I have been running 36mm Dells on my R90 race bike for 18 months, going to bump it up to 1000cc using info supplied earlier by Dirk from Germany. I'm short of coin so the best price I have found on a set of 40mm dells is $600 US, by the time post is factored in and the local taxes its getting up there. I have a set of 40mm Bings and are thinking of taking a punt on them just to see how they go on a race bike. Conventional wisdom suggests CV carbs are not as good a slide carbs. The D port heads I am going to use are 40/42 with an inlet stub for a 32 mm carb, 35 mm id on the port. Anton's site says there are 40/32 mm adaptors but I can't find them...:huh I welcome any thoughts on making Bings perform.
Oh I forgot to mention that the class of racing is " no Jap parts" I even persevere with Amals on my Norton... ( Winston would be proud of me)
You can get Amal Mk2s for £127 each from the UK. Smoothbore Amals are a bit pricey at £187 each. http://www.surreycycles.com/catalog...ucts_id=160&osCsid=fluaphernqpavci554au1so274
So no Japanese....that only leaves the rest of the world, time to think outside the box. My 34mm Blue Magnums are too small for a real big bike like yours, and I've only got one 36mm. Find another 36 and you've got 2, find a 38 and bore the 36 out ( I bored one of my 30's out to make 2 34's. The Blue Magnum is one of various carbs this guy designed, they are American and therefore don't tax the brain on tuning. How about a diaphragm carb? Tilotson or Walbro, you find big ones on outboards and jetskis, some people have used them on bikes. There was once a single Dellorto - like a twin choke side draught cut in half, I always wanted to give one of those a shot. Just trying to think outside the Bing, Dellorto, Mikuni box. Boxes can be restricting if you spend your life inside them, which Airhead types tend to do.
GuzziTony had Amals on his bike. He's replaced them with Mikinis recently... . I think you'd find the Bing CVs wouldn't give the 'snap' or immediate response you want.
I'm not so sure I need 'snap', as soon as I finish braking, turn in, you have to slowly get on the throttle. I'm keen to have a go and see. Sort of Airhead mythbusters.... I've proved that ATE brakes can be made to work well, why not Bings. My VW mate says I should mount a sidedraft dual 40mm Dell over the gear box.....
So bet you're reasonably comfortable that they didn't sell at auction then...Only one way to find out.
Hello Voltaire, the german R100GS and R100R are using the 40mm Bings on the small port heads with the M42 threads. So part number should be: 11121338361 But they're $55 each !!! No chance to get some fabricated? I could provide the dimensions if needed. Have a second look on your Bings. What's the diameter of the butterfly? The early 40mm Bings have 44mm butterflies, the later ones 42mm. And the spigotts should be built accordingly. Best regards, RG
Was hoping to part fund the Dells from the sale of the big valve heads and 40mm carbs but no interest. oh well.
From the sound of everything mentioned so far I would say you already have what would work best. 40mm Bings? Your 36mm Dell's will out perform them all through the rev range. I wouldn't listen to your VW mate! VW stuff rarely translates!!
Keep the big valve heads and use them. I'd prefer 38mm Dell Ortos. There has to be some good used ones out there.
Interest depends on price. At some price there is always interest. The big Bings have a lot of lag. It's a vacuum carb, you open the throttle but it doesn't really open (at the slide) until the vacuum builds. So it is always lagging behind your input. You can just roll it on easy but the Bing will be rolling it on easy sometime later. A big disadvantage. I rode a 90/6 with flatslide Mikunis (TMs, no pumps as I recall). It was like there was a steel rod connected to the power. You moved that throttle a fraction and the engine responded immediately.
I had them listed locally for $280.00 US. BMW stuff does not attract much interest here unless its give away prices. Saying that....that's why I have built a BMW race bike as cheap and solid. I'll probably just bung the 36's back on and up the main jet from 155. I tried to sell a 1971 VW Beetle project recently, $1100 US, plates on hold, all parts, not one call. Parted it out and doubled that, I just wanted the space for bike stuff
