Topic: double to single throttle cable?

[MattFreeman]

Has anyone removed their "push" throttle cable? I would like to do so on my 750 and was wondering if there are any considerations that needed to be made? Like putting a spring on the linkage, or will the weight of the valve body be enough to decrease the gas?

Any thoughts or experience?

[Deltarider]

I've a brand new push cable still packed. Never bothered to install it. Maybe I can use it as a pull cable in the future.

[ekpent]

Some of my bikes do not have the push cable,no problems here.Sad to say but the push can not be used as a pull,think the hook-up at handle is different.

[MCRider]

Has anyone removed their "push" throttle cable? I would like to do so on my 750 and was wondering if there are any considerations that needed to be made? Like putting a spring on the linkage, or will the weight of the valve body be enough to decrease the gas?

Any thoughts or experience?

What bike?

In any case, the "B" cable does nothing and is just along for the ride...unless the carbs stick open and the "B" cable will close them. The standard spring should be fine for use without the "B" cable as, the "B" cable does nothing and is just along for the ride...

If you have CV type carbs, a heavier spring still won't help, if the slide sticks, it sticks.

The "B" cable is a safety item, so remove it with the same conviction as not wearing a helmet, or a seat belt.

I can go either way. Right now, all my bikes have B cables. Properly set up, it should not interfere in any way with your throttle, so why not?

[Deltarider]

The "B" cable is a safety item, so remove it with the same conviction as not wearing a helmet, or a seat belt.

Are you serious?
I can't see how the (far to) heavy spring on the carbs can ever fail. Just take a look.
I believe it was just another thing to satisfy American regulations. Where else does one find rear view mirrors that are partly obscured by... text (Objects in this mirror... etc.) So you can read whilst driving. Some safety device. Only in the United States of Absurdistan.

[MattFreeman]

Properly set up, it should not interfere in any way with your throttle, so why not?

Thanks for the input. I just wanna eliminate any clutter that I can.

[MCRider]

Properly set up, it should not interfere in any way with your throttle, so why not?

Thanks for the input. I just wanna eliminate any clutter that I can.

If I walked up to a bike with no B cable and fliipped the throttle and it snapped back like it should, I wouldn't say boo about the missing cable. Personally. To each there own.

There will be those who say, "Oh No! Never!" and they have a point.

[andy750]

In my experience its not so good not to have a B cable. Unless your carbs are spotlessly clean and the idle will always return to 1000-1100 rpm then you`ll find a "hanging" idle after a long ride or even around town. If you have the B cable present you can twist the throttle to "push" the carbs and return idle to normal. Obviously you cant do that if B cable is removed and instead you sit there at the lights with a high idle....at least that was my experience...never again!

cheers
Andy

[edbikerii]

Yes, my experience is the same.  I'd keep the B cable for this reason alone.  However, I'd love to know the real cause for this issue and resolve it.  I've never bothered, as I've just got too many other things to do.  I just push the throttle closed with the lever at stop lights.

I just want to point out, however, that I've never seen a car with such a "safety device".  Considering how many cars there are on the road with no single-cable safety issue, perhaps there is some other reason to have the B cable on the bikes?

Oh, and swapping the push cable to the pull does not work on the 77-78 CB550.  I found out the hard way.  The cables are different lengths and don't fit over the throttle wheel.

In my experience its not so good not to have a B cable. Unless your carbs are spotlessly clean and the idle will always return to 1000-1100 rpm then you`ll find a "hanging" idle after a long ride or even around town. If you have the B cable present you can twist the throttle to "push" the carbs and return idle to normal. Obviously you cant do that if B cable is removed and instead you sit there at the lights with a high idle....at least that was my experience...never again!

cheers
Andy

[MCRider]

Yes, my experience is the same.  I'd keep the B cable for this reason alone.  However, I'd love to know the real cause for this issue and resolve it.  I've never bothered, as I've just got too many other things to do.  I just push the throttle closed with the lever at stop lights.

I just want to point out, however, that I've never seen a car with such a "safety device".  Considering how many cars there are on the road with no single-cable safety issue, perhaps there is some other reason to have the B cable on the bikes?

Oh, and swapping the push cable to the pull does not work on the 77-78 CB550.  I found out the hard way.  The cables are different lengths and don't fit over the throttle wheel.

In my experience its not so good not to have a B cable. Unless your carbs are spotlessly clean and the idle will always return to 1000-1100 rpm then you`ll find a "hanging" idle after a long ride or even around town. If you have the B cable present you can twist the throttle to "push" the carbs and return idle to normal. Obviously you cant do that if B cable is removed and instead you sit there at the lights with a high idle....at least that was my experience...never again!

cheers
Andy

Yes edbiker, there is a problem if the throttle doesn't perform flawlessly without the B cable. It may be tricky to find, and not worth the time.

Interesting point about the car. And I seem to remember AUDI had a problem with runaway cars several years back. Still no dual cable systems.  Would the driver have to slip their foot into a sandal like gas pedal?   

[Deltarider]

Oh, and swapping the push cable to the pull does not work on the 77-78 CB550.  I found out the hard way.  The cables are different lengths and don't fit over the throttle wheel.

Thanks for clearing that, Ed. I feared so already. Anyone who wants to trade my genuine B cable in it's original packing for an A cable?  

[TwoTired]

If you want to stop the bike when the single carb return spring breaks, keep the "B cable".  The pull ("A") cable doesn't really push the slides down well, and springs do break.  Any piece of metal wire that is constantly bent will eventually break from metal fatigue.  The timing of such a break is usually when least desirable.
The early 750 and many other carbs, has a spring on each carb slide to close them.  If a single spring broke, the engine would still be controllable.  So, the single actuation cable they have, does not factor into positive slide closure. 

When the 4 carb set was converted to a common shaft actuation arm arrangement, 4 individual slide springs were removed and replaced with a single common return spring.  A single point of failure can make the engine uncontrollable, so a positive return cable was added.  The brakes alone aren't going to stop a screaming 750 motor.  If the return spring breaks while in an inside turn with oncoming traffic...splat.  (Just think about all the times where cutting engine power was essential for survival.)

If you remove the ""B" cable, then for safety sake add the return spring replacement as a routine replacement item, say every 5 years (A guess... I don't really know the MTBF of a throttle spring) and be certain to NOT nick the wire anywhere along its length to instigate a metal fatigue fracture point.  You don't really want to gamble that the spring will last forever (it definately won't) and replacement should be at a time of your choosing, not the random point where the metal fatigues to the point of failure.

You can use the "B" cable as an "A" cable for emergency purposes on a CB500/550 with the early non-PD carbs.  The throttle will work backwards, but you can control the engine speed.

Ride safe!!

[Markcb750]

What TT said plus it makes the twist throttle feel more directly connected to the slides of the carburetors, it helps the twist throttle return when backing off throttle.

This provides a "sharp & smooth" slide response to twisting the grip without the need to incorporate a larger return spring, reducing hand fatigue.

[ekpent]

Keep your KILL switch button working also-and learn how to use it       PS- Keep them both lubed well-more cable more drag. Anybody ever have a spring break - no not in Florida but show us pics----

[TwoTired]

I've heard the kill switch argument before.  And yes, it CAN bail you out.  But, it takes time.  At 60mph, each second of delay is 88 ft traveled.  How fast can you notice, diagnose, and effect the alternate plan for stopping a runaway engine?  Further, anyone who's done some high G turns knows that even small engine power changes make a big difference in the line traveled around a turn.  If you are off your line where will your wheels be after 160 ft traveled?

Still, the kill switch is probably a reliable option for the super human.  I haven't been superhuman since age 25, though.  So, I'll keep the pull cable.  That's my decision, anyway.

Cheers,

[Retro Rocket]

The "B" cable is a safety item, so remove it with the same conviction as not wearing a helmet, or a seat belt.

Are you serious?
I can't see how the (far to) heavy spring on the carbs can ever fail. Just take a look.
I believe it was just another thing to satisfy American regulations. Where else does one find rear view mirrors that are partly obscured by... text (Objects in this mirror... etc.) So you can read whilst driving. Some safety device. Only in the United States of Absurdistan.

It wasn't just an American thing, these bikes had dual throttle cables world wide. I have had the tab area of the spring fail {where the spring connects to the throttle linkage}. When looking at the broken spring i noticed that it had worn away enough to cause it to break.

Mick

[Inigo Montoya]

I choose to keep the push as well for safety concerns. Besides, my throttle works so smoothly and easily that if I let go of it, it will snap shut immediately. It is operable with just 2 fingers and thats it. But you still never know. I know that could be said about anything on a bike and I am sure the NO push cable camp will say such, but the difference is that for the throttle to fail, I have to create the conditions for it to fail. Removing the push cable does such a thing.

If someone wants to remove, the bike will still work just fine but they should be aware that a safety net is gone.

[edbikerii]

The OEM Honda cables are teflon lined and lubing them can ruin the lining.  I bought new cables and just use them dry.  I've heard of dry gun lubricants (graphite?) being used on the cables successfully, but my experience has been good with OEM Honda cables dry.

...
PS- Keep them both lubed well-more cable more drag.
...

[ekpent]

I can feel the flames,guess I am a goner.See you in the obituary. Have ridden 750's since the 70's,some with a lubed single cable.Well when I am gone come to my auction.

[edbikerii]

I've never lubed an OEM Honda throttle cable and ruined it, so I don't know.  Just hearsay.  I have ruined a Motion-Pro clutch cable by lubing it, though.  It didn't even last a month before gumming up and snapping, leaving me stranded for the second time.

I can feel the flames,guess I am a goner.See you in the obituary. Have ridden 750's since the 70's,some with a lubed single cable.Well when I am gone come to my auction.

[Retro Rocket]

i imagine a silicon lubricant wouldn't hurt the teflon lined cables at all. In saying that i have always lubed my cables and like Inigo have always had a very light action for my throttle, heavy throttles slow carb response making your bike less responsive.

Mick

[ekpent]

Lets not start an OIL thread Anybody here ever bought an old Honda that has been sitting for around 2-5-10- years and maybe all the moving things need a little help-  Like me after a FUN night out---

[edbikerii]

Hey, I'm not arguing one way or the other.  Just talking from my own experiences and preferences.  It is your bike, you do what you want with it.

[ekpent]

"It didn't even last a month before gumming up and snapping, leaving me stranded for the second time."
What happened the first time???

[Markcb750]

"It didn't even last a month before gumming up and snapping, leaving me stranded for the second time."
What happened the first time???

It must be binding or rubbing some place, the cables should last for 10s of thousands of miles with or without lube.

Check cable routing
Check alignment of cable guides and rotating mechanisms.
Make sure noting can pinch cable, like the tank or triple tree.

[edbikerii]

Of course!  Cables should last for 10s of thousands of miles, as they have on all of my other bikes/cars/etc.  That's why I posted this.

All this occurred very soon after I purchased the bike.  The prior cable had been lubed by a previous owner, as there was gummy, black lube residue visible at the lever end of the cable.  On the day I bought the bike, I remember thinking, "damn, this little bike has a really hard clutch pull -- or am I just a wimp?".  I tried lubing the cable (I even bought the stupid little cable lube tool and spray) to make it smoother, but there was no discernable difference.  The cable broke soon thereafter.

Then, as discussed, I replaced it with a Motion Pro cable, and lubed it.  It broke within about a month.

I replaced that cable with an OEM Honda cable, installed it using the same routing (per shop manual), and it has lasted beautifully for nearly fifteen years with no lube.  Granted, she resides indoors now, and doesn't get ridden daily in such adverse conditions anymore.

I blame the premature failure of the Motion Pro cable on the lube, which was advertised as being for chains and cables.  I don't remember the lube type or brand offhand.  I used to live in New York City at the time, so the bike used to reside outdoors, so was subject to snow, rain, extremes of heat and cold (6F to 100F), dust, emissions, etc.  I believe that the lube gummed up badly, and the cold made the lube even less viscous.

When I installed the OEM Honda cable (dry), I remember being really impressed with how easy the clutch pull became.  It was like night and day.  It still is, nearly 15 years later.

Again, this is just my opinion (based on my direct observation), but I believe that the lube attracts dirt and gums up, shortening the life of the cables.  I've also read (here on these forums and elsewhere, including BMW forums) that OEM Honda cables have Teflon linings and require no lube.  They should last quite a long time, but when they are done, they are done.  I've read (hearsay?) that some lubes may, in fact, cause the Teflon linings to separate and fail, causing premature failure.

Your mileage may vary.

Ed

"It didn't even last a month before gumming up and snapping, leaving me stranded for the second time."
What happened the first time???

It must be binding or rubbing some place, the cables should last for 10s of thousands of miles with or without lube.

Check cable routing
Check alignment of cable guides and rotating mechanisms.
Make sure noting can pinch cable, like the tank or triple tree.

[mystic_1]

Where did the cables break?

mystic_1

[edbikerii]

both right near the lollipop end in the lever.

Where did the cables break?

mystic_1

[TwoTired]

That "lollipop" is supposed to turn freely in the clutch lever socket in order to keep the cable itself from experiencing sharp bending.  A bit of lube on that, or careful fitment/shaping to ensured its rotation capability, can save some cables from breakage.
 Bend a wire often enough and it will fatigue and break.

FYI

[Markcb750]

Of course!  Cables should last for 10s of thousands of miles, as they have on all of my other bikes/cars/etc.  That's why I posted this.

All this occurred very soon after I purchased the bike.  The prior cable had been lubed by a previous owner, as there was gummy, black lube residue visible at the lever end of the cable.  On the day I bought the bike, I remember thinking, "damn, this little bike has a really hard clutch pull -- or am I just a wimp?".  I tried lubing the cable (I even bought the stupid little cable lube tool and spray) to make it smoother, but there was no discernable difference.  The cable broke soon thereafter.

Then, as discussed, I replaced it with a Motion Pro cable, and lubed it.  It broke within about a month.

I replaced that cable with an OEM Honda cable, installed it using the same routing (per shop manual), and it has lasted beautifully for nearly fifteen years with no lube.  Granted, she resides indoors now, and doesn't get ridden daily in such adverse conditions anymore.

I blame the premature failure of the Motion Pro cable on the lube, which was advertised as being for chains and cables.  I don't remember the lube type or brand offhand.  I used to live in New York City at the time, so the bike used to reside outdoors, so was subject to snow, rain, extremes of heat and cold (6F to 100F), dust, emissions, etc.  I believe that the lube gummed up badly, and the cold made the lube even less viscous.

When I installed the OEM Honda cable (dry), I remember being really impressed with how easy the clutch pull became.  It was like night and day.  It still is, nearly 15 years later.

Again, this is just my opinion (based on my direct observation), but I believe that the lube attracts dirt and gums up, shortening the life of the cables.  I've also read (here on these forums and elsewhere, including BMW forums) that OEM Honda cables have Teflon linings and require no lube.  They should last quite a long time, but when they are done, they are done.  I've read (hearsay?) that some lubes may, in fact, cause the Teflon linings to separate and fail, causing premature failure.

Your mileage may vary.

Ed

"It didn't even last a month before gumming up and snapping, leaving me stranded for the second time."
What happened the first time???

It must be binding or rubbing some place, the cables should last for 10s of thousands of miles with or without lube.

Check cable routing
Check alignment of cable guides and rotating mechanisms.
Make sure noting can pinch cable, like the tank or triple tree.

If it failed that quickly you have something misaligned or binding.  MotionPro cables are fine, I have been running over a year., 5000 mi.

[Inigo Montoya]

I am doing an old honda cable for clutch but motion pro for throttle and it is so nice.

[dave500]

im running both cables,ive have the pull cables locknut come loose and cause a non full returning throttle on a twisty road just cruising and it takes you by surprise,i fixed it on the road side ok,if the spring broke in traffic with a handfull of throttle with no b cable the room for error is much less ,i wonder what regulations at race tracks pertain to these bikes or carby type are?

[edbikerii]

Yes, that makes sense.  I just assumed the excessive force required to overcome the friction caused mine to break, though.  Certainly could have been a combination the force plus work hardening at the lollipop, of course.

That "lollipop" is supposed to turn freely in the clutch lever socket in order to keep the cable itself from experiencing sharp bending.  A bit of lube on that, or careful fitment/shaping to ensured its rotation capability, can save some cables from breakage.
 Bend a wire often enough and it will fatigue and break.

FYI

[Deltarider]

Tip: when adjusting the clutch cable at the handlebar, make sure the slot in the fixing nut (near the adjuster) faces back- or downwards, so water and dirt can't enter here.

[edbikerii]

Hey, I found the old thread about dri-slide and cables:

http://forums.sohc4.net/index.php?topic=27530.msg280981#msg280981