View Full Version : Throttle Cables... Do we really need 2?


kkim
December 9th, 2008, 02:24 PM
I know for legality reasons, street bikes are required to have a push/pull throttle cable arrangement, which our bikes does have.

My question... Can I get rid of the "push" cable and not suffer ant ill effects? I've done this to my single cylinder CV carbed dirt bike and have had no problems.

Has anyone done this and have you run into problems because of this?

Why remove it?? One less cable to adjust, one less failure point, less weight. :D

Alex
December 9th, 2008, 02:32 PM
While you're at it, make sure to remove the cotter pins on the front and rear axle castle nuts; that's good for another 5 - 6 grams. :p

kkim
December 9th, 2008, 02:35 PM
I'm serious.. do we need the second cable?

camaroz1985
December 9th, 2008, 02:35 PM
less weight. :D

That's the key right there :thumbup:

I don't have any experience with this on bikes, but from my experience with small bike engined cars we only ever used one. As long as there is enough return force in the springs you should be ok. I guess just another reason to make sure your cables are in good shape and clean.

Alex
December 9th, 2008, 02:53 PM
I know for legality reasons, street bikes are required to have a push/pull throttle cable arrangement, which our bikes does have.

It's actually not a legal requirement. Some Ducati motorcycles, even recent ones, have come with only single throttle cables. But doing the mod on a bike that came with a push/pull setup doesn't seem wise to me. Of course it's OK as long as nothing happens with that single cable that's left. And in the scheme of things, having the throttle do something unexpected (or not respond as expected) on a ninjette is probably much less dangerous than on a literbike. But I don't get going through the trouble to simplify the maintenance (takes 2 seconds to adjust both cables), or the weight (inconsequential). Heck, weigh a Corbin seat and a stock seat, and see whether it's necessary to remove 30 or 40 throttle cables to make up the difference. ;)

kkim
December 9th, 2008, 03:03 PM
It's actually not a legal requirement. Some Ducati motorcycles, even recent ones, have come with only single throttle cables. But doing the mod on a bike that came with a push/pull setup doesn't seem wise to me. Of course it's OK as long as nothing happens with that single cable that's left. And in the scheme of things, having the throttle do something unexpected (or not respond as expected) on a ninjette is probably much less dangerous than on a literbike. But I don't get going through the trouble to simplify the maintenance (takes 2 seconds to adjust both cables), or the weight (inconsequential). Heck, weigh a Corbin seat and a stock seat, and see whether it's necessary to remove 30 or 40 throttle cables to make up the difference. ;)


I find it quite a pain to get the cables adjusted correctly and if you have one correct and the other incorrect, the net result is that it's out of adjustment. The worse that could happen if the single cable breaks is that the bike will go back to idle... the same in a push/pull setup.

I'm looking for reasons for why I need to keep it that may affect the bikes proper operation or ridability.

From the reasons you stated, you're keeping it just cause it's there. :)

Alex
December 9th, 2008, 03:11 PM
I find it quite a pain to get the cables adjusted correctly and if you have one correct and the other incorrect, the net result is that it's out of adjustment. The worse that could happen if the single cable breaks is that the bike will go back to idle... the same in a push/pull setup.

I'm looking for reasons for why I need to keep it that may affect the bikes proper operation or ridability.

I'm not sure that's the case. With two cables (one push/one pull) + the return spring, there are 2 levels of protection. For the throttle to be applied against the rider's wishes, one of the cables needs to break and the return spring needs to break. (and the return spring is quite light on ninjettes).

Removing one cable means there's one less safety net. And even in a non-critical situation, it's one less component that may be used to idle the bike home carefully (if we notice one cable has snapped but the throttle is still mostly usable with one left). We can debate the likelihood of any cable (or return spring) failing under normal usage, but these types of things are designed for that 1 in a 1000 shot, not because it's expected to happen on 9 out of 10 bikes.

From the reasons you stated, you're keeping it just cause it's there. :)

From the reasons you've stated, you're considering modding it because you have run out of other things to do to the ninjette. :D

camaroz1985
December 9th, 2008, 03:12 PM
This is getting good :popcorn:

kkim
December 9th, 2008, 03:19 PM
With two cables (one push/one pull) + the return spring, there are 2 levels of protection. For the throttle to be applied against the rider's wishes, one of the cables needs to break and the return spring needs to break. (and the return spring is quite light on ninjettes).

What are the chances of a cable and spring breaking at the same time?

I think this is a more plausible answer as to why most bikes have this crazy setup... (found on the web)

I did find out that some time ago that Honda was in a law suit and lost because of a throttle stick(single cable).After this it seemed that the dual cable came out and everyone jumped on the band wagon. If a throttle would ever stick it will be because of lack of maintenance.

Alex
December 9th, 2008, 03:26 PM
What are the chances of a cable and spring breaking at the same time?

Infinitesimally low. But what are the chances of the cable breaking (or almost breaking) and a rider not noticing it right up until the spring fails as well? Low, but not as low as a spontaneous coincidental failure of both.

And these cables were spec'd for a bike that the designers knew would have two of 'em. I wonder if more care is put into the cable design (thickness, materials, and attachment points) for bikes that don't use the push/pull setup.

Even the new Yamaha throttles that are running an electronic sensor to measure throttle activity and a stepper motor to control the throttle plates still have both a return spring and manual cable in place to positively confirm that the throttle plates are closed when the rider rolls off.

kkim
December 9th, 2008, 03:38 PM
But what are the chances of the cable breaking (or almost breaking) and a rider not noticing it right up until the spring fails as well? well, if there was only one cable, you would know as soon as the single cable broke. In your scenario, you still wouldn't be able to ride the bike with only a push cable.


And these cables were spec'd for a bike that the designers knew would have two of 'em. I wonder if more care is put into the cable design (thickness, materials, and attachment points) for bikes that don't use the push/pull setup.. Good point. I'll be sure let you know when the single cable fails. :) I've been running with a single cable on the dirt bike w/o problems. Granted it's a 2006, but I think proper maintenance is the key rather than adding an extra cable to ward off the liability claims.



Even the new Yamaha throttles that are running an electronic sensor to measure throttle activity and a stepper motor to control the throttle plates still have both a return spring and manual cable in place to positively confirm that the throttle plates are closed when the rider rolls off. Is that with one cable or two? :)

Alex
December 9th, 2008, 03:57 PM
Is that with one cable or two? :)

It needs zero yet has one. Just like us needing one and having two. :D

kkim
December 9th, 2008, 04:05 PM
It needs zero yet has one. Just like us needing one and having two. :D

... and yet cars make do with zero. :ohno:

thanks... you just answered my question... we only need one. :)

Alex
December 9th, 2008, 04:08 PM
... and yet cars make do with zero. :ohno:

thanks... you just answered my question... we only need one. :)

Stuck throttle in a curve with a car doesn't cause it to tip over in a microsecond, and you've got 8 airbags around you "just in case" anyway :) And truthfully, we only need a helmet if we smack our heads on something, right? :eek:

To me, and maybe only to me, this seems like the Harley guys opposing ABS not for any philosophical reason other than the cable running to the front wheel and the small disk, so Harley had to design a completely invisible system for it to be accepted with the magnets in the carrier bolts. We take enough risk as it is deciding to hop on a bike instead of taking the car; removing safety measures on the bike for aesthetics alone isn't a path I'd choose or recommend. :2cents:

kkim
December 9th, 2008, 04:39 PM
And again, look at my original post. It was asking if removing the push cable affected the operation of the bike or caused problems. Whatever views you hold on how safe your bike needs to be before you jump on it is a personal preference and you are certainly entitled to your opinion.

So, if I run with only one cable... you gonna be okay with it? :D

HKr1
December 9th, 2008, 04:40 PM
Only time I didnt use the push/pull cable is when I swapped out the stock carbs for CR's. I was just being lazy & not hooking up the second,,,, Never really worried about thou. If any carbs needed two, I would think that type would before a CV type.

kkim
December 9th, 2008, 04:42 PM
If any carbs needed two, I would think that type would before a CV type. Why would the CV carb make a diff?

VeX
December 9th, 2008, 04:58 PM
Not only do I believe in the redundency of two throttle cables, I threw another one in there JUST to be safe! :thumbup:

kkim
December 9th, 2008, 05:00 PM
Not only do I believe in the redundency of two throttle cables, I threw another one in there JUST to be safe! :thumbup:

somehow, I think you would be able to figure out a way to do that. :p

HKr1
December 9th, 2008, 05:30 PM
Why would the CV carb make a diff?

Casue on a CV, the throttle cables dont even open/close the slides directly :)

kkim
December 9th, 2008, 07:12 PM
Casue on a CV, the throttle cables dont even open/close the slides directly :)

so what difference would it make if it's one or two cables connected to do a job that it doesn't do in the first place? not trying to be a wise ass... just trying to make sure I won't run into a problem if I take the push cable off to experiment.

RaceBikeRentals
December 9th, 2008, 08:00 PM
I honestly have no idea if you can go with just one cable; out of all the bikes I've owned, I've never even lubed a throttle cable or had one break. Hard for me to imagine why you would even think about removing one Kelly, but guess you are just looking for ways to save weight when you get here next year to race one of my bikes :)

kkim
December 9th, 2008, 08:09 PM
I honestly have no idea if you can go with just one cable; out of all the bikes I've owned, I've never even lubed a throttle cable or had one break. Hard for me to imagine why you would even think about removing one Kelly, but guess you are just looking for ways to save weight when you get here next year to race one of my bikes :)

lol... With the number of bikes you have, I would think you would have ripped out the extra cable just so you could set the throttle cable slack faster and easier on all the bikes you need to attend to.... or do you not even touch those?

I'll be installing a quick turn throttle shortly and debating about removing the extra cable while I'm in there.

HKr1
December 10th, 2008, 08:47 AM
so what difference would it make if it's one or two cables connected to do a job that it doesn't do in the first place? not trying to be a wise ass... just trying to make sure I won't run into a problem if I take the push cable off to experiment.

Your always a wise ass :p I dont really see a diff ....... And Iam sitting here thinking... arnt these a pull/pull type thing :)