Rick has a wiring harness for me, that should make life easier.
It looks like you have two VDO gauges in place of the stock MotoMeter ones. So you'll still need to make 2 "Y cables" to split the Return (Brown wire) at both gauges, and then construct the fuse holder as recommended for the Clock.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
Rick is going to sell me the whole wiring harness for the front of the bike which includes the signal lights as well. Sadly it's backordered right now.
Got the carbs back on and got hit out of the basement with a little help. Now I just need to do the carb adjustment and balance the carbs.
Right now I am in the middle of getting it insured and registered. I'm about to pull my hair out dealing wth the woman on the phone with insurance. English is not her first language which makes it more challenging and I'm pretty sure she's never had someone put up 4 bikes at the same time before either.
Onward and upward!
Its now registered to me so I guess it's officially in my stable.
It fired right up but spun up to redline pretty quick. I dialled back the idle screws a bit and now it doesn't want to start again despite that being the only adjustment I made. Slightly frustrating as the carbs is the last thing before being on the road!
I will assume that there is a choke lever on the left side of the handlebar. Confirm that the action of the enrichment levers on the inboard sides of the carbs is actually working in concert with the choke lever. There is a splitter called a Bowden connector that transfers the action of the choke lever to the enricher cables that go to the carbs. It's sort of a 1 into 2 cable transfer device. If the Bowden is not fixed to the frame, the cable action can be compromised.
Another consideration is to make sure that the enricher take up jets in the bottom of the float bowls are clear. You are looking for a column cast in the float bowl that corresponds with a brass tube that protrudes from the bottom of the carbs. The jet in the bottom of the column can get blocked with crud. When this condition exists, it can seriously degrade the cold start function. Have you ever heard an Airhead that sounds like it is running on 1 cylinder when it first starts?, that is usually the cause. When functioning properly, the enrichment system should supply sufficient fuel to start the motor with maybe a slight blip of the throttle when it tries to fire.
former Airmarshal, IL.
I will double check the cable activation and the jets should be all good form the rebuild. I tried to make sure all of them were clear and good.
Another consideration is to make sure that the enricher take up jets in the bottom of the float bowls are clear. You are looking for a column cast in the float bowl that corresponds with a brass tube that protrudes from the bottom of the carbs.
All Airheads seem to require the action of a "choke" to start. That is to say it is mandatory. On the stock Bings, this action does not shut off the air, as in a standard carb choke system, but rather opens a gate and floods the intake with raw fuel. Trouble with "cold starting" on an Airhead usually boils down to 3 issues...
• The enrichening jet in the bottom corner of the float bowl on 1 or both carbs is clogged. Make sure they are both clear by twirling a toothpick thru the small orifice.
• The #45 slow speed jet is clogged on 1 or both carbs. Make sure they are both clear by twirling a toothpick thru the small orifice.
• A previous owner has disassembled the carbs and re-assembled them incorrectly. The "enrichener" rotor discs under the side covers look identical, but they are not. There is a Left and a Right disc. When these are reversed, starting becomes very difficult. Some models have the discs labeled L & R, but my understanding is they are not all this way.
Hope this helps.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
I did a full carb rebuild, my first time into Bings so I could have made mistakes. I can see that the cable sare adjusted to fully activate the choke.
I just did another test and it will fire using quick start but will not stay running at all.
When I first tested it after the rebuild it fired up and ran straight up to redline. The only thing I touched was the idle adjust screws to back them out a bit and now it won't fire.
I did just pull the carbs off to have a quick look at the butterflies, both of them sit open a crack with zero input from the idle screws. I did set them according to the manual.
I'm stumped! So close!
Well Mike, it might be time to contact your Airmarshal to see if he can find someone to put an extra set of eyes on it with you. Where are you located?
former Airmarshal, IL.
I agree. It does sound as if your issue is in the carbs. But you've provided zero photos, nor have you responded to my initial input, so simply using logic...
► The fact that the engine zoomed to full RPM can only mean that the slide and/or the butterfly is set (or held) too far open. Primary thing to check would then be that there is MANDATORY free play in the throttle cable outer housing. Start with a generous free play like 1/8" as measured at the top of both carb bodies.
► Then, to start the engine, each slow speed jet must be clear and each pilot screw should be set to 1-1/2 turns out.
► For the enrichener circuit to work the discs must be in their correct side, and it is MANDATORY that the orifice in the bottom of both float bowls be clear. The specific orifice shown below...
• Modern carburetors are extremely precise instruments and you must work on them with the care and precision of a watch repairman.
• The age of your fuel also comes into question. If your ethanol fuel is over 6 weeks old, pour the contents of the BMW's tank, lines and carbs into your automobile's tank and go buy new fuel.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
Funny James, I'm my local Air Marshall and currently I'm the only person in the Club here. Very few people with good airhead knowledge here.
Richard, I'm not sure which initial input you are referring to. As for photos I don't think there's anything that a photo will show.
That parts are definitely correct to each carb as I worked on them totally separately. I definitely checked the float bowl orifices were clear. I went over each jet etc twice to ensure all were clear.
Both pilot screws were set to 1 1/2 turns out.
My guess is that the first zoom to max was because the idle screws were turned in way too far holding the butterflies open. As soon as I backed them off a ways it settled down and soon died.
According to the videos and snowbum's info I'm pretty sure I set the float height right but I can pull them off and go over it all again.
Funny I'm doing the exact same thing on my KTM 525.
Many thanks to Richard for posting that picture. That orifice in the bottom of the float bowl is what I am on about.
A good telltale for that is to empty the float bowl and try to fill up just the column in the corner. At a campout, I used brown whisky to dribble fluid in that little chamber. The column would hold fluid when the rest of the bowl was empty. It amounts to a sort of backwards flow test. What you want is for the column to flow freely into the bottom of the float bowl. At the campground I used the wire from a bread tie stripped of its paper. I poked the wire in to the orifice until a bunch of little black crumbs flowed from the column in to the float bowl. Having cleared that orifice, the troubled bike roared to life.
Also, I looked you up on the Airmarshal list on this web site. Is NL Newfoundland? If so, and you are the only Airheads member on your NL membership list, why not try fishing in a bigger pond for an owner/rider to help you in person. Adventure Rider or Facebook, perhaps.
former Airmarshal, IL.
Also, I looked you up on the Airmarshal list on this web site. Is NL Newfoundland? If so, and you are the only Airheads member on your NL membership list, why not try fishing in a bigger pond for an owner/rider to help you in person.
Dang ! I just spent 2 weeks at the Bay of Fundy, Prince Edward Isl, St Andrews area. For a mere $1000 I could have put off my vacation for an hour and looked at your carbs.
Too late now. 🤣
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
Richard, I'm not sure which initial input you are referring to. As for photos I don't think there's anything that a photo will show.
I'm referring to the 3 bulleted points I made in my first post. And now add the 3 arrowhead points and the comment about the age of the fuel to that list.
It's like you're ignoring the bits that you assume are inconsequential. Case in point....
That parts are definitely correct to each carb as I worked on them totally separately. [I assume you mean the enrichener discs]
And I told you...
• Modern carburetors are extremely precise instruments and you must work on them with the care and precision of a watch repairman.
You're basing your comment on the ASSUMPTION that the previous owner put them in the correct carb. Maybe he didn't, maybe the bike would never crank, so maybe it sat until he got tired of looking at it and sold it to you. You don't know anything, because you have not looked for yourself. It is my professional experience that such assumptions will blow up in your face every time. You are in fact Guessing and Hoping they are the same. These actions display no "care and precision".
Things won't improve until you step up your game. That's simply what it takes.
I don't mean to be hurtful, I'm just reporting what I see.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
I've looked at the service receipts from the previous owner and I think the only carb service done was new gaskets for the float bowls, he owned it for 20 years and rode it a lot until the last 8 or so, so I'm guessing the carbs were fine before that. When I first looked at the bike it fired right up even on old gas.
I did the first carb service in memory and it certainly needed it, the diaphragms were toast as well as a lot of dirt on the slides etc. Being totally new to Bings I can totally see that I got something wrong putting them back together such as getting the float height wrong.
I did purposely inspect and clean out the little holes in the float bowls but if I'm going to pull them apart anyway to double check the floats I will certainly do a double check and maybe as you said stick a piece of wire down there to be extra sure.
I do my best to be conscientious and precise as I work on carbs but I know I'm far fro an expert. I was just messing with the FCR carb on my 525 and totally missed getting the little lifter rollers in the slide so obviously twisting the throttle did nothing. Simple mistakes trying to learn new shit.
Ok, I've definitely done something wring as the float bowls are not filling up. I pulled them and checked those ports which were fine. I tried another start and then check the float bowls again and no fuel going into them. Hmmmm...
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