Why dual throttle cables?

[Uncle Flash]

Can anyone tell me why the Keihin FCR carbs on my Ducati 900SS require the dual, push-pull cable system?

[agrid]

in case the spring breaks

[Uncle Flash]

Flatslides are probably better than some carbs mounted on the side of the engine as the heavy slide mechanism could probably close itself off if the spring broke. If it is as simple as a back up for the spring, why don't all carbs use the system?

[BERT]

My Guess

Pull - pull cables are used so a lighter return spring can be utilised and you get a positive action in both directions.
A bit like a desmo throttle cable I suppose.

Bert

[Magilla]

My CBR600RR has dual cables as well.

[agrid]

you answered your own question If the spring breaks on the freeway the slides will 'probably' close... that or you'll keep going till you run out of gas or hit something like a car or preferably the kill switch. I assumed they were a design standard that came in yers ago.

[Sumfun4me]

Bert's explanation sounds about right to me. It's probably got something to do with limiting the stress on your wrist.

[MIK]

I pretty sure it a requirement for new road bikes to have this maybe not here but the US. Its a safety thing, although it also increases responsiveness.

CAMS also a requirement for carby'd cars to run two.

[MattyA]

4 strokes give you power where you want it. 2 strokes are more on off power .
Thats what i figured for dirt bikes anyway

[ranmar850]

You may find it has been a legislative requirement for quite some time, in the interests of safety.

[Nudge]

4 strokes give you power where you want it. 2 strokes are more on off power .
Thats what i figured for dirt bikes anyway

I thought I might have had an answer until I read this. What was the question again?

[gengo]

its the decellaration cable and accelaration cable my new klx250 has it also and thats what it is stated as in manual, sort of like a safety to ensure throttle dont jam and go flat out in case of emergency

[PaulMac]

I have read that under some engine conditions (such as a backfire back up the inlet side) that the spring alone will not close the throttle slides down so the push cable is a safety thing to ensure that throttle closes when you expect it to and under all conditions. 2 strokes don't generally have a push/pull throttle system as they don't usually have problems that the 4 strokes do. It'd also why 4 strokes sometimes have backfire screens in front of the air filter - to stop it catching on fire in the event a a backfire into the airbox. Fun hey!

[Nero Diablo]

Think it might have more to do with CV carbs than flatslide's, which you ducati has OEM. The flatslides are probally set up to run the OEM system for ease of installation, My goose runs twin cables but they are both pull, one fo each carb this was the same arrangment with delorto's bike is a mids 90's design same as the ducati so it would have had to meet the same legislation.