from four to two

LLC, as far as using the Holley as a sidedraft, it won't work because of the float bowls. Yeah, a holley on a straight six is to the side of the engine, but it's still a downdraft, the intake is pointed up. MC carbs are sidedraft, the intake is in the horizontal plane with floatbowl oriented for proper operation. I don't know of any four barrel carb that is designed for sidedraft operation. What about SU carbs? They make some pretty honkin' sidedrafts!

oops sorry, forgot they were already mentioned.

OK, forget the Holley. How about a nice Weber? They make sidedraft carbs. You KNOW a Weber would look trick on any bike! Scroll to the bottom of the link for examples:

Weber Direct

larrycavan wrote:

Interesting tests you did..... We should have a discussion on that in a new thread. There are some things I'd like to point out but I don't want to hijack this guys thread...

That would be great, but I'm betting very time consuming. I just barely started tinkering with it and ended up with pages and pages.

55fbomb wrote:

the outside cylinders starve with a single carb log. why not use a twin carb log?

The far cylinders will not starve. Like i said. Auto manufactures have been using loy type intake on four and six cylinders for many years. Engines ranging from 1.0L to 5.2.L This will be no different.

seanbarney41 wrote:

LLC, as far as using the Holley as a sidedraft, it won't work because of the float bowls. Yeah, a holley on a straight six is to the side of the engine, but it's still a downdraft, the intake is pointed up. MC carbs are sidedraft, the intake is in the horizontal plane with floatbowl oriented for proper operation. I don't know of any four barrel carb that is designed for sidedraft operation. What about SU carbs? They make some pretty honkin' sidedrafts!

oops sorry, forgot they were already mentioned.

Simple fact is A downdraft carb would work, All I would have to do is make an up turn in the intake manifold. Like i said before Im not going to use a holley never did and never will. That wasnt my idea. Only reason why, is it would look god awful with a 500CFM 4 barrel which sticking out the side of my bike. That would look silly and ridiculous.

Not to mention even using a 2 barrel holley at 350 CFM is stupid, the stock 1.0L doesnt require such a large amount of air. so I would have to use TINY jets which would pretty much defeat the purpose of using such a carb, and render it useless.

650ed wrote:

OK, forget the Holley. How about a nice Weber? They make sidedraft carbs. You KNOW a Weber would look trick on any bike! Scroll to the bottom of the link for examples:

Weber Direct

I did consider using a weber, there great carbs, theyre cheap and readily available parts. But I dont want anything that big.

I have fitment issues due to the style frame and the mid controls. I have to keep it as small as possible otherwise itll be hitting my knee.

Im going to run either a BS34 Mikuni or a Bendix/Zenith.
I have six BS34's laying around im gonna try it with one of those first, see how it does. If i end up needing a larger carb ill check out the bendix.

Ok LLC, I get ya now. I didn't really think you wanted to run a Holley. I was just shootin' the sh!+. Too bad the webers won't fit, I saw a stripped down Goldwing this summer that was runnin' downdraft Webers and it looked killer

seanbarney41 wrote:

Ok LLC, I get ya now. I didn't really think you wanted to run a Holley. I was just shootin' the sh!+. Too bad the webers won't fit, I saw a stripped down Goldwing this summer that was runnin' downdraft Webers and it looked killer

Yah dont get me wrong I wish I could. But I dont want to slam my knee into the carb every time in need to hit the brakes quick ya know?

Those dual webers and badass. haha

Maybe the nest bike I do I might do something with a weber. The next one i build will have a stretched frame so the mid controls wont be so "mid" anymore. I might be able to fit something a little bigger then.

I have talked to a lot of guys that used logs on cb750s and heard pretty much nothing good except they are different. good luck.

55fbomb wrote:

I have talked to a lot of guys that used logs on cb750s and heard pretty much nothing good except they are different. good luck.

I dont understand why everyone is having hard time with this. Almost every auto manufacturer for the last 20 or more years has been creating vehicles with 4 and 6 cylinder engines with log style intakes. from carbs to fuel injection. this is not a new concept nor difficult. In fact itll be much easier to accomplish due to a motorcycle engine not needing the kind of atomization a larger engine would require. Its pretty cut and dry folks.

LLC wrote:

55fbomb wrote:

I have talked to a lot of guys that used logs on cb750s and heard pretty much nothing good except they are different. good luck.

I dont understand why everyone is having hard time with this. Almost every auto manufacturer for the last 20 or more years has been creating vehicles with 4 and 6 cylinder engines with log style intakes. from carbs to fuel injection. this is not a new concept nor difficult. In fact itll be much easier to accomplish due to a motorcycle engine not needing the kind of atomization a larger engine would require. Its pretty cut and dry folks.

Post some photos of what you're working with for space restrictions....

LLC wrote:
4 and 6 cylinder engines with log style intakes. from carbs to fuel injection. [/quote]

I've only seen "log-type" intakes for multi point FI. I'm not saying your project won't work, but any throttle-body FI or carb usually has runners (ideally) close to equal length.