Dual Carb System

[DuctTapedGoat]

Hey, I'm considering taking a dual brake setup and combining it with throttle setups. I want to do a dual carb! I know I'm looking at some VERY SERIOUS tuning, but this is something I want to do just to prove it can be done.

I know boost bottles have been talked about a lot recently, and after some deliberation I've decided that the best way in my own personal opinion to get the concept itself working in all peak efficiancy, a second carb is the solution.

Anyone have any advice, tips, opinions, questions?

 

[gothicguy64]

hi

i believe 16 to 19 mm is the go for 1

so i guess a 9 mm carby is what ull need

an a 9 mm is rc car size

brad
syd

 

[HeadSmess]

um, yes, it will woooork...but why? i see absolutely no benefit on an engine like this...

if it was fitted with a 32mm keihin then, yes, maybe two 18mms side by side could be better, but...

if two carbs was better, it would be done on a constant basis! theres only one bike that did it and thats the honda XR! and it was silly! and it was returned to normal in later models!

maybe a twin barrell style thing...but where to find one?

oh well. your money, your bling. not my prob

 

[DuctTapedGoat]

Lol, I'm not worrying about what it'll cost. I just want something fun to mess around with. Twin carbys are always tough to tune, I just haven't ever heard of it on a two stroke. Not that it NEEDS to be done, I'm just saying it'd be fun. And it ties in with a HUGE HUGE HUGE mod which I'm posting in product dev section.

I've been thinking about doing it two ways, one by way of a T fitting and have one on the left one on the right, and the other way would be inline, just using a coupler.

I've seen working boost bottles, and they weren't solidstate bottles, they were accordion style bottles on the end of the hose which actually breathed from pressure, not relying on a useless vacuum. That's how to emulate the twin barrel.

This would just be a way to increase air intake, increase fuel intake and at the same time take advantage of a ported exhaust.

There is benefits, and they will be running individually. Plus it's one of the parts to a grander scale of mod, which is in product development section.
http://motoredbikes.com/showthread.php?t=31498

 

[wheelbender6]

If you want two carbs; do it. You see plenty of things on the motors at car shows that are not practical but look awesome.
Be advised that you will lose some bottom end power with a pair of jugs. You may be able to make up that loss with a reed valve.
There is a post somewhere showing a China motor with a home made dual carb setup. I'll try to find it.

 

[motorpsycho]

I would do it just for the looks, because 2 carbs look cooler than one.
You could use 2 n.t. carbs jetted down very lean.
You would have to build a Y intake manifold and make a 1 into 2 throttle cable.
It would not be that difficult to make all the parts, the jetting would be the hard part.

 

[DuctTapedGoat]

I'm not sure which would be better - to run dual throttle, or to do independent throttles.

Jetting is what it all comes down to here, unlike a 4stroke with dual carb, there's not any timing issues to worry about, only jetting. They'd have to jetted really lean! But, they're cheap enough to where getting them from SBP wouldn't be a problem at all - even messing around with independent throttles and different sized jets on each carb.

This wouldn't serve much great a purpose, but I think it'd be fun, especially on a long ride having a lot finer tuning on the go with no tools. As well, I can just turn each carb on or off at will, so it's not like I'm stuck with two carbs at full throt.

Definitely let us know if you find that link!

 

[a/c man]

Here's a couple of pics a forum member posted with his dual carbs.
Clay is one of the best 2 stroke bike guys out there.
I believe he goes by foureasy on the other forum.

http://www.motoredbikes.com/showthread.php?t=22424

Scroll down the page to post #4

TIM

 

[kaino(Aus)]

Holy s##t twin carbies. thats link is sweet. im makin one tomorrow.

 

[rustycase]

deuce

It may not be too bad an idea, dtg...
Try progressive linkage.
One small tube will get you bottom end, and the pair wide open will give you superior top end.
...just might work!
I looked at Clay's pics... he sold the first setup and went with longer runners for the second version. I like his pipe running under the frame...

Good luck with carbs,
rc