Motorcycle intake adapter

[Commander_Chaos]

I realize this is a nothing job for a real machinist but it was a big deal for me. A friend of mine wanted to put an English carburetor onto an Italian motorcycle, so metric vs imperial.

I was proud of the fact that I hit the hole spacing within a couple of thou and got the 27mm bore right. He needed the carb to be on a 12 degree angle from the head and the angle of the bore to split the difference. I got a really nice finish right off the mill with no polishing.

[chipmaker4130]

Way to go! No excuses now!

[A.K. Boomer]

An English carburetor on and Italian Motorcycle --- total sacrilege...

Italy not only produces some of the best carbs in the world - but engines too so even in reverse would have been a sin...

BUT --------- very nice job in the melding of the two - no matter how inappropriate... im sure the over all appearance will look like the seed of a crossbow wedding...

[Jim Stewart]

An English carburetor on and Italian Motorcycle --- total sacrilege...

Italy not only produces some of the best carbs in the world - but engines too so even in reverse would have been a sin...

BUT --------- very nice job in the melding of the two - no matter how inappropriate... im sure the over all appearance will look like the seed of a crossbow wedding...

Yeah! Geez - Amal vs. Dellorto. Not to mention Weber for the cars.

I've had all of them. Must say, I've never, never seen such a wonderful carb as the Weber 40DCOE. Everything is adjustable with the carb mounted. Jets, sure but even the venturis can be changed without tools. Amazing devices.

Of course, with so many adjustments, there are many, many ways to get them screwed up.

-js

EDIT: Although I do like SU carbs. (Many people think I'm nuts.) They're very adjustable if you know what you're doing. There are very few of us left...

[A.K. Boomer]

Yeah! Geez - Amal vs. Dellorto. Not to mention Weber for the cars.

I've had all of them. Must say, I've never, never seen such a wonderful carb as the Weber 40DCOE. Everything is adjustable with the carb mounted. Jets, sure but even the venturis can be changed without tools. Amazing devices.

Of course, with so many adjustments, there are many, many ways to get them screwed up.

-js

Very cool - yes the Weber's were fluidic art, im going to have to check out the venturi design your talking about because that's a new one to me just incredible the lengths they took it too...

[Jim Stewart]

Very cool - yes the Weber's were fluidic art, im going to have to check out the venturi design your talking about because that's a new one to me just incredible the lengths they took it too...

It's amazing in its simplicity. Simply remove the air cleaner, press on a clip and slide the venturi out with your fingers. Then you go to your expensive stash of Weber parts and choose one that's larger if you're going for peak HP or smaller if you want better throttle response. Can't remember how many venturi sizes were available, I could only afford one.

-js

[A.K. Boomer]

It's amazing in its simplicity. Simply remove the air cleaner, press on a clip and slide the venturi out with your fingers. Then you go to your expensive stash of Weber parts and choose one that's larger if you're going for peak HP or smaller if you want better throttle response. Can't remember how many venturi sizes were available, I could only afford one.

-js

It sounds good for it's time - but I think the vacuum slide carbs did that kinda automatically no? they seem to be a great update on the old school carbs in allot of ways and all kinds of manipulative tuning can be done... maybe in a way if the brits would have perfected their old strombergs or NSU's it would have been a good thing but I remember them things as being very crude and hard to tune...

I have to put credits to fuel injection --- damn --- i don't even need to worry about fuel mixture anymore - so much so that i forget what a pita it used to be...

[Jim Stewart]

Oh, no argument there from me. FI has changed everything - but we're talking about fifty years ago. Or, in the case of SUs, ninety years or so.

-js

[Commander_Chaos]

Yeah! Geez - Amal vs. Dellorto. Not to mention Weber for the cars.

I've had all of them. Must say, I've never, never seen such a wonderful carb as the Weber 40DCOE. Everything is adjustable with the carb mounted. Jets, sure but even the venturis can be changed without tools. Amazing devices.

Of course, with so many adjustments, there are many, many ways to get them screwed up.

-js

EDIT: Although I do like SU carbs. (Many people think I'm nuts.) They're very adjustable if you know what you're doing. There are very few of us left...

The guy I made it for has a shop. There was a 350 Ducati he wanted to get rid of but it needed a carb. He had plenty of Amals, so...

I have SUs on my MG. I hear they're a pain to set up but keeping them in adjustment hasn't been a problem for me. John Twist's videos were all I needed.

[J Tiers]

The adapter looks very good. Perfect use of a shop.

...........................................

EDIT: Although I do like SU carbs. (Many people think I'm nuts.) They're very adjustable if you know what you're doing. There are very few of us left...

I had dual SU's on a car decades ago. Long after I got rid of it, I found out that it was one that was vented in the body, and the problem was that the caps for the dampers were also vented. It was supposed to be one OR the other. A couple dabs of epoxy would have fixed everything

I wish I had known that long ago. The carb wasn't that bad, even if it was British, but with two vents, it sucked all the ATF out of the damper very soon, and naturally was squirreley after that, with the two unbalanced and responding wrong. I probably had it adjusted fine.

As a carb design, it kinda made a lot of sense.

But I sure hated them at the time. I just had no idea that I should have closed the vents in the caps.

[plunger]

How difficult was the transition of the bore from the bottom to the top . The angle must have complicated things.

[Commander_Chaos]

How difficult was the transition of the bore from the bottom to the top . The angle must have complicated things.

There was some head scratching but the solution I came up with involved a cheap angle vise for a drill press. The first operation was to bore the 27mm hole straight through the piece and I took 6 degrees off of each face later. I used that setup for the bolt holes, too.

I should probably make a sine plate.

[CalM]

Hmm .... Dellorto or Amal? Just no BING! ;-)

[dneufell]

Jim Stewart .....Yes very adjustable. In the 70's i put a double barrel Dellorto carb single manifold on a 1963 Harley 900 Sportster. Crazy jets , accelerator pump and emulsion tube changes to get it running well

[BCRider]

CC, you did just fine. I'd be proud as a peacock if that came out of my own shop. Give yerself a pat on the back!