiness, Carb and Choke cleaner works excellent too. Engines like the propellant, and they speed up nicely when they get a little C&C instead of raw air.

Thinking about it further, Mr. Duck has a good point, intermittent electrical short *will* cause igniton break up on these machines. Good idea to check for grounded/melted/poopy wires, while you're in there anyways.

--Vince

[metcalfguitars]

Check the boot on the spark plug. I changed my plug and inadvertently let the boot slide up the wire, away from the plug and it would start cutting out about mid-speed (no tach). I was grounded a few days until I discovered it!
Tim

[chinaguy]

Metcalfguitars sounds very familiar; do you belong to Harmony Central's acoustic guitar site?

[metcalfguitars]

No, but several of my guitars have been reviewed there.
Tim

metcalfguitars.com

[chinaguy]

Well, it's good to know you because you're interested in China bikes, and the fact that you are interested in guitars, as I am, is also nice!

[jshellito]

Originally Posted by chinaguy

Well, as usual, I spoke too soon.

I thought I had everything fixed when I took the carb out and cleaned everything (for the 2nd time) yesterday. I went for a little ride last night and there was a little hesitation when applying throttle, but I thought I could adjust the fuel mix screw to smooth it out. Nope. This morning, I started it up and it breaks up around 3,000 rpm again, all the time.

Now, I'm starting to suspect crud in the gas tank. I guess I'll have to drain it out into something and fill up with fresh fuel. What am I supposed to do with the fuel I drain out? And, another question: I've using regular unleaded in both the bike and the lawn mower. Should I be using mid-grade unleaded?

I have to run 92 min, I tried regular and the bike ran like crap.
Whats the owners book call for?

[chinaguy]

I finally found out that a loose ignition wire was causing the stumbling at about 4,000 rpm. The wiring plug was ok, but one of the wires was loose.

As far as fuel, my owner's manual says "We recommend that the gasoline brand is RQ-90 or over RQ-90." I don't know what that means. I think that regular unleaded is 89 octane, so maybe that's what they are referring to. It stands to reason that these engines would probably run a little better on a higher octane. It might not be a bad idea to use mid price unleaded. I'm not sure; is mid price like 92 octane?

[jshellito]

Originally Posted by chinaguy

I finally found out that a loose ignition wire was causing the stumbling at about 4,000 rpm. The wiring plug was ok, but one of the wires was loose.

As far as fuel, my owner's manual says "We recommend that the gasoline brand is RQ-90 or over RQ-90." I don't know what that means. I think that regular unleaded is 89 octane, so maybe that's what they are referring to. It stands to reason that these engines would probably run a little better on a higher octane. It might not be a bad idea to use mid price unleaded. I'm not sure; is mid price like 92 octane?

87 is reg, 89is plus, 91 and above is super.
Try the super i'm pretty sure thats what you should be running.

[chinaguy]

That's good to know. I've been running 87 octane (regular) in mine. I'm gonna try a higher grade.

[jshellito]

Considering the tank size and the mileage we get, It don't hurt are wallet to much for better gas. I'm just glad my car don't call for super that would REALLY hurt.