Bing diaphragm change question

This looks pretty straightforward, but I have one question in which the Clymer manual is unusually silent:

Do I really need to pull the carbs to change the diaphragm? It looks like the top cover is all that really needs to come off to get the assembly out and, quite frankly, this is one reason I got rid of a Honda Shadow in favor of an Airhead. Those (Bing) babies are just hangin' out there begging to be worked on without a fuss.

If you can get the throttle and choke cables off without moving the carbs ... go for it.

Hi,
I sold my last airhead in around 2000, but I have changed many diaphragms without removing the carbs from the bike. Disconnect everything between the top and body of the carb - screws, cables, return spring. Lift off the top. Remove the diaphragm and piston. Unscrew the old diaphragm and attach the new diaphragm, making sure the bulge in the diaphragm fits into the depression in the piston. Replace the diaphragm and piston, making sure the needle goes easily into the jet and the bulge in the outer ring of the diaphragm fits into the depression in the carb body. Replace the screws, coating the threads with a slight amount of anti-seize. Reattach the cables and the return spring. Start the bike and go for a ride - 10 miles is good. Now adjust the carbs, if necessary.

Definitely possible, especially easy if you have the slot connectors on the throttle and choke (enricher) cables. And of course carefully remove the choke spring from the top. If you have a nut to hold the choke cable onto the lever (and one for the throttle), its a bit of a pain, but could still be done. If you get a chance, might want to consider switching over to slot mounts.

It might be useful (next time you have the carbs off to squeeze the lower end of the choke spring bend such that it is (essentially) captive on the choke lever. That way, if you pull up on the top end, gently with needle nose pliers, the spring doesn't fall off.

I am sure it could be done.

The carbs are not that difficult to remove. Depending on the carbs and the diaphrams, it is fairly easy for the diaphram to shift slightly out of position as you install the dome. When I replace them like to operate the slide several times and examine the slide alignment to make sure everthing is in the proper place. I expect there are many methods that work. Good luck.

So when can I expect you at the shop to tweak the carbs after you're done?

It would be nice if you can get the tops off with the carbs in place. Be advised that the slotted screws can be difficult to break loose. The last time I did a set of carbs, I ended up having to put them in a vise with the float bowls on and strike the screws with an impact driver and a hammer to make them release. If you have to resort to this kind of operation, be sure to cushion all contact points with folded up rags.

woodnsteel said:

It would be nice if you can get the tops off with the carbs in place. Be advised that the slotted screws can be difficult to break loose. The last time I did a set of carbs, I ended up having to put them in a vise with the float bowls on and strike the screws with an impact driver and a hammer to make them release. If you have to resort to this kind of operation, be sure to cushion all contact points with folded up rags.

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and then replace the screws with stainless steel with never-seez

manicmechanic said:

So when can I expect you at the shop to tweak the carbs after you're done?

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I not sure when I'll be in the neighborhood, but it will be high on my list when I get there.

manicmechanic said:

So when can I expect you at the shop to tweak the carbs after you're done?

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Well, it mighta' been today, but ...