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Re: Hi-Carb diet

Ben Barkow dr.ben@xxxxxxxxx <mailto:dr.ben@xxxxxxxxx>  wrote:

[In addition to some thought-provoking comments on front suspension]

>Few hobbyist biker activities are more challenging, rewarding, frustrating,
and beneficial that carb switcheroos. CRAZY. I've done it twice on Airheads
with never-before-attempted carbs.... crazy. Carbs are very very subtle and
have maybe 6-8 variables which you must tamper with to get passable
performance. And not cheap.

I'm well aware of the 6-8 variables, which is exactly why I'm looking for a
kit. Like Tom, I don't have time these days to do the experimentation to get
it right. But there are others who live for it, and I'd like to be able to
stand on their shoulders. Presumably, someone in Europe has got the recipe
figured out. If the stuff came in a box and all I had to do was bolt it on,
I'd be all over it.

On our Husqvarna dirt bikes back in the '70s, my father and I replaced 5 Bings
and one Amal with Mikunis, and later Lectrons, with GREAT success. It made ALL
the difference turning those bikes from recalcitrant, infuriating,
plug-fouling beasts into utterly reliable, 1st-kick starters.

I also replaced the Bings on my R60/6 with a pair of 26mm DellOrtos, with
great success; but in those days I was bachelor working in a machine shop. I
had to fab up some aluminum sleeves in order to mount the carbs to the intake
spigots, and it took me quite a while to get a truly satisfactory connection
to the airbox (the answer, it turned out, was that R80 tubes worked
perfectly!). I had to make some extended throttle cable adjuster screws, but
the stock cables worked fine, and an R90S choke lever/cable assembly fit

And you know what? I never changed a jet. Once I got the DellOrtos physically
installed I picked up 4mpg, the bike started better, ran great, and for
another 30k miles never went out of adjustment. The Bings had required
adjustment every few thousand miles (or less!)--just like oilhead throttle
bodies do.

I did some shopping at the local dirt bike shop a couple months back, and
found I can indeed buy a pair of 41mm Mikunis for about the same price as a
set of new Bing throttle bodies. I also made contact with Lectron, but never
followed up to get a price.

But that does not begin to address the issues of getting the carbs to mate
mechanically, throttle cables, ignition mysteries, and last but not least
proper jetting. And since (theoretically) I don't actually "need" to replace
both entire throttle bodies, $60 for replacement parts from Bing was the

THIS time.

John D