Weber 45 DCOE vs R1 40mm bike carbs

Flow testing Weber 45 DCOE with 36mm hhoke and 4.5 aux venturi vs R1 40mm Keihin bike carbs both at WOT
R1 carbs flow a little more air but when 37mm chokes or larger are fitted to the 45's they flow more than R1 40mm bike carbs, back to back testing

[@vasiliansotirov6976]

Guys, i think that's vacuum. So r1 carbs show less vacuum, therefore better airflow.

[@johnnykeller7648]

Look, if you're measuring flow rates at WTO, the 45's are OBVIOUSLY going to be better than the 40's. The only thing that surprised me was the vacuum...which was comparitively close but the DCOE's still edged it out.
I opted to put 45's on my 4AG, simply due to increased serviceability, and parts availability.
I had the options of Solex, Mikuni, or Deloreto's and opted for the Weber's due to parts availability (they were bought out by Deloreto sometime back in the 90's and Deloreto continues to actively produce rebuild kits for the full DCOE linup as well as jets) Kehin bought the rights to Mikuni (as well as all pre-existing IP's/patents) and has essentially done nothing with it, but sit on it; they're not reproducing parts or rebuild kit's at current date to my knowledge.
The choice between the two became pretty much a no-brainer...Weber's.

[@zardozfromoz]

Can you tell me what the unit of flow on the meter is?

[@Stormcloakvictory]

I have no Idea what units the device uses and it actually actually measures (I'm guessing airflow)But here's some of the data I roughly saw:Weber had -17.22/-17.49 on the device and 21.6/21.8 cm on the tape measure.R1 carbs had -17.18/-17.29 on the device and 21.6/21.9 cm on the tape measure.
I guess the weber is better?

[@iava1981]

The 45's have 36 mm chokes, the r1 Carb have a 40mm choke on full throttle, is not the same, you must do your experiment Under the same condition. You are trying to say that the r1 have the same velocity than the 45 with less diameter. Do It well.

[@benoloksa3535]

Thanks

[@danielsilvabrum7583]

What is the best?

[@cdgmemphis]

I'm surprised at the results. Think I'll go back to 45s!

[@crisoforoc3752]

Que carburador recomendarías para 2.3 L 16v. mercedes Benz.? ke-Jetronic original sistem is broken an no more work. this engine work hig rpm. max velocity 240kmh 6300rpm, what is the cfm necesary suport carburetor., an what is the indicated carburetor for this car , any carburetor car or bike?. Thanks. and sorry for mi inglish im not speak good and write. im. from mexico. Saludos. And congratulations you are cintific skills and profesionally test.

[@huehueteotl03]

Prácticamente tienen la misma lectura de vacío 17 pulgadas de agua, lo que supone que los atraviesa el mismo flujo de aire y en consecuencia producirían la misma potencia... Por otro lado, yo usaría los carburadores de moto de 40mm porque serían más "responsivos" al pedal.

[@mtzmiguel167]

Hola, estoy buscando poner unos carbuladores para mi Datsun 1800 pero la verdad que no tengo idea de cuales, claro de moto. Algunos que me puedas recomendar te agradeceré mucho. Posdata: que buena moto te armaste.

[@huehueteotl03]

@@mtzmiguel167 Tienes que conseguir carburadores que vengan de una moto que tengan una cilindrada de 900 a 1000cc, los mismos vienen equipados con espreas de marcha mínima y de carga, tendrás que buscar las espreas de marcha mínima correctas que ajusten el funcionamiento de tu motor en bajas rpm y esto se logra normalmente aumentando el calibre de dichas espreas, por ejemplo si tus carburadores traen espreas de baja de calibre 60 busca colocar unas de calibre 70 y hacer pruebas en marcha mínima esto es que: la misma sea estable y sin variaciones de velocidad, esto es así porque los carburadores en baja esperan alimentar un motor de 900cc y no uno de1800cc. las espreas de carga normalmente no se tocan ya que el flujo de aire que mueve un motor 900cc @10000 rpm es el MISMO que maneja un motor 1800 @ 5000 rpm. Tienes que fabricar un múltiple de admisión y colocar en el mismo la toma de vacío para el booster de tu bomba de freno. En fin la adaptación no es solo quitar y poner, tienes que ir ajustando la gasolina y el aire según te pida tu motor.

[@mtzmiguel167]

@@huehueteotl03 buenísimo, si estoy por hacer todo el cambio, y me lo explicas muy bien. Muchas gracias por tu tiempo y amable respuesta. Ahí voy a subir como queda. Ya baje incluso el motor espero quede bien. Saludos

[@ulisesavila2879]

y absurdamente mas baratos

[@jram0001]

45's are the best,

[@stuartjakl]

If Webers are so great then why weren’t they original equipment on motorcycles?
The fact is that those motorcycle carbs perform much better at a wider range of altitudes and throttle settings than the Weber can. I’ll take the motorcycle carbs

[@Grooty79]

So the test reveals that a 36 mm choke with a 45mm throttle butterfly can flow very similar to a 40mm bike Carby, I still would rather the 45mm Weber, the vacume signal at the main jet needs to be measured to establish the stronger signal and then ide go with the stronger of the 2 , ide think the Weber would have the stronger signal

[@carlosjauridez4438]

I don't know what tried to say, Who win the weber 45?

[@noralizanoraliza1130]

000

[@carlosjauridez4438]

Ok

[@jackgtir1]

so what was the results ? don't really follow it myself sorry