My r90 restoration.

[Airhead Wrangler]

Originally Posted by blaine.hale

Well that brings up something new then, because the mixture is at the recommended 1/2-1 turn out (I usually land around 3/4 turn) on both carbs. Crap. More fiddling tonight.

*edit: The mixture hasn't been touched since the needles were corrected...that's probably why.
*double edit: Fred, I won't be there till later tonight...having a cookout for my work team.

That's just the IDLE mixture. The overall mixture is affected by needle position as well. Your needle is currently in the top the notch (leanest setting)?

[blaine.hale]

Originally Posted by Airhead Wrangler

That's just the IDLE mixture. The overall mixture is affected by needle position as well. Your needle is currently in the top the notch (leanest setting)?

Yup, very tippy top one. Before, it was on the 2nd. Would idle mixture not effect cranking?

[danedg]

Try fitting a new set of plugs.
It's cheap and easy. Might just clear up a few issues.
Most carburation problems are electrical in nature.

[blaine.hale]

Originally Posted by danedg

Try fitting a new set of plugs.
It's cheap and easy. Might just clear up a few issues.
Most carburation problems are electrical in nature.

Haha, appreciate the input but I've probably changed out 10 sets of plugs at this point to make sure I have a new one in every time I make a major adjustment.
Put the points back on, got a new plug. Pulled the carbs and cleaned things and fixed the needles, got a new plug.
When I put a new one in, I'll ride around for a day or two and observe the color and difference. Haven't gotten to do that with the latest adjustments from the past post. I'll be able to get a read on them this weekend.

[Airhead Wrangler]

Originally Posted by blaine.hale

Yup, very tippy top one. Before, it was on the 2nd. Would idle mixture not effect cranking?

Yes, definitely. Go for a ride at least 20 minutes long and then come back and sync your carbs and set your idle mixture. Don't even pay attention to the factory spec for idle mixture. It's really only meant as a starting point to get the bike running. With the bike properly adjusted for normal idle speed and correct mixture when hot, the bike should not start without choke and should not idle by itself without choke until you've ridden for a good 5-10 minutes.

[blaine.hale]

Quick question, while I'm in the shop. When they (Haynes) talk about carb needle position, they say 1st from the top on the r90. I assume that means the top of the actual carb, furthest away from the jets? The shortest end, basically.

[blaine.hale]

Originally Posted by Airhead Wrangler

Yes, definitely. Go for a ride at least 20 minutes long and then come back and sync your carbs and set your idle mixture. Don't even pay attention to the factory spec for idle mixture. It's really only meant as a starting point to get the bike running. With the bike properly adjusted for normal idle speed and correct mixture when hot, the bike should not start without choke and should not idle by itself without choke until you've ridden for a good 5-10 minutes.

If that's the normal expectation than it definitely is doing that now. (meaning it won't maintain idle or full power for 10 or so minutes.)
Right now, I believe it's running too rich, which is weird, given that if I lean it any more, I get some back fire.
Last I checked, the plugs were getting a bit black and on my ride this morning, it's pretty hesitant on that first 1/4 of a throttle twist (the idle jet.) Once you're over 1/4 twist, the power kicks in.

[blaine.hale]

Just a teaser of the Hoske pipes. I'll get a video of the sound up soonish...I'd like the tuning to be sorted before embarrassing myself with a video.

[blaine.hale]

Do you guys run bp7es or bp6es for NGK sparks? I know the 7es is a cooler plug and the 6es is recommended, just checking.

[disston]

Originally Posted by blaine.hale

Quick question, while I'm in the shop. When they (Haynes) talk about carb needle position, they say 1st from the top on the r90. I assume that means the top of the actual carb, furthest away from the jets? The shortest end, basically.

None of the R90/6 carbs, 64/32/11 & 12, use the top or number 1 position for the jet needle setting. All of the R90/6 carbs are set at notch number 2 according to the Bing manual.

You might find this interesting, I did, none of the CV carbs on any models for any years of the Airheads use the #1 notch on the needle. A couple, only two, use notch #4. And all the rest are #2 or #3. Some of the slide carburetors use notch #1 so this applies to CVs only.

The idle mix starting point is 1 turn out.

I find the Bing carbs temperamental but I have found most carbs to be that way all my life. I have the best luck with setting carbs to factory recommendations and from there I might make small changes and adjustments but after one or two changes or adjustments if not running right I find it best to go back to factory settings.

Somebody said yesterday I think, Most carburetor problems are electrical in nature. Or something like that. Truer words were never spoken.

[blaine.hale]

The Haynes manual is quite wrong on all of the above haha. I'm way more inclined to believe the 2nd north than the first. Its just running really wrong on the first notch. I was scratching my head when I read that in the Haynes...about 5 times to assure I wasn't crazy. I need to grab the bing manual.

[danedg]

Originally Posted by blaine.hale

Just a teaser of the Hoske pipes. I'll get a video of the sound up soonish...I'd like the tuning to be sorted before embarrassing myself with a video.

Where's the choke cable?

[blaine.hale]

Originally Posted by danedg

Where's the choke cable?

You mean that dead weight? I chucked that thing a couple years back and just flip the levers up on the carb bodies. Extra effort but it looks nicer. The only thing I don't like is riding with choke on then having to reach down and turn them off real quick or skillfully.

[disston]

The Bing manual is truly one of the best values in Airheaddom. You pay almost $50 for the Haynes and the Clymers, each. And have to fight them constantly. But the Bing manual is nothing like that. It's today only $11, includes shipping, and contains a wealth of information. OK, so it won't help you rebuild the forks or the transmission, but it's still a good deal.

[blaine.hale]

Originally Posted by disston

None of the R90/6 carbs, 64/32/11 & 12, use the top or number 1 position for the jet needle setting. All of the R90/6 carbs are set at notch number 2 according to the Bing manual.

You might find this interesting, I did, none of the CV carbs on any models for any years of the Airheads use the #1 notch on the needle. A couple, only two, use notch #4. And all the rest are #2 or #3. Some of the slide carburetors use notch #1 so this applies to CVs only.

The idle mix starting point is 1 turn out.

I find the Bing carbs temperamental but I have found most carbs to be that way all my life. I have the best luck with setting carbs to factory recommendations and from there I might make small changes and adjustments but after one or two changes or adjustments if not running right I find it best to go back to factory settings.

Somebody said yesterday I think, Most carburetor problems are electrical in nature. Or something like that. Truer words were never spoken.

Would this happen to be the manual? (you're correct about no carb using position number 1)

http://ebookbrowse.com/bing-carbs-pdf-d346821589