Super Dio ZX AF28 and other Dio scooters

[Dakine]

Isnt your pilot cooling things off when you let go the throttle? So if your temps are raising when you let go wouldnt that mean to up the pilot?

[sanjuro]

Greetings: Don't wish to 'jack your thread, but since we have the same carb I'll share my recent experience.

Dude, no worries at all. I'm learning a lot from this.

[Wheelman-111]

Greetings:

I have spares from 135-165 if you need. LMK and send me an address if so

[sanjuro]

Don't worry, I've got a ton of main jets. Thanks for thinking about me.

[Wheelman-111]

Greetings:

Quoth Dakine:

Isnt your pilot cooling things off when you let go the throttle? So if your temps are raising when you let go wouldnt that mean to up the pilot?

When you put it that way, it's embarrassingly obvious. I guess I was fixated on optimizing idle mixture, not thinking about closed-throttle run-down. With a #15 and 1.5 turns out it idled fine. Still not sure exactly how a 22.5 plus 2.5 turns out makes things better, but it's obviously spiking less hot. Thanks for giving me something to ponder. I'm ordering a 27.5 manana. Bigger still?

[sanjuro]

I just checked my spark plug, and it's slightly oily and a little darker than brown. My current jet settings are 35 slow and 160 main. I have a 37.5 slow jet I'm going to try as-soon-as it gets here either Monday or Tuesday. If it doesn't foul the plug and/or bog, I'll go up to the 40 and experiment.

Wheelman, you might even try the 35 slow jet.

[Wheelman-111]

Greetings:

I may do that. Where are you getting yours? Need fast delivery... My biggest ATM is 22.5.

[sanjuro]

Where are you getting yours? Need fast delivery... My biggest ATM is 22.5.

Haha, I got mine from Beatrice Cycle like you did. I just checked the tracking on the package, and the jets should be at my house Monday afternoon.

I can send you a 30 to experiment with. You want me to mail it to you?

[Wheelman-111]

Greetings:

PMed. It'll be interesting to see how the idle mixture screw behaves.

[bakaracer]

I just checked my spark plug, and it's slightly oily and a little darker than brown. My current jet settings are 35 slow and 160 main. I have a 37.5 slow jet I'm going to try as-soon-as it gets here either Monday or Tuesday. If it doesn't foul the plug and/or bog, I'll go up to the 40 and experiment.

Wheelman, you might even try the 35 slow jet.

If the engine starts to load up when at idle for a little bit,the pilot is to big.Don't for get to make sure the main is not getting to fat because of the overlap from the pilot.

[Wheelman-111]

Greetings:

Thanks Bakaracer! I planned on dropping the needle down when I get my bigger pilot jets if I encounter the phenomenon you described. If that fails, I'll swap in the 170 for the 180 and raise the needle back a click or 2.

Right now I have the 22.5 in there with the needle up, and although the heat spikes are less severe, I'm waiting for the bigger pilots before I do any more testing. Once bitten... The raised needle makes acceleration a bit blubbery once more anyway. So we're really tuning for two separate but related engine events: On-throttle and Off-throttle. It's confusing and complicated. Anyone seen my Excedrin Migraine Formula?

[sanjuro]

If the engine starts to load up when at idle for a little bit,the pilot is to big.Don't for get to make sure the main is not getting to fat because of the overlap from the pilot.

Cool, I was wondering how I would know if the pilot jet was too big.

[Wheelman-111]

Greetings:

Quoth Bakaracer:

If the engine starts to load up when at idle for a little bit, the pilot is too big... (Emphasis added.)

Do you mean carbonize, or just starts to slow in RPM?

[bakaracer]

load up meaning when you get on the throttle from idle,the engine starts to studder like its way to rich and you have to give is more gas to clear it out and the exhaust starts to smoke real bad from to much gas.when it does that,that means the plug is almost at the point of fouling out.

[Wheelman-111]

Greetings:

Thanks, Bak! So the mixture would be too rich to gain RPM quickly until the throttle slide opens wde enough to let enough air through?

The best choice is to install the next smaller pilot then. But if that wasn't an immediate option, a lower needle position, and later opening of the Main jet would improve things a bit?

That was my observation with the 22.5 at least. Big 180 main, though. I'm surmising that 135-150 compression is tough to tune.