Looking for CBR600 carb info...
David Jenkins - 19/9/07 at 09:24 AM
Right - the CBR600 carbs I won on ebay have now arrived. Pretty good nick as far as I can tell, with no scrapes, mangled screws or obvious damage, and
everything seems to move smoothly and without graunching. Even got a TPS on the end! Not bad for £15 + P&P.
Now I need some info so that I don't mess it up before I even get it on the car! Can anyone help with:
1. Website or manual that gives me some idea of what's what and what goes where.
2. Some idea of how to get it set up reasonably well for running on a 1660cc x-flow in moderate tune.
3. What connector I need for the TPS.
4. Can the carbs be separated? Not urgent, but making a straight manifold is easier than a bent one!
All help gratefully received!
Ta,
David
UncleFista - 19/9/07 at 09:55 AM
quote:
Originally posted by David Jenkins
Right - the CBR600 carbs I won on ebay have now arrived. Pretty good nick as far as I can tell, with no scrapes, mangled screws or obvious damage, and
everything seems to move smoothly and without graunching. Even got a TPS on the end! Not bad for £15 + P&P.
Now I need some info so that I don't mess it up before I even get it on the car! Can anyone help with:
1. Website or manual that gives me some idea of what's what and what goes where.
I have a scan of the fuel section of the Honda manual, just send me your email address and I'll send you a copy.
quote:
2. Some idea of how to get it set up reasonably well for running on a 1660cc x-flow in moderate tune.
Drill the main jet to 1.6-1.65 and see how it runs from there.
quote:
3. What connector I need for the TPS.
Ours must be earlier carbs, they had no provision for TPS, we made our own, just attached the TPS to the throttle spindle and made a bracket.
quote:
4. Can the carbs be separated? Not urgent, but making a straight manifold is easier than a bent one!
If you space them (which looks quite acheivable) the manifold will be easier to make, but spacing the carbs doesn't look like the
"easy" option. We left the carbs and made the manifold to suit 
quote:
All help gratefully received!
Ta,
David
[Edited on 19/9/07 by UncleFista]
David Jenkins - 19/9/07 at 02:47 PM
I'm feeling a little overwhelmed... 
Had a good look at the carbs and I'm starting to learn what the bits are - but there seem to be pipes everywhere! I haven't even worked out
where the fuel goes in yet.
I looked at the manual Tony sent me, which helps, but there seem to be pipes connected to the coolant plumbing, others to do with air bleeds, etc.
Still - I guess I'll work it out soon enough...
Any benefit to having the original airbox, or is it unlikely to fit under my bonnet? It's just that the breaker's got one of them for sale,
and the auction runs out in 3 hours...
[Edited on 19/9/07 by David Jenkins]
UncleFista - 19/9/07 at 03:26 PM
quote:
Originally posted by David Jenkins
I'm feeling a little overwhelmed...
Had a good look at the carbs and I'm starting to learn what the bits are - but there seem to be pipes everywhere! I haven't even worked out
where the fuel goes in yet.
I looked at the manual Tony sent me, which helps, but there seem to be pipes connected to the coolant plumbing, others to do with air bleeds, etc.
Still - I guess I'll work it out soon enough...
Any benefit to having the original airbox, or is it unlikely to fit under my bonnet? It's just that the breaker's got one of them for sale,
and the auction runs out in 3 hours...
[Edited on 19/9/07 by David Jenkins]
It's much simpler than it seems, as far as I remember, all pipes/tubes bar the fuel supply are left open to the atmosphere.
I'll have a look later, but I'm pretty sure it's that simple 
DarrenW - 19/9/07 at 03:30 PM
Did your carbs come with the trumpets (rubber on mine). If not then the air box might include these.
I just bought the trumpets and plastic back plate then modded a filter to attach to this. If the trumpets are not seperate then spacing the carbs
could be tricky 9at a guess).
I drilled my main jets to 1.6mm, needles in centre, air screws 2.5 turns out and blocked off an air hole. This ran ok with zzr1100 on pinto. Not sure
how this equates to your set up.
Ref pipes, mine had some for the heating which i junked. Some for fuel which i connected up to my fuel supply (there was one connection in the centre
that split into 2, each feeding a rail between 2 float bowls). After that there are another 2 pipes (each feeding a pair of carbs) that i think were
connected to the airbox.
What make are the CBR carbs? Soemone may have similar from a different bike that can help better.
David Jenkins - 19/9/07 at 03:42 PM
It looks like they're Keihin carbs. The bike they came from was a 1999 Honda CBR600F-X, which I think was the last carb model before they went
over to throttle bodies.
I've got the trumpets, but I can't see how I would fit an air filter mounting plate around them. I don't seem to have the 2 lengths of
pipe that supply the fuel, unfortunately.
Still, it's all a learning experience!
DarrenW - 19/9/07 at 03:45 PM
Might needs some pics if you can oblige. mine are kehins too so may be some similarities.
Air filter took some thinking about but i sussed it in the end.
robertst - 19/9/07 at 04:01 PM
quote:
Originally posted by David Jenkins
Not bad for £15 + P&P.
£15? R1 carbs are going for at least £100... i've been two weeks looking on ebay for carbs...
David Jenkins - 19/9/07 at 04:05 PM
Some piccies...
CBR600FX carbs, as delivered
CBR600FX carbs
CBR600FX, side view
David Jenkins - 19/9/07 at 04:06 PM
quote:
Originally posted by robertst
£15? R1 carbs are going for at least £100... i've been two weeks looking on ebay for carbs...
It helps to aim low...
...everyone wants the bigger ones, fewer people want the smaller ones!
jack trolley - 19/9/07 at 06:09 PM
Complete
ZZR1100 engine for £300
UncleFista - 19/9/07 at 09:20 PM
quote:
Originally posted by robertst
quote:
Originally posted by David Jenkins
Not bad for £15 + P&P.
£15? R1 carbs are going for at least £100... i've been two weeks looking on ebay for carbs...
Mine were £15 *including* P+P (finished on 99p) although I didn't get the bits of rubber hose to join to the manifold or the trumpets, or the
TPS...
David Jenkins - 20/9/07 at 08:03 AM
Looking at the instructions, it mentions a 'SE valve' which is a slide on the top that operates a piston on each carb. Is this the choke?
Does it mean 'Starting Enrichment' or something like that?
DarrenW - 20/9/07 at 08:11 AM
i believe it is. On mine the slide is above the joining rubbers, just below the black plastic vacuum piston tops. It operates horizontally and pulls a
small 'piston' on each carb maybe 10mm or so. There will be a cable attachment and should be a small diameter return spring to pull it back.
It looks the same as in your pics.
Ive not connected mine up yet but if its been laid up a couple of days i have to pull the slide open to start and then shut it off after only 15 secs
or so.
David Jenkins - 20/9/07 at 08:15 AM
One more question! 
The carbs originally had 2 throttle cables - one to pull them open, and the other to pull them shut. This seems to be quite common on bike carbs.
How have people managed in a car? Presumably everyone uses just 1 cable, maybe with a return spring?
Photos would be appreciated!
David
DarrenW - 20/9/07 at 08:18 AM
On your pice it looks like the fuel pipe is there. The heater pipe looks like the one that connects to either outer ends of the carbs (Y connector in
the middle), the fuel one looks like it could be the pipe that connects between 1+2 and 3+4. You may be able to check it by carefully taking a float
bowl off and blowing down the pipe - moving the float should control the air going in.
DarrenW - 20/9/07 at 08:40 AM
Cables - yes i have just used the one pull cable with return spring. I ended up buying a mixed box of springs so i could get one that worked OK. It
ended up being quite strong (an old weaker one didnt shut the butterfly off quick enough).
I found the cable kit from Mac#1 to be top notch and has adjusters for carb end and also pedal end.
Sorry, i dont have a pic of the spring. Im away from tonight so wont be able to post one till next week
RoadkillUK - 20/9/07 at 06:20 PM
Same thing here, just the one cable and a spring, it's not too strong but it's enough to pull the cable back.
David Jenkins - 21/9/07 at 02:05 PM
quote:
Originally posted by DarrenW
On your pice it looks like the fuel pipe is there. The heater pipe looks like the one that connects to either outer ends of the carbs (Y connector in
the middle), the fuel one looks like it could be the pipe that connects between 1+2 and 3+4. You may be able to check it by carefully taking a float
bowl off and blowing down the pipe - moving the float should control the air going in.
It looks like the fuel pipes are the ones I haven't got! I can see where they go though, so it's no hardship - just some pipe and a
T-piece.
The other small pipes are for some form of air bleed (I think) that probably went into the airbox.
As for the big heater pipes - does anyone use them? I can't see that it would be a good idea to permanently connect them to the engine's
coolant system, as I'd get the petrol boiling - I guess they're only for de-icing. Maybe there was a thermostat of some kind on the
bike.
Good game though - I've spent most of the afternoon stripping down the carbs, cleaning and checking them. One had a sticking butterfly and there
were a few rusty bits to sort, but at least now I know that all the diaphragms are intact, the slides are clean and all the passageways clear.
Carb cleaner's a bit potent though, even with the garage door wide open... coff!
