Current single-carb recommendations

Johnfrmcal · 05-14-2009, 03:36 PM

Hello Harry,
I think I've read every word of every document on your website, great stuff!

I did notice one discrepancy though and I'd love to hear the most current recommendation.

On the "Kawasaki 650 models" page, under "Hammer Kit Intakes", it states:
"The 42 Keihin carb, used on all Group K Hammer kits, offers better overall fuel mixing and throttle response than any large throat single carb we have tested. This 42mm carb bolts directly onto the stock '91-'93 650 intake manifold where it works in concert with the small intake runners of the Group K modified '91-'93 650 manifold to provide throttle response and acceleration that no 44 Mikuni and few dual carb setups will match."

However, on the "Resto-Mod" page for the "F650 650SX" build, under "Carburetor and Inlet Options", it states:
"With hindsight being 20/20, the very best performing of these carb setups were a single 44 SBN Mikuni carb on an “opened up” stock inlet manifold, (or on an aftermarket inlet manifold)."

Also, on the '92-'97 750 models' page, it also references the 42 Keihin as being the hot ticket for a single carb setup (and better than most duals for that matter).

I have a '92 750SX that has the whole GroupK Hammer 92 kit on it, including the 42 Keihin and I love it. I'm building a 650 and a big-bore 750 at the moment, so I was wondering what your most current recommendation is for a single carb setup on either the 650 or 750 is, assuming a Hammer 92 type of build?

Group K · 05-15-2009, 12:12 PM

John,
We still like the 42 Keihin best on the Kaw reed 550, Kaw 650 & single carb 750s best .... But unfortunately they stopped making & importing those carbs 3 years ago. If you are lucky enough to find a good condition used one ... get it. Barring that, the next best choice for the K650 and K750 single carb setups is the SBN 44. The 650 struggles to have enough signal to make the 44 carburate ideally, but that just is the way it is. Signal with a 44SBN can be improved by running a stock 650 inlet manifold with an adaptor plate to accomidate the 44 carb. The small inlet runners of the stock manifold will help make the carb easier to tune. The much larger runners of most aftermarket single carb manifolds will weaken signal, and make tuning tougher (on lower rpm recrational setups).

We also like the true bored 38 Keihins that were stock on the single carb 750s, and later 650s, but they sometimes don't offer the range of pop-off adjustment to suit higher output setups.

Hope that helps,
Respectfully, Harry Klemm

Quote:

Originally Posted by Johnfrmcal

Hello Harry,
I think I've read every word of every document on your website, great stuff!

I did notice one discrepancy though and I'd love to hear the most current recommendation.

On the "Kawasaki 650 models" page, under "Hammer Kit Intakes", it states:
"The 42 Keihin carb, used on all Group K Hammer kits, offers better overall fuel mixing and throttle response than any large throat single carb we have tested. This 42mm carb bolts directly onto the stock '91-'93 650 intake manifold where it works in concert with the small intake runners of the Group K modified '91-'93 650 manifold to provide throttle response and acceleration that no 44 Mikuni and few dual carb setups will match."

However, on the "Resto-Mod" page for the "F650 650SX" build, under "Carburetor and Inlet Options", it states:
"With hindsight being 20/20, the very best performing of these carb setups were a single 44 SBN Mikuni carb on an “opened up” stock inlet manifold, (or on an aftermarket inlet manifold)."

Also, on the '92-'97 750 models' page, it also references the 42 Keihin as being the hot ticket for a single carb setup (and better than most duals for that matter).

I have a '92 750SX that has the whole GroupK Hammer 92 kit on it, including the 42 Keihin and I love it. I'm building a 650 and a big-bore 750 at the moment, so I was wondering what your most current recommendation is for a single carb setup on either the 650 or 750 is, assuming a Hammer 92 type of build?