Question re Replacing Diaphragm on Bing Carb

[Crossrodes]

I have a '79 with flat top Bing carbs.  It's shown on the parts fiche for my bike.  For the life of me I can't figure out how to remove and install the new diaphragm.  If anyone with a flat top carb has done this with this carb could you please tell me how I do this.  

The slider has what appears to be a big plastic "O ring" on top.  The inner part of the diaphragm sits under this "O Ring."  It appears that I somehow have to remove the "O ring" but it is held in place by what appears to be a collar that appears to be part of the slider body.  It may be that this collar is threaded inside but I can't move it.  

Anyone done this that has the answer?

[Bob_Roller]

There's a plastic ring that needs to come off, to get the diaphragm off .

I think you need to warm the ring up with a hair dryer, or something similar, to make it a bit more pliable .

Rob Valdez has done this with his carbs, from what I can remember, the plastic ring is not widely available here in North America .

Hopefully he'll see this and get you the info you need .

[Crossrodes]

Bob, from what you remember was Rob able to reuse the plastic ring after it was removed with heat?  I have to call Bing on Monday so if I need them I'll order them at that time....Believe it or not I found that I had no float needle in this carb.  How it ran I'll never know.  I don't recall any flooding problems and never smelled gas.

[Crossrodes]

Bob, problem solved.  I decided to see if I could pry the plastic ring off with a large bladed screwdriver.  It popped right off...no heat required.  So then I fit the new diaphragm carefully and popped the ring back on using the palm of my hand...No problemo.

It's amazing what you can do with a little help from your friends.  Thanks Bob.

Mike

[Rob Valdez 79 R65]

Mike,

Sorry I didn't see this one till now.

You did right - pry it off.  I reused mine until one wouldn't stay in place any longer.  By then, Bing Agency USA was selling the rings.  You should call and buy a couple for the future.  They are not expensive.

The man at Bing suggested I boil the ring for a little while to make it go in place easier.  I did, but I don't think it made much difference.

[cephas1981]

Mike,

Just make sure you put the ring on so the smooth side is facing up.  This holds the diaphram in place more secure than the other way.  I learned the hard way when I started to hear a whistle and loss in power.  I found I had the plastic piece smooth side down and the diaphram wiggled out from underneath it allowing a leak.

[Rob Valdez 79 R65]

Mike,

Just make sure you put the ring on so the smooth side is facing up.  This holds the diaphram in place more secure than the other way.  I learned the hard way when I started to hear a whistle and loss in power.  I found I had the plastic piece smooth side down and the diaphram wiggled out from underneath it allowing a leak.

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