Ditch the carbs

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prosnap

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EAAD1B92-4235-4397-96C6-5409DBE25EE5.jpeg 2F36B803-3686-4DF8-9BAA-E70C2CAEEEF0.jpeg 2F36B803-3686-4DF8-9BAA-E70C2CAEEEF0.jpeg B270E6D5-B4C2-4D93-ADE8-E25DE397F3D6.jpeg 8E56B769-1266-4D48-A257-0FA828A0A6A8.jpeg 7C87A830-49A9-4E43-81C1-C2AED5AF1B14.jpeg EAAD1B92-4235-4397-96C6-5409DBE25EE5.jpeg i got tired of dealing with all of the vmax carb issues,worn diaphragms,clogged passages and the pain in the ass removal and install. I made my own intake and installed twin Weber knock offs. I have had them on for over three years now. My bike always starts right up and no more carb issues. And since the carbs have accelerator pumps no choke needed.
 

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Are there orings between the spacers/plates to seal? I think it's a great idea and good work so far. I think an improvement could still be done with a better transition from the carb to the intake but still a good looking setup.
 
Pretty-stout! Looks like something that could be 3-D printed.

For some reason it reminds me of an overhead intake, flathead exhaust system, sometimes used pre-WW II in engines.

Seems like using some foam and epoxy you could easily blend the transition from the carbs to the VBoost, to eliminate the extra space. That would be an interesting experiment, to make a second manifold, do the foam/epoxy, and see what the dyno says. I bet it would improve airflow everywhere in the rev band.

I bet a skilled 3-D printer person could make that transition too.

Your 3-year 'trial' is a documented 'proof-of-concept.'

The comments about Chinese-sourced Weber carburetor copies not-lasting, 3 years is a decent timeframe of use, maybe this is a better supplier than something-else from another factory.
 
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Are there orings between the spacers/plates to seal? I think it's a great idea and good work so far. I think an improvement could still be done with a better transition from the carb to the intake but still a good looking setup.
The transition is very thin. that way the factory look can be maintained allowing to close the lid.mounted.jpg front.jpg rear.jpg
 
For sure nice and I am sure you'd have plenty of people who would be looking for a kit to replace heavily worn stock carbs. Would be great to get some before/after testing as well
 

$93 apiece, free shipping! Now, what would it cost for the non-machine shop person to acquire the manifolds?

Price at Ron Ayres Motorsports currently for a single carburetor diaphragm:
. Diaphragm Assy

1FK-14940-00-00 1FK-14940-09-00

$117.52
https://www.yamahapartshouse.com/oemparts/a/yam/50045c0ef8700209bc7942f3/carburetor

I'd be interested to see the throttle hook-up, is it possible to use the OEM two-cable system? How do the two throttles for the two, two-bbl bodies attach?

Thinking more about the venturis for the carb mounts, since everything is 'stacked,' couldn't you print an insert which would just sit captive between the two carburetor mounting plates, providing a smoother path for the airflow? Kind of an offset 'funnel?' You might be able to tune that, smaller path for higher velocities and more torque, larger path for a high in the rev-range power bias. A wild idea: a pneumatically-operated bladder which changes the diameter to suit your intended use! Since the volume of the area is small, it should be quick to pump it up/make-smaller the venturis for a torque bias, and also the opposite: let air out to enlarge the passages, for a high horsepower/high rev band use, like at the strip.

A question about the 'RamAir' foam air filter elements: are they just 'socks,' which slip-over the carburetor velocity stacks? How well-sealed are they to the velocity stacks? They appear to be running dry not oiled like a SS mesh and cotton gauze K&N. How-dense is the filtering material? I expect that something like that is a frequently-replaced item, if you want effective filtering. Is the overall shape of the filter like a can of Spam, with a couple smaller holes cut-into the bottom of the filter, so you just stretch it over the velocity stacks, and rely upon the elasticity of the foam material to provide a seal?

I have to say, this is probably one of the biggest new parts introduced into our VMax world since the Ignitech provided us with an alternative to the OEM CDI ignition box. Now for the litmus test: a dyno run, on a stock Mikuni-equipped bike, in stock configuration, against this system. Follow that with an extended road test, perhaps even a strip appearance. There are a few members on here who have thrashed their bikes at the strip, and who seem to be good at it. Remembering our departed friend Joe Alorio, he once shared with me his stone-stock bike's dragstrip trip, when his bike was pretty-new, and I believe he was in possession of a 10.8 second, ~125 mph timing slip. See post #5: https://www.vmaxforum.net/threads/thanks-rusty-for-the-great-job-of-polishing.29647/#post-319215

Running the same bike on the same dyno, with the replacement two, two-bbl. switched out with the stock OEM induction set is the argument-settler. First, the OEM carbs, second, the Weber twin two-bbl setup.
 
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$93 apiece, free shipping! Now, what would it cost for the non-machine shop person to acquire the manifolds?

Price at Ron Ayres Motorsports currently for a single carburetor diaphragm:
. Diaphragm Assy

1FK-14940-00-00 1FK-14940-09-00

$117.52
https://www.yamahapartshouse.com/oemparts/a/yam/50045c0ef8700209bc7942f3/carburetor

I'd be interested to see the throttle hook-up, is it possible to use the OEM two-cable system? How do the two throttles for the two, two-bbl bodies attach?

Thinking more about the venturis for the carb mounts, since everything is 'stacked,' couldn't you print an insert which would just sit captive between the two carburetor mounting plates, providing a smoother path for the airflow? Kind of an offset 'funnel?' You might be able to tune that, smaller path for higher velocities and more torque, larger path for a high in the rev-range power bias. A wild idea: a pneumatically-operated bladder which changes the diameter to suit your intended use! Since the volume of the area is small, it should be quick to pump it up/make-smaller the venturis for a torque bias, and also the opposite: let air out to enlarge the passages, for a high horsepower/high rev band use, like at the strip.

A question about the 'RamAir' foam air filter elements: are they just 'socks,' which slip-over the carburetor velocity stacks? How well-sealed are they to the velocity stacks? They appear to be running dry not oiled like a SS mesh and cotton gauze K&N. How-dense is the filtering material? I expect that something like that is a frequently-replaced item, if you want effective filtering. Is the overall shape of the filter like a can of Spam, with a couple smaller holes cut-into the bottom of the filter, so you just stretch it over the velocity stacks, and rely upon the elasticity of the foam material to provide a seal?

I have to say, this is probably one of the biggest new parts introduced into our VMax world since the Ignitech provided us with an alternative to the OEM CDI ignition box.
 
The filters are open pore foam that stretch around the horns. the whole sock becomes the filter because the sock does not slide down to the top of the trumpet.
i make the intake as needed by anyone wanting one. but i would only sell to someone that is capable tuning the carbs on there own. i have a manual on how to assemble the carbs to the intake and mounting the parts on it to make it ready to drop in the bike. all of the parts that i supply with the manifold are complete for the install. as far as the airflow path of the intake, this is the shortest path of airflow possible without any type of restrictions. as far as the throttle cable, you are only using the pull cable,the return cable is removed. Both carburetors have there own return springs which is plenty of strength for the throttle return. when you get your crbs you must follow the cleaning procedure that i posted. Anyone wanting to order a manifold should read the install manual that i put together. the install manual includes the drill sizes for the jets that i am currently using. i did not refine my tuning because the bike ran like a raped ape. i was satisfied , i accomplished what i wanted to do and that was getting away from those shitty factory carbs. i am sure an enthusiast would take the tuning to another level but right now i feel that this setup gets the maximum from the engine. mission accomplished.
 
Thats funny, a single diaphragm cost more than 1 carburetor. now you can see why i created the manifold.
 
i only sold one of my manifold kits to a gentleman that is a vmax enthusiast. he has a vmax trike and a vmax four wheeler. his own bike is a upgraded vmax big bore 1500. at the time he was running some type of flat sides carbs which alone were about 2200 bucks. anyway , He gained 21 more horsepower over what he was getting with the flat sides. That might not seem a lot but for a motorcycle that's huge. i was going to sell a complete kit with carbs but decided against it because you can never satisfy everyone as far as making a perfectly tuned system. i didn't even want to try. i thought that there were other people out there like me dealing with the factory garbage and wanted a cheaper system and get back to riding rather than tearing things apart and blasting with air.
 
View attachment 69352 View attachment 69348 View attachment 69348 View attachment 69349 View attachment 69350 View attachment 69351 View attachment 69352 i got tired of dealing with all of the vmax carb issues,worn diaphragms,clogged passages and the pain in the ass removal and install. I made my own intake and installed twin Weber knock offs. I have had them on for over three years now. My bike always starts right up and no more carb issues. And since the carbs have accelerator pumps no choke needed.


That is very impressive!!!!!
 
i only sold one of my manifold kits to a gentleman that is a vmax enthusiast. he has a vmax trike and a vmax four wheeler. his own bike is a upgraded vmax big bore 1500. at the time he was running some type of flat sides carbs which alone were about 2200 bucks. anyway , He gained 21 more horsepower over what he was getting with the flat sides. That might not seem a lot but for a motorcycle that's huge. i was going to sell a complete kit with carbs but decided against it because you can never satisfy everyone as far as making a perfectly tuned system. i didn't even want to try. i thought that there were other people out there like me dealing with the factory garbage and wanted a cheaper system and get back to riding rather than tearing things apart and blasting with air.

That had to be putting him into stock Hyabusa territory!
 
Great stuff.
I was looking thru the PDF about cleaning those webers and see the guy had a link to tuning the same carbs. The link didn't work for me.
Do you know where to find that pdf on tuning?
 
Great stuff.
I was looking thru the PDF about cleaning those webers and see the guy had a link to tuning the same carbs. The link didn't work for me.
Do you know where to find that pdf on tuning?
i would just do a google search on idf weber or delardo tuning. alot of volkswagons use dual webers , you might want to take a look at some of those forums. like i said in my manual, i didnt get carried away about the tuning and actually the carburators are really not complicated at all. in fact they are the most simplest carbs to tune.
 

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