Author Topic: throttle cable fail at 75 mph  (Read 1443 times)

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Offline evinrude7

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throttle cable fail at 75 mph
« on: February 12, 2022, 06:48:07 AM »
last night i was heading home from the work week and my throttle cable gave up the ghost.  luckily i had a fairly clear path to the shoulder of the highway.  after an hour and a half of trying to decide if i should have the wife come with the pickup or wait for a free tow through my insurance (which after an hour they hadn't even assigned a truck) i turned the idle set screw up to 3K then 4K after i got moving and meandered the back roads home.  top speed down hill was maybe 45 but mostly i was going about 20-30 waving cars around me all the way.  the cable busted loose at the clam shell and i could not figure out a fix.  has anyone had this happen at the top of the cable and macgyvered a way to get it working again while stuck on the side of a highway?
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Offline bryanj

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Re: throttle cable fail at 75 mph
« Reply #1 on: February 12, 2022, 07:16:46 AM »
Dont matter where it breaks there aint enough  free play to do anything with
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Offline BenelliSEI

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Re: throttle cable fail at 75 mph
« Reply #2 on: February 12, 2022, 07:21:22 AM »
Never tried this, but could you swap in the “push cable” (stupid name) and ride home twisting the grip backwards? I wonder......

Offline PeWe

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Re: throttle cable fail at 75 mph
« Reply #3 on: February 12, 2022, 07:28:44 AM »
Time to replace both cables.
My K6 got new low priced aftermarket Slinky Glide cables 2013.

When a throttle cable gave up for many years ago, I just increased idle and rode it home, good speed.

I have extra spare cables in my garage and avoid waiting if any cable will give up.
« Last Edit: February 12, 2022, 07:32:14 AM by PeWe »
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline ekpent

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Re: throttle cable fail at 75 mph
« Reply #4 on: February 12, 2022, 08:19:28 AM »
You did good to get her home.Broken clutch cables are a pain also,been there done that also -  :D 
   When I was a kid and had a Suzuki 125 my dad took the bike and I down to a relatives farm. The throttle cable broke and I wanted to keep riding so I rigged the throttle cable up to the from brake lever and kept riding with that. I remember riding in some corn and the first stalk I hit with the lever put me wide open for a second. After that I was more careful with a finger on the front and back !  ;D
« Last Edit: February 12, 2022, 08:27:20 AM by ekpent »

Online carnivorous chicken

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Re: throttle cable fail at 75 mph
« Reply #5 on: February 12, 2022, 08:22:07 AM »
You did good to get her home.Broken clutch cables are a pain also,been there done that also -  :D

I keep an old clutch cable under the seat. And after a couple incidents of failed cables give them a look every once in a while. In my experience they usually fail at the barrel near the grip, and you can see fraying before they go.

Offline ekpent

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Re: throttle cable fail at 75 mph
« Reply #6 on: February 12, 2022, 08:31:09 AM »
My first ride on a 1973 GT750 Suzuki I had made roadworthy malfunctioned at the clutch arm behind the cover while I was around 30 miles from the shop. Rolling stops and  timing up a couple of red lights got me back.Gotta love a constant mesh trannie.  ;)

Offline PeWe

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Re: throttle cable fail at 75 mph
« Reply #7 on: February 12, 2022, 08:48:24 AM »
I got a clutch issue too around 6 years ago.
 It was the clutch adjuster screw with inner stuff inside outer clutch cover that caused an issue with no working clutch. Cable was not much used and still OK.

CB750 work really fine to shift up without clutch. Just a quick throttle release and shift.
Gear down need more of throttle release, transmission unloaded just between acceleration and deceleration.

Red lights worse. I was lucky with timing, not much traffic so I could ride slower until green.
When stopped, on neutral, I started on 2nd gear throttle with starter. Warm engine no problem.

The cables are details to keep an eye on.
As the 2 screws holding front sprocket. I saw in time that one was totally missing, the 2nd was close to leave the ship, halfway out.

After that Loctite 222 on those after cleaning threads with acetone.
222 also for front disc nuts, nuts on fork studs holding wheel, rear passenger bolt nuts, 4-1 exhaust rear bolt/nut, rear sprocket nuts.
« Last Edit: February 12, 2022, 08:50:36 AM by PeWe »
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline Don R

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Re: throttle cable fail at 75 mph
« Reply #8 on: February 12, 2022, 09:23:34 AM »
  I've heard of swapping the cables, you would need your tool set and a safe lighted place to work.
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Offline ekpent

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Re: throttle cable fail at 75 mph
« Reply #9 on: February 12, 2022, 10:05:41 AM »
 Smokers know the fine art of clutchless upshifts well. One hand on the throttle the other on the cig and shift away through the gears.---------

Offline evinrude7

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Re: throttle cable fail at 75 mph
« Reply #10 on: February 12, 2022, 01:31:09 PM »
i don't have a push cable on the throttle, only a pull.  i had a replacement clutch cable with me but not a throttle cable. 
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Offline ekpent

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Re: throttle cable fail at 75 mph
« Reply #11 on: February 12, 2022, 03:32:35 PM »
We will see how bad we get flamed but I have just the one cable hooked up on some of my 750's also. 8)

Offline dave500

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Re: throttle cable fail at 75 mph
« Reply #12 on: February 12, 2022, 05:23:50 PM »
last night i was heading home from the work week and my throttle cable gave up the ghost.  luckily i had a fairly clear path to the shoulder of the highway.  after an hour and a half of trying to decide if i should have the wife come with the pickup or wait for a free tow through my insurance (which after an hour they hadn't even assigned a truck) i turned the idle set screw up to 3K then 4K after i got moving and meandered the back roads home.  top speed down hill was maybe 45 but mostly i was going about 20-30 waving cars around me all the way.  the cable busted loose at the clam shell and i could not figure out a fix.  has anyone had this happen at the top of the cable and macgyvered a way to get it working again while stuck on the side of a highway?

i did the exact same thing on my tt600 not long ago,lot to be said of old tech,cant do that with injection?

Offline evinrude7

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Re: throttle cable fail at 75 mph
« Reply #13 on: February 13, 2022, 07:05:03 AM »
We will see how bad we get flamed but I have just the one cable hooked up on some of my 750's also. 8)

oh well.  everything is good until it breaks down.  i ordered a set of push/pull from DSS. 
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Offline evinrude7

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Re: throttle cable fail at 75 mph
« Reply #14 on: February 13, 2022, 07:07:10 AM »
last night i was heading home from the work week and my throttle cable gave up the ghost.  luckily i had a fairly clear path to the shoulder of the highway.  after an hour and a half of trying to decide if i should have the wife come with the pickup or wait for a free tow through my insurance (which after an hour they hadn't even assigned a truck) i turned the idle set screw up to 3K then 4K after i got moving and meandered the back roads home.  top speed down hill was maybe 45 but mostly i was going about 20-30 waving cars around me all the way.  the cable busted loose at the clam shell and i could not figure out a fix.  has anyone had this happen at the top of the cable and macgyvered a way to get it working again while stuck on the side of a highway?

i did the exact same thing on my tt600 not long ago,lot to be said of old tech,cant do that with injection?

might need a laptop with you to over ride the system with injection.   ::)
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Offline Pappy

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Re: throttle cable fail at 75 mph
« Reply #15 on: February 13, 2022, 08:25:27 AM »
Evinrude7 - Interesting name. I worked for OMC for 22 years in engineering and as a tech rep for them. Got into antique outboards and boats and have over 125 engines and around 7-8 boats.

Offline evinrude7

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Re: throttle cable fail at 75 mph
« Reply #16 on: February 14, 2022, 06:20:41 AM »
Evinrude7 - Interesting name. I worked for OMC for 22 years in engineering and as a tech rep for them. Got into antique outboards and boats and have over 125 engines and around 7-8 boats.

an old drummer of mine from years back gave me that nickname.  why i don't know. 
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Offline Stev-o

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Re: throttle cable fail at 75 mph
« Reply #17 on: February 14, 2022, 07:55:37 AM »
  has anyone had this happen at the top of the cable and macgyvered a way to get it working again while stuck on the side of a highway?

Had same issue with my Kawasaki H2 a couple years ago.  Called a buddy that lived nearby and asked him to bring some needle nose pliers. I used the pliers to pull the cable to give it it throttle, luckily I was only about 2 miles from home and rode through the neighborhood.

BTW - the cable was only a year old, they dont make 'em like they used to!
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Offline evinrude7

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Re: throttle cable fail at 75 mph
« Reply #18 on: February 14, 2022, 04:44:17 PM »
  has anyone had this happen at the top of the cable and macgyvered a way to get it working again while stuck on the side of a highway?

Had same issue with my Kawasaki H2 a couple years ago.  Called a buddy that lived nearby and asked him to bring some needle nose pliers. I used the pliers to pull the cable to give it it throttle, luckily I was only about 2 miles from home and rode through the neighborhood.

BTW - the cable was only a year old, they dont make 'em like they used to!

i thought about doing something similar.  speed limits on some of the roads were over 50 so i opted for constant motor speed. 
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Offline evinrude7

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Re: throttle cable fail at 75 mph
« Reply #19 on: March 02, 2022, 03:07:25 PM »
the two cables from DSS showed up and i installed them.  big difference in throttle control, at least to me who's been using only a pull cable for the last 5 years.  i think i have the push cable routed correctly.  went down under the right side coil.  seems good.  can anyone concur? 
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Offline HondaMan

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Re: throttle cable fail at 75 mph
« Reply #20 on: March 02, 2022, 04:52:06 PM »
Never tried this, but could you swap in the “push cable” (stupid name) and ride home twisting the grip backwards? I wonder......
Exactly I was camping in a town in the middle of Utah in 1973 when my pull cable broke as I putted toward my campsite.
I spent the next hour swapping the push cable into the pull cable's hole in the throttle linkage and limped my way 30 miles the next day to the nearest Honda shop where they had a +6" pull cable (for choppers) in stock. I rode the rest of the tour with the extra loop of cable banging around inside my Vetter every time I turned the bars, bought a new one when I got home. The OEM pull cable had lasted about 30k miles at that point. The OEM push cable lasted until 1990-something when it finally started fraying at the grip.
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Offline evinrude7

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Re: throttle cable fail at 75 mph
« Reply #21 on: March 02, 2022, 05:37:34 PM »
Never tried this, but could you swap in the “push cable” (stupid name) and ride home twisting the grip backwards? I wonder......
Exactly I was camping in a town in the middle of Utah in 1973 when my pull cable broke as I putted toward my campsite.
I spent the next hour swapping the push cable into the pull cable's hole in the throttle linkage and limped my way 30 miles the next day to the nearest Honda shop where they had a +6" pull cable (for choppers) in stock. I rode the rest of the tour with the extra loop of cable banging around inside my Vetter every time I turned the bars, bought a new one when I got home. The OEM pull cable had lasted about 30k miles at that point. The OEM push cable lasted until 1990-something when it finally started fraying at the grip.

see my reply/question above your post mark.  do i have the push cable routed correctly? 
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Offline HondaMan

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Re: throttle cable fail at 75 mph
« Reply #22 on: March 03, 2022, 06:09:55 PM »
Never tried this, but could you swap in the “push cable” (stupid name) and ride home twisting the grip backwards? I wonder......
Exactly I was camping in a town in the middle of Utah in 1973 when my pull cable broke as I putted toward my campsite.
I spent the next hour swapping the push cable into the pull cable's hole in the throttle linkage and limped my way 30 miles the next day to the nearest Honda shop where they had a +6" pull cable (for choppers) in stock. I rode the rest of the tour with the extra loop of cable banging around inside my Vetter every time I turned the bars, bought a new one when I got home. The OEM pull cable had lasted about 30k miles at that point. The OEM push cable lasted until 1990-something when it finally started fraying at the grip.

see my reply/question above your post mark.  do i have the push cable routed correctly? 

It might be: take a look at page Appendix E-4 in my book, there's a shot there where the cables can be seen correctly routed.
In the K6 bikes after the F0 bike came out, the ends of the push cable had longer ends on them, which forced the cable to have to descend more. I think this may be where some of the confusion comes from, because the F0 bikes' cable change was used on those K6 bikes when Honda hurriedly started [re]making the K again. With those longer cable ends the push cable has to go thru the frame triangle by the coils and then down a little or else the bend at the end tries to kink the cable and make it drag.
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

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Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
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Offline evinrude7

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Re: throttle cable fail at 75 mph
« Reply #23 on: March 04, 2022, 04:52:21 AM »
Never tried this, but could you swap in the “push cable” (stupid name) and ride home twisting the grip backwards? I wonder......
Exactly I was camping in a town in the middle of Utah in 1973 when my pull cable broke as I putted toward my campsite.
I spent the next hour swapping the push cable into the pull cable's hole in the throttle linkage and limped my way 30 miles the next day to the nearest Honda shop where they had a +6" pull cable (for choppers) in stock. I rode the rest of the tour with the extra loop of cable banging around inside my Vetter every time I turned the bars, bought a new one when I got home. The OEM pull cable had lasted about 30k miles at that point. The OEM push cable lasted until 1990-something when it finally started fraying at the grip.

see my reply/question above your post mark.  do i have the push cable routed correctly? 

It might be: take a look at page Appendix E-4 in my book, there's a shot there where the cables can be seen correctly routed.
In the K6 bikes after the F0 bike came out, the ends of the push cable had longer ends on them, which forced the cable to have to descend more. I think this may be where some of the confusion comes from, because the F0 bikes' cable change was used on those K6 bikes when Honda hurriedly started [re]making the K again. With those longer cable ends the push cable has to go thru the frame triangle by the coils and then down a little or else the bend at the end tries to kink the cable and make it drag.

yes there is a bit of bend out of the triangle to go downward.  no drag yet. 
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