[Jeroen]

Originally Posted by srini1785

In the case of a brake / clutch cable , what part of the cable gets "Eaten"?. A cable, as you are well aware , consists of an outer sheath ( tube) which is fixed between two ends while there is a inner multistrand steel wire which moves. This steel wire ( or cable as you can call ) is designed to withstand a stress. .

If there is friction, there is wear. There are at least two kinds of wear on multistrand wire; external and internal wear.

The inner wire moves through the outer sheath. And there is always some resistance, resistance/friction means mechanical wear. Wherever there is more friction you will find more wear. E.g. in the bend of the outer sheath. That is one of the reasons not to bend it too much. Typically the tighter the bend, the more friction, the more wear. So the strands of the wire simply wear away, at some point in time too many strands have worn and the wire will snap!

The shorter the bend, the more friction the more wear. Very often the inner steel wire snaps inside the throttle handle or brake handle. Where the outersheath ends. This is due to the combination of wear and the fact that the cable tends to flexed here as well. The throttle/brake/throtlle handle creates a short of semi-circular motion on the last stretch of the wire.

Steel multistrand cable have internal friction as well. Pulling a multistrand cable puts stress on the internal strands and they move a tiny bit relative to one another, again with some friction.

So to your question; it is literally the individual strands that get eaten/consumerd, both externally and internally due to friction.

To give you are very practical example where steel multistrand cables do get replaced as part of preventive maintenance: Steel hawsers and tow lines on (ocean going) Tugs. The wire will look fine from the outside, but will get replaced due to ongoing internal friction it becomes weaker over time. So we used to replace them after a certain number of hour towing. (Whereas replacing a clutch cable is a simple job, replacing the tow line on an ocean going tug is quite the job. I have done it a few times, and we usually had support from specialist and special tools too.

But do check with the bikers on this forum. Most will be able to confirm that brake / clutch cable/wire snap do happen on a fairly regular basis.

I have only driven a bike for four years. Most of my biking mileage was done in groups and even in that short period I have lost count of the cable snaps we have experienced on our rides. Not myself, I was lucky, but my fellow riders.
Many bikers on this forum, many will read this thread, so maybe you would like to share your experiences here. Have you experienced a cable snapping, or do you know a fellow biker that has?

Over the years I have faced many broken/snapped cables in various situations. next to brake/clutch cables, I have had my fair share of boot/trunk cables snapping and also the occossional fuel filler Cap/door. It happens!

Jeroen

[hrman]

Is it to do with TVS?
I own a Wego. In my 8 years of ownership, the accelerator cable has snapped thrice. On a couple of occasions, I was fortunate to have this happen closer to a service centre.
On another occasion,I had to report this to TVS to come over and tow it to their service station.
It is pretty unsettling to have this happen. Glad it did not cause you too much trouble.

[Lambydude]

Originally Posted by Iyencar

Hello everyone, earlier this morning while riding my scooter to work and found that suddenly I wasn't accelerating no matter how much I twisted the throttle. I was on the Kharghar highway bridge and luckily managed to coast and stop by the side of the road without anything eventful happening. I suspected a broken accelerator cable and called TVS RSA. They sent a mechanic who immediately confirmed that it was indeed a snapped cable and that the scooter would need to be towed. My questions regarding this are:

• I had just had the scooter serviced (paid) 4 days back and since only driven approximately 30-50 kms. Isn't this something that ought to have been checked? Could the service guys have wound it up too tight?
• My scooter has done only 53xx kms and was purchased sometime in the last few months of 2018. It seems way too early for such a critical part to fail. Any thoughts on what would have happened?

The SA says that this part won't be covered under warranty. I plan on writing to the customer care at TVS and asking for this to be covered at no cost and claim a manufacturing defect. Looking forward to any help you guys can give. Thanks!

This is definitely a consummable and cannot be covered under warranty. Snapping of accelerator or clutch cable is not a big issue you need to worried about. Agreed that you will be stranded, but that's a risk which comes along with any vehicle.
Maybe the ownership of a Royal enfield has made me to believe like this. Had multiple clutch and accelerator cable snaps.

[amitjha086]

This has happened to me twice when I owned Yamaha Alba 106. Fortunately, on both the instances, the bike coasted to exactly where the mechanic had his garage. The first time it had snapped, the odometer read over 30,000 km. The second time was around the end of my ownership when I sold it at 54,000 km after four and a half years of use.
This situation can turn dangerous especially when you are in the middle of an overtaking maneuver. A regular replacement of the part before it wears off can save the hassle. I remember servicing my bike from my local mechanic once my free servicing coupons were used out at authorized service center. Probably, the guys at ASS had better idea on when to replace the consumables than the local mechanic.
Interestingly, once my front brake cable snapped just meters after I got it serviced.

[Mr.Boss]

My experience with control cable failure always followed a trend, Less used ones tend to fail sooner (Speaking only about my experience)

Below vehicles never faced cable failures
70k+ used TVS Scooty
Frequently used Apache RTR
35k+ used Yamaha Ray

OTOH below vehicles had cable failures, but gave a clear alarm before they failed
12k (in 5 years) covered RX
- Accelerator became tight and shortly the oil pump cable failed
- Clutch lever was harder - outer sheath started deforming at bends

1.5k (in 8 months) covered Pulsar classic
- Smoothness started deteriorating in clutch operation and the cable failed after few days

Hardly used RXG
- Choke lever stuck, outer sheath damaged near a bend

2k (in 1 year) covered RE-TB
- Clutch cable failed twice. Both occasions the operation was not smooth a few days before they gave off

[ashwinprakas]

Originally Posted by Jeroen

Typically the tighter the bend, the more friction, the more wear.

A very old trick we follow to prolong cable life and to ensure that the cable doesn't snag when turning the bar's etc is to undo the cable from their guides on the chassis and let them hang free, doing so alleviates the bend and reduces internal friction, another advantage of doing so is that it is easy to swap out old cables as you'd not have to remove fuel tank etc in the case of some motorcycles.

Simply tape the outer's together and pull the old one out until the new one is in place.

Might sound petty enough to not mention but trust me, makes a world of difference when it comes to reducing internal friction/drag and prolonging cable life as well as swapping out cables when they're due for replacement.

Cheers,
A.P.

[katchkamalesh]

Originally Posted by Iyencar

Thanks A.P.! Was looking forward to your take on this.

There is a way to predict the failure of these cables.

Clutch and accelerator cables are usually made of multiple cables braided as one and it is highly improbable that all cables fail at once unless it is cut/sliced. In a majority of cases, individual cables snap and as more and more cable snaps, you can feel play when you twist the accelerator or depress the clutch lever, this, my friend, is the symptom of a failing cable.

As you spend more time with your machine, this (free play) should be easy to notice.

[aashishnb]

Theoretically, cables are not consumables.

However, they are usual wear & tear type parts just like your tyres.

Generally, cables now a days last quite long, 10 - 15 years but again it depends on many things - nature of use, weather (moisture increases chances of rusting & jamming), dust, etc.

For e.g. if you do not use your vehicle for a long time and keep it in rain, water will get between the rubber outer sleeve & the metal inner cable/strands. Longer it stays in one place, higher chances of rust & therefore breaking.

The cable most prone to breaking / snapping is the speedometer cable in the analog type meters. They are continuously rotating around their axis within the sleeve. The other one is choke cable as it is not used at all for like really long periods of time.

Accelerator cables not so much.

Off topic,
Old timers would remember, in scooters, the cables would snap anytime. Good thing was the replacement would cost like Rs.10 odd only and the replacement was just the inner steel strand thing which would go in the same outer sleeve. It would take the mechanic 5 mins in total to replace.

Modern ones, where the entire sleeve has to be replaced take more time and opening up a lot of the body parts to put them in their slots along the chassis/fork.

[Jeroen]

Originally Posted by aashishnb

Theoretically, cables are not consumables.

However, they are usual wear & tear type parts just like your tyres.
.

Something tends to be called a consumable if it wears and tears and needs replacing on a regular basis.

Jeroen

[vennarbank]

In my case, when i borrowed a negihbour's TVS 50, the accelerator cable snapped from the handle. Only thing possible was to tie a knot and pull the cable by hand whenever i need to accelerate :-)

[NiInJa]

My Yamaha R15's clutch cable snapped around 5xxx kilometers, couldn't really do anything other than getting it replaced. My Pulsar's clutch cable too gave away at about 20xxx kilometers. Yup, they snap at the most undesirable time. Ask Rohit from 'Kaho naa pyaar hai'

The places they wear out most of the time is at the very start where the cable bends into the outer cover from the lever. If you haven't greased your cables for some time, you will hear a 'kit-kit-kit-kit' sound when pulling (you will need a low noise environment), a sure-shot sign of the cable rubbing somewhere or some of its strands have broken inside the outer cover, in some cases one can feel those tiny vibrations on the palm/fingers. As more and more strands break, the wire will require less efforts to pull which will make you feel it has become smooth but in the end it will snap.

[//HB]

Originally Posted by Iyencar

broken accelerator cable

I ride an Activa, so IF the carb and cable setup is similar, then here's what I can contribute (in very simplistic terms), just in case it helps.

The accelerator cable at the carb side is sort of like a bottle cap (it has to be screwed on to the top of the carb). I had an experience where the threading had worn out, so this just wouldn't stay screwed in, it just popped out and then was replaced with a new cable.

If the setup in your Ntorq is similar, and the incident happened within just days of a service, and that too on a machine that has run such few KMs, my guess says it would most likely be a defective cable or wrongly re-fitted during / after the service. Do ensure to take this up strongly with the company.

[gkveda]

Very interesting discussion on "consumables"

So, Question is, what is a consumable? As far as I know, even Engine, by itself wears out after certain amount of time. Therefore, we do something called "Rebore". Can we consider Engine "Consumable" ?

Tough to answer and accept, but theoretically, Even an Engine is Consumable per above definition.

So, how do we define Consumable?

In my view, any part of the machine is considered Consumable IF and ONLY IF it is CONSUMED by the Engine.

So, ONLY OIL, FUEL and AIR are consumables by definition.

Then, What about, Air Filters, Fuel Filters, Tires, Battery, Brake shoe, Chain, Sprocket (in case of Two wheelers)

Per my understanding, all these are "wear and tear" parts of the vehicle. For few of them, Manufacturer cover under warranty and other few will not be covered under warranty. (Example: Chain and Sprocket will be covered under warranty whereas Filters, Cables are not covered under warranty.

My assumption is, Manufacturers would have taken legal approvals from some authorities as to what "Wear and tear" are covered under warranty and what are NOT covered under Warranty. And for few, there will be warranty on PRORATA BASIS(Example: Tires, Batteries)

So, coming to the point of discussion here, Cables are NOT covered under Warranty and probably because, there is an approval from the Authorities OR BODY of governance.

[Guite]

Cable failure (brake, accelerator, clutch cabkes) is one thing I used to fear most. In more than five years of driving a motorcycle I never had this problem, fortunately. I used to even oil the cable myself; pull back the sleeve on the handle bar and drip some oil on the cables. It will flow down by gravity. If there is no sharp bend and there is less friction between cable and sleeve I believe there is less chance of cable failure.

[hrman]

Bringing up this old thread. My TVS Wego is 10 years old completed 22k kms in my 10 years of ownership, the accelerator cable broke and had to be replaced 4 times. The most recent one being today morning, fortunately it happened in the basement. On the earlier three occasions it happened on the road. The first time was atop a Flyover on the busy bellary road.
I don't know if this is a faulty design or defective product. But reading up on the net shows this is a frequent issue in TVS, the other is the starting battery problem on cold mornings.
But now I've decided to have this cable checked and changed every year during service. It's not a pleasant experience to see this accelerator stop working every two years, especially while driving.