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Worth it!

Darryl Cainey

Sir Darby
I received a lot of flak on the forum after posting that I send my Carbs out to Bing for a complete rebuild.
I had them install the alcohol proof independent float kit at the same time for a cost of around $655.

I went for a test ride to check my mileage and I am getting 53.86 mpg imperial.

Wow what a saving!

I was going on 1st reserve at 170 miles before the rebuild now I hit 235 miles before going on reserve.

Works for me!
 
Darryl -

Sounds great! Did you have to do anymore tweaking, like a carb synch, once you got them installed? Seems like they could do some testing at Bing, but in the end, it's how it performs on the bike per what the cylinder wants from the carb.
 
I installed new throttle & choke cables then had a buddy sync the carbs.
Small adjustments were made to idle setting and fuel air mixture.

It runs very smooth now!
 
Glad to hear your Airhead is running good. I think the float mod is worth the $ despite what Snowbum says. FWIW, I had installed the alcohol proof kit many years ago and updated the floats after about 20 years. Last mileage was 44 miles/gallon US which equals about 52.8 Imperial. Carbs were last rebuilt in 2009.
 
For comparison, what was the MPG prior to replacement?

As far as the high cost of the Bing rebuild, I would say that it's not that expensive considering. I remember looking at the photos of the rebuilt carbs. (I looked for, but couldn?t find your original post). They included new brackets, screws, springs, etc. on the exterior of the carb making them look as new as possible. If you added up the cost of those parts, via BMW, they totaled almost $200. Granted that's retail for each individual part, and the rebuild would include those parts at a discount. On the other hand, my experience is that Bing is more expensive on parts than BMW. So, the parts (based on retail costs) including the full rebuild kit is about $400 by my count. That would leave about $200 for the labor, cleaning parts (fluids, etc.), overhead and shipping. Not terribly bad, but most of us probably don't care that some of the exterior brackets show their age as long as they function properly.
 
I have never been one to obsess about gas mileage, I figure it's my hobby and it doe not matter.
When it runs out I fill it up.

I did check the first tank 53.86 mpg Canadian.
 
That's good information, and yeah, that's pretty good economy.

You'll hear no flak from me for using factory experts.

Same with obsessing over gas mileage. I know my airhead gets waaaaay better MPG than my Ford F150, and is running very well, so why sweat it?
 
That's good information, and yeah, that's pretty good economy.

You'll hear no flak from me for using factory experts.

Same with obsessing over gas mileage. I know my airhead gets waaaaay better MPG than my Ford F150, and is running very well, so why sweat it?

Much better than my 1998 F150 too!
 
Darryl , What did Bing do that you couldnt do yourself? Glad your satisfied. Plus they are not a factory rebuild.
 
I think it was me that started the thread. "Sending my bing carbs out for rebuild to ?"

It does sound like a lot of $ but it's the results that we are looking for.
......or maybe we want to "tinker"
The carbs are still on the bike & I'm still wondering which way I will go when the time comes.

Glad your ride is running so GREAT! :clap
 
I too pondered fix 'em or send 'em out. Eventually I decided I had more time than money so I chose the former. I forget how much the kit from Bing cost, but; cleaning, replacing "o" rings, needles, diaphragms, and jets was not all that hard. I don't know what the fuel economy figures are either, but it starts and goes like it aught to (better than it did). I feel good about the work done and if there is a problem I can take it straight to the mechanic because there is a lifetime warranty on the workmanship. But if you want to polish them and turn them into eye candy, that will take greater effort and may well be worth the cost of shop service. I don't have time for too much polish. I also re-built the entire top end so I don't know how much the improvement had to do with the carbs. One of them did have a bad air-mixture screw O ring so that would explain the poor idling prior to the valve seat failing. If you fix it yourself, the better chance of finding a fault that will explain your poor running.







1982 R100T 1992 R100RT
 
I think the price is fine if you're satisfied with the results, sounds reasonable for the work involved to "do it right" and it sounds like they sure did it that way. :thumb

Now where are the photos!?
 
Darryl , What did Bing do that you couldnt do yourself? Glad your satisfied. Plus they are not a factory rebuild.

They had all the parts on hand, many that are not in the standard rebuild kit. I was very nervous about the throttle shaft screws replacement and fitting the new slides.

I wanted to do this after 516,000 miles, I had replaced needles & seat, diaphragms, gaskets and so on, but never a total rebuild.
 
I don't understand the mind set of people who would give you flack for doing that. Your bike, your carbs, your time, your money, your choice. If / when the day comes mine need rebuilt, I don't know if I'd try it myself or send them to Bing. I was a little suprised at how much it cost, but they look terrific, they're performing great, you're pleased with the work...so good deal. Thanks for sharing the information and photos with the rest of us. I found it useful.
 
Darryl: I worked out your cost per mile to $.00129, so I think you did OK. :)
 
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Hmmm....I actually rebuilt and sync'ed my own carbs on my '83 R80RT. I did not use the new alcohol kit. No ethanol in Michigan. I am getting around 48.5 mpg (US) over a period of about 6,000 miles. Some tanks I get 50+, some around 46 mpg. The problem I first had was getting over the fact that I am getting such good fuel economy and that I must have done something wrong. I rationalize it by thinking I may just have better airflow (lower pumping losses) with a K&N filter and a SITO exhaust. Plus I use NGK Iridium plugs. Plugs look very nice with just a touch of brown at the base and lightly browned 'trodes.

MY PO said he was getting 45 mpg but his plugs were dark and oily looking things.

Let me know what you think of this, but man, I gotta be a happy guy too.
 
Here are my bikes statistics.

1977 R100RS with 517,000 total mileage
at 110,000 miles I transplanted an engine from a 1984 100RS with 6,000 miles

Sito Exhaust, K&N Filter, flow through oil cooler extension oil pan.

Slightly more compression than stock, .040 milled off the heads.

Unleaded valve seats

Thunderchild Diode Board

Very happy with my bike & choices!
 
Bing rebuild well worth it

I had my Bings rebuilt for my '77r100rs by Bing and couldn't be happier. For me, it was accepting my limitations. I can do valve adjustment, PRT seal replacement, etc., but too many small parts in the carbs, etc. After rebuild, I had my mechanic sync. I also have him "fine tune" the point gap and timing. He's been doing it for 30 years, so it's intuitive for him. I've been practicing law for 28 years, so that's intuitive for me. Air heads are simple by design, but when you are in the middle of nowhere motoring along at 80 mph, the last thing you want to be thinking about is a maintenance item you should have left to to a pro. BTW, my carb rebuild cost was $395 U.S.
 
hey Darryl, nice carbs, I am happy your bike is running great. I am curious what Bing might have done to increase your gas mileage. I recently rebuilt my Bings ( 1990 R 100 GSPD, 32 mm ), I had never done this before, but the bike seems to be running good. I figure I am getting about 40 mpg US, I go on reserve around 320. the carbs seemed pretty basic inside, I replaced the main jets ( 135 ) floats ( standard ) float needles , diaphragm, needle jets, and throttle cables, cleaned real good, and put it back together, I had a factory trained tech help me with the carb sync. I am running Heidanu K 60's, and I was getting 38 or so with Metzeler tourance's. ( before rebuild ) I had let my bike sit for some time, and although it ran ok, I knew it could be better, inside there were some gunky deposits. so I have seen a 1 or 2 mpg increase ( although I did go to a more aggressive tire ), was your increase more than that ? thanks
 

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