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Bike carbs
Stuart_B - 2/1/08 at 02:15 PM

hi, i have just got a set of cbr600fx carbs to put on my 1.6 pinto engine, i has wondering what will i have to do??

thanks

Stuart


takumi - 2/1/08 at 02:24 PM

you will need a manifold to mount them
Bogg Bros do nice ones in alloy.. but expect to pay around £170

You often see them on ebay in stainless steel for upto £140..

You can alwys DIY cut a inlet manifold flange, and weld on some tube stubs, hey presto..


takumi - 2/1/08 at 02:26 PM

http://www.boggbros.co.uk/gallery.html


zilspeed - 2/1/08 at 02:31 PM

This is the very issue I have been thinking about today. Being your classic time rich. cash poor person, I will be looking to make one.

I have some Yamaha FZ6 throttle bodies to go onto my 1.8 zetec. This is what I have come up with to mate the above.

This is based on the bore centres of the throttle bodies and the bore centres of the zetec being different but sharing the same centerline. On this drawing, I have allowed a stright part to allow for mounting the throttles using silicon tube.

[Edited on 2/1/08 by zilspeed] Rescued attachment Manifold.JPG
Rescued attachment Manifold.JPG


takumi - 2/1/08 at 02:52 PM

You have the option of respacing the carbs - and having straight tubes..

Not as difficult as you would have thought, worth considering.


David Jenkins - 2/1/08 at 02:59 PM

If you look on my website (link below) and click on 'bike carburettors' you'll find some useful info (I hope it's useful, anyway!).

David


Pdlewis - 2/1/08 at 03:07 PM

if you look at david jenkins post in the engine section this topic is covered in alot of detail


jacko - 2/1/08 at 04:38 PM

Hi i made my manifold have a look in my photo archives it will help you
Jacko
ps do a serch under my name lots of info in there


Stuart_B - 2/1/08 at 04:46 PM

hi, i was thicking of make mine own manifold out of steel, and have 4 tubes bent and then go into the rubbers own the carbs, like zilspeed picture above, but i do not know what all the pipes go and do, any ideas?

David Jenkins very good info on you site, have you got a infomation about balncing the carbs, as well of what does all the pipes do, and i need to keep and don't?

Thanks

Stuart


UncleFista - 2/1/08 at 05:12 PM

We made ours from 5-6mm plate for the flange and 1mm sheet rolled into tubes.

Drilled the jets out to 1.65mm (I think) and Bob's yer uncle, fired first time and runs great.

No carb balancing or mixture messing yet, it runs too well to start messing with it

Zetec 1.8 on CBR600 carbs;

view from top
view from top


view from front
view from front


Stuart_B - 2/1/08 at 05:19 PM

hi,
what about the throtle cables as there are two, are they push and pull how does this work??

And what pipes do what??

thanks

Stuart


UncleFista - 2/1/08 at 05:45 PM

We just used 1 cable and used a spring instead of the "pull to close" one.

As for the pipes, apart from the fuel inlet, they all usually go to the airbox, but as we don't have an airbox, I've justy left 'em open the the atmosphere.

I have a workshop manual for the CBR600 carbs in PDF format, if you drop me a mail I'll send you a copy if you like

locostATblueyonder.co.uk

BTW the other cable you can see is the choke


[Edited on 2/1/08 by UncleFista]


Stuart_B - 2/1/08 at 06:49 PM

did you use the cbr cable or a diiffernt cable?

thank you

stuart


UncleFista - 2/1/08 at 06:54 PM

We bought a cheap universal cable from ebay, worked well, but it didn't take long before it began to bind.
I'm on the lookout for a decent quality universal cable if anyone can recommend one ?


rusty nuts - 2/1/08 at 06:56 PM

Push bike brake cable .


Stuart_B - 2/1/08 at 06:56 PM

did you have to put bigger jet's in or drill the main jet out??

Stuart


David Jenkins - 2/1/08 at 07:28 PM

quote:
Originally posted by stuart_
David Jenkins very good info on you site, have you got a infomation about balncing the carbs, as well of what does all the pipes do, and i need to keep and don't?



Stuart,

I haven't got as far as balancing or tuning yet! I'm still doing the installation. That will form part of the last 'chapter', when I get around to it.

If you look through the first 'chapter' on my site, together with the manual from UncleFista/Tony Bond, then you'll know as much as I do!

BTW: Don't under-estimate the other jobs that you may need to do. These could include:

Venting the crankcase somewhere else, if it used to go into the inlet manifold.

Sorting out the vacuum advance (it's harder to set up with 4 inlet pipes). I've got Megajolt ignition, so it's a bit easier.

New throttle & choke linkages.

Have fun...
David



[Edited on 3/1/08 by David Jenkins]


UncleFista - 3/1/08 at 07:47 PM

Cheers Rusty, I'll have a look for one of those then

Stuart, I drilled my jets. Drill bits were from a local engineering company.