No slide return springs

[Cinciride]

The good news is, I have finally started by carb rebuild.  The bad news is I realized both my diaphragms were torn, right at the insertion into the diaphragms support ring.  I had already ordered the needles and needle jets.   :-?

The other thing I realized as I was tearing them down is there is no slide return spring.  I pulled off the top of the carbs and there is no spring between the cap and the top of the slide.  When I look at the parts microfiches and on line videos of bing rebuilds, they have springs between the slide and the carb top, above the diaphragm.

Is it normal for there to be no spring on an R65?  I do not have flat top carbs.  They are definitely the dome top with the small circle on top.  I am guessing this is normal as I have never opened the carbs before.

Any experience is appreciated as I am placing a second order for carb parts and would like to order the springs if they are supposed to be there.  

Cheers,

Colby

[Bob_Roller]

There should be a spring in there .

Just so we know what carbs you are working on, there is a number stamped into the vertical flange of the carb at the front .

Should read something like this : 65/32/325 .

[Cinciride]

64/32/304 and 64/32/303.  

If these carbs have been opened it was prior to 1989, and they have had around 30K miles put on them since that time.  It is kind of weird.  

Thank you for your quick response.

[Cinciride]

By the way.  The forum folks were like right.  My bike had symptoms of tuning rich.  The f?oats were brown and are getting replaced.  On of the needles is wiggling in the slide.  Th needle and needle jets are also getting replaced.  Thanks again for everyone's advice and experience.  

Colby

Any advice on removing the needles _  grab and tug ?  That is what counsel recommends, but there is quite a bit of resistance.

[Bob_Roller]

Try pulling the needle out and rotating it, the needle should come out a bit maybe an eigth of an inch or so, then rotate it and pull down again to get it free of the retaining clip  .

[Cinciride]

Will try that.  Annum idea how should I expect the bike to behave with a slide spring in there versus without the spring?

[Cinciride]

needle is out.  [smiley=bmw_smiley.gif] turning while pulling was the key.    

Carb is disassembled currently.  I have not removed the idle jet yet, but given the amount of crud in the main jet channel, I am going to replace that too.  The choke and the throttle shaft look like they are the only two parts being spared a rebuild.  The choke works fine and looks easy enough to disassemble at a later date if I develop problems.  The throttle shaft has no signs of problems currently (no play with springs off), and I do not feel like peening screw anytime soon.  

FWIW, Tech support at Max BMW got back to me with some BING diagrams based on my carb numbers.  There are no springs in the diagrams from Bing.  Curious.  

Rebuild pics and log to come once I get my parts in to start the process.  

Cheers,
Colby

[Barry]

We know for sure flat tops don't have springs but I have also heard of some dome tops being supplied without springs. If you have the carb type number check below for a full specification. Not sure if it will mention springs or not but it will give you every other spec. Springs help to make sure the slide is fully shut when it should be and also may help if you have a flat spot when cracking the throttle open by delaying the rise of the slide which then momentarily increases the vacuum over the needle jet to richen the mixture.

http://www.bingpower.de/english/service/einstellblaetter.html

New O rings definitely but the only jet that actually wears is the needle jet so the others are not usually replaced unless they are damaged in some way or won't clean up.

[Bob_Roller]

Here's an exploded view from the Bing site .




http://bingcarburetor.com/pdf/MOTORCYCLE%20CV%20EXPLODED%20VIEW.pdf

[montmil]

... On of the needles is wiggling in the slide.  Th needle and needle jets are also getting replaced...

Colby,

Expect the needles to 'jiggle" a bit as that's the normal fit. I would investigate the needle that's not a wiggler. The tapered needles and the needle jet itself will wear due to the near constant up n' down motion.

Note the small cir-clips that anchor the needle in the slide. I found an odd variety of these clips in the two pairs of Bings I've rebuilt. If you're ordering up parts, buy a few... just in case. One other thing. Note the diagram shows three different needle clips styles. I have a pair of clips that do not fit my Bings. Confirm your carb's cir-clip configuration with the Max parts dept before placing your order. They are cheap enough but if they don't fit, it delays the carb work; as I so well know.

Monte