• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

Why so many carbs?

  • Thread starter Thread starter t3rmin
  • Start date Start date
Wow. Everything anyone could ever want to know about carbs is in this one thread! :shock:
 
Tnutz said:
No parts to wear out like a carb, no synching...maybe a clogged injector someday....but thats about it....:-D technology! once you go efi you will never go back.
Click to expand...

Agreed...I love EFI. As the cost has been going down, I see more and more drag cars going to EFI. Efficient, works great and you fine tune it with a lap top....

If there was an easy, low cost way to put a EFI system on my GS drag bike I would...heck, I'd consider it for my street GSes if it didn't cost more than the bike was worth....

I'm actually toying with the idea of adding EFI to my single cylinder, 500 BSA....just to do it.:-D

Later,
Bob T.
 
dpep said:
New FI systems work better than our 25 year old carbs. I am curious how well those FI systems will be working 25 years from now. Will it be possible to repair them and if they can't be fixed will replacements be available? It will be 25 year old electronics technology by then. The carbs on our GSs will still be working like they do now and we will be able to service them the same as we do now.

I am not against progress. But I am always a little cautious about developments that take a part of my bikes functioning away from me and give it to a black box.
Click to expand...


Good point. You'll probably have to stick a 50 year old carb on an EFI bike 25 years from now!
 
This is my take on the real reason single card over multi. The ole saying if it aint broke don’t fix it! They were putting these carbs on these bikes for years. Why reinvent the wheel? They create great upper end power and at that time fuel economy wasn’t an issue. That’s probably what riders were looking for in a bike at that time. It was a durable design that worked. A motorcycle company wasn’t going to go out on a limb to design something different and take a chance on it flopping. Especially during the GS’s life span where motorcycle competition was fierce. It’s also easier to be able to use the same carb and intake boot for a different bike that doesn’t have as much space where they might have to redesign a special intake for each model. Easier to just make a different air box. Just my opinion.

Oh and as far as intake on cars go (or bikes for that matter) the different size runner on an intake should be determined by what heads & cam you run. If you have large valve, large runners (on the head) and a cam that starts making power around 3k to 7k+ then you want an intake that is a tunnel ram or a single plane. Something that is not going to restrict flow. On the other hand if you want to make torque and your power band is in more of range of idle to 5k you want shorter/smaller runners to create a denser charge. Of coarse there are other factors like if it’s a straight or V or the size of the crank to determine how high a motor can rev but that’s to deep a subject to get into right now.
 
The decision to put multi-carbs on our bikes was an easy one. At the state of tune these GS engines have, a single carb would work horribly. It could be designed to make good power but it would idle like a pop corn machine and would not be smooth at cruse speeds, get bad gas mileage, and would not pass emission tests of the day. Sounds like a hopped muscle car doesn't it. The problem is big cams create a situation where vacuum and intake pulses from one cylinder disturb the others and a accurate fuel mixture becomes impossible. With individual throats they are isolated from each other and each cylinder has its own mixture screw for accurate adjustment. Single carbs are fine for a mildly tuned car engine. I have tuned big V8's engines with multi weber carbs with big cams and they run fantastic, idle like glass and are as smooth as can be. Dan
 
You must log in or register to reply here.
Back
Top