Clutch cable brakes often
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Vespa P200E
Joined: 07 Oct 2016
Posts: 7
Location: Québec city
Tue Jun 11, 2019 11:20 am quote
Hello.
I have a question to ask to vintage scooterists.
I've been driving a 1981 Vespa P200E for the last 14 years and make about 3000 km per summer, in 6 months.
I drive mostly in the city.
For many years, I had to change the clutch cable 2 or 3 times a year.
It breaks at the clutch actuating arm.
I joined a picture but it's not my scooter. Mine is cleaner !
I looked today and it's breaking again.
I thought that the hole in the arm, where the cable goes through, was too sharp so I filed it a little bit. But the cable still breaks.
Is this something that happens to other scooterists ?
What should I do about it ?
Some people add an extra piece of outer cable between the pinch bolt and the arm. It might help.
Thanks for your help.

clutch actuating arm.jpg

Hooked
2013 Vespa GTS300 Super, 2005 Vespa GT200, 2003 Stella, 1980 Vespa P200E
Joined: 15 Jun 2011
Posts: 268
Location: Jacksonville, Florida
Tue Jun 11, 2019 11:49 am quote
I have a P200 (I've owned since 1981) and a 2003 Stella (I've owned since 2004). Have put about 43,000 combined miles them. In all this time, I've broken maybe 5-6 cables on the combined bikes. Every other time I change the inner cable I also change the outer cover. You may have a rough spot inside the outer that's causing the inner to break. Change both next time and see if that helps get longer cable life.
Member
Vespa P200E
Joined: 07 Oct 2016
Posts: 7
Location: Québec city
Tue Jun 11, 2019 12:00 pm quote
It's a good idea but the cable breaks near the actuatuing arm.
Hooked
2013 Vespa GTS300 Super, 2005 Vespa GT200, 2003 Stella, 1980 Vespa P200E
Joined: 15 Jun 2011
Posts: 268
Location: Jacksonville, Florida
Tue Jun 11, 2019 12:04 pm quote
1) Something's gotta be rubbing on the cable to not last longer, or
2) Cheap cables, or
3) Bad luck
Ossessionato
Joined: 22 Oct 2011
Posts: 3827
Location: Tega Cay, SC
Tue Jun 11, 2019 3:49 pm quote
If you are missing the little copper bits that go on both sides of the cable as it goes thru the barrel clamp, the the tightening screw will chew it up as you tighten it, causing an earlier demise.
Veni, Vidi, Posti
MP3 500, GTS 250 (both 2008 MY), 2010 Can Am Spyder RT-S, 2012 Honda NC700 DCT
Joined: 02 Mar 2013
Posts: 5129
Location: Madison, Wisconsin
Tue Jun 11, 2019 4:47 pm quote
Looks to me two things are possible.
1. Overtightening the clamp on the cable. Causes the strands to get bent too hard and sort of twist when pulled on.
2. Related to 1, but when the clutch is pulled in, the cable pulls the moving bit toward the housing (duh), which causes some bending at the clamp. Bending a previously over-bent bit of wire will cause it to break.

This may be too big, but here's an idea:

https://www.amazon.com/Dorman-03339-Cable-Stop/dp/B000COCQ06/ref=pd_bxgy_263_3/147-1944302-3437430?_encoding=UTF8&pd_rd_i=B000COCQ06&pd_rd_r=834d7b36-8cab-11e9-8ce9-f1e62de2a0f4&pd_rd_w=GUsxe&pd_rd_wg=iKYkY&pf_rd_p=a2006322-0bc0-4db9-a08e-d168c18ce6f0&pf_rd_r=NYRVVXG03RX0PJE7ZACJ&psc=1&refRID=NYRVVXG03RX0PJE7ZACJ
Hooked
GTS300, GTV300, 71Rally 180, 64VBB, 79&80 P200
Joined: 05 Jan 2009
Posts: 133
Location: North West Georgia
Tue Jun 11, 2019 4:52 pm quote
Tierney wrote:
If you are missing the little copper bits that go on both sides of the cable as it goes thru the barrel clamp, the the tightening screw will chew it up as you tighten it, causing an earlier demise.
+1
Member
Vespa P200E
Joined: 07 Oct 2016
Posts: 7
Location: Québec city
Wed Jun 12, 2019 8:33 am quote
Thanks for your answers.

I think I probably tighten the nut on the clamp too much.
But how much is enough or too much ??

I'll check if the little copper bits that go on both sides of the cable as it goes thru the barrel clamp are there. I know it's important.

I will also add a little piece of outer cable between the pinch bolt and the arm so that if the nut is too tight it won't bend and break the cable there when I pull the clutch lever.

Last edited by Bernard69 on Wed Jun 12, 2019 9:15 am; edited 1 time in total
Molto Verboso
08 GTS 250, 79 P200E, 62 Allstate
Joined: 11 Jan 2006
Posts: 1044
Location: Florence, OR
Wed Jun 12, 2019 9:03 am quote
Hey Bernard,

You might also want to take a little dinky small round file to the inside of the clutch arm. It might have a little burr that is working on the cable also...

Always good to keep a couple of spare pinch bolts around.
Member
Vespa P200E
Joined: 07 Oct 2016
Posts: 7
Location: Québec city
Wed Jun 12, 2019 9:14 am quote
Thanks for the advices gascooter !!
Ossessionato
LXV 150 Midnight Blue (SOLD)
Joined: 06 Dec 2010
Posts: 2605
Location: Bangkok
Wed Jun 12, 2019 4:55 pm quote
some m/bike cable clamps have a spigot.



Or dry install the next cable and solder it where it passes through the arm and the clamp before greasing.
Member
Vespa P200E
Joined: 07 Oct 2016
Posts: 7
Location: Québec city
Wed Jun 12, 2019 5:23 pm quote
I should try to find a clamp like this. It would help.
Thanks.
Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 1200
Location: London UK
Wed Jun 12, 2019 6:58 pm quote
The position of the clutch arm at rest, depends on the condition of the actuator components inside. These do wear heavily and cause the rest position of the arm to move forward. When the rest position of the arm gets too far forward the angle of the pulled in clutch is such that the cable keeps breaking.
I suspect this is what your real issue is.
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 6836
Location: Victoria, Australia
Wed Jun 12, 2019 7:15 pm quote
With the extra outer cable, it allows the cable to maintain direction (ie not bending) through the eye of the lever to a degree. This partially takes the stress off the cable at that point. I found mine were breaking at the nipple which is why I came up with the idea. If you do break it you have the opportunity to simply cut it a bit shorter without replacing it.

https://scooterlab.uk/scooterist-tip-5-large-frame-vespa-clutch-cable-workshop/
Ossessionato
LXV 150 Midnight Blue (SOLD)
Joined: 06 Dec 2010
Posts: 2605
Location: Bangkok
Wed Jun 12, 2019 8:06 pm quote
Ginch wrote:
With the extra outer cable, it allows the cable to maintain direction (ie not bending) through the eye of the lever to a degree. This partially takes the stress off the cable at that point. I found mine were breaking at the nipple which is why I came up with the idea. If you do break it you have the opportunity to simply cut it a bit shorter without replacing it.

https://scooterlab.uk/scooterist-tip-5-large-frame-vespa-clutch-cable-workshop/
This look good. I was thinking reverse cable like the Lambretta front brake but I'm not sure there is enough room under there.
The extra outer bit is close.
Banned
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Location: San Francisco
Molto Verboso
2005 PX150 In a Love-Hate Relationship with a 2-Stroke Vespa Since 2007
Joined: 01 Sep 2007
Posts: 1791

Thu Jun 13, 2019 7:54 am quote
qascooter wrote:
Hey Bernard,

You might also want to take a little dinky small round file to the inside of the clutch arm. It might have a little burr that is working on the cable also...

I was going to say this. The clutch arm is cast. I’d take off the cover and have a very close look inside the hole in the arm where the cable passes. It might just possibly have a rough spot in there.

The other possibility is the pinch bolt insert as others have mentioned. I’m only aware of there being one of them that keeps the bolt from directly contacting the cable. They’re easy to lose if you completely remove the bolt from the barrel.
Addicted
'64 Motovespa 150S (177) , '76 V90 ( 133)
Joined: 27 Mar 2013
Posts: 538
Location: S.Salem, NY
Thu Jun 13, 2019 7:58 am quote
usmusket wrote:
Tierney wrote:
If you are missing the little copper bits that go on both sides of the cable as it goes thru the barrel clamp, the the tightening screw will chew it up as you tighten it, causing an earlier demise.
+1
+2
Veni, Vidi, Posti
a herd of easy shifty rats
Joined: 22 Nov 2010
Posts: 6775
Location: seattle/athens
Thu Jun 13, 2019 1:46 pm quote

One of the problems here is that the pinch bolt is horizontal and doesn't pivot when you clutch, flexing the able a tiny bit on every shift. Try to keep it vertical or use Ginch's trick. I use it & I like to grind the contact end of added cable outer into a ball shape so it can seat on the clutch lever how it likes. Grease the contact area.
Moto64 wrote:
usmusket wrote:
Tierney wrote:
If you are missing the little copper bits that go on both sides of the cable as it goes thru the barrel clamp, the the tightening screw will chew it up as you tighten it, causing an earlier demise.
+1
+2
Barrel clamp or pinch bolt, same thing, right? But I always thought there was only one puck or slug inside that clamps against the cable & was taught to always loosen the 7mm a ways from the 8mm and tap the whole thing down on the 7mm head to seat the puck against the screw with the cable under it and clamped against the body of the barrel.

So I opened an old one(presumably Pisaggio) and found only one and that it is steel(magnet), probably mild steel by the looks of the cable imprint. Also, looks like this one was used twice. I have used short slugs of heavy copper wire when I had to, maybe you'e seen one similar.

pinc h.jpg

Hooked
BV 350
Joined: 22 Nov 2016
Posts: 272
Location: Nebraska
Thu Jun 13, 2019 5:11 pm quote
Bad design
Should be designed like a clutch handlebar lever, where the cable goes through a barrel that pivots (rotates) in the lever, so the cable isn't being bent each time it is actuated. Hard to tell from the picture, but either the cable is being bent at the clamp every time the clutch is actuated, or being cut by the edge of the arm. The precise location of the breakage should tell you which.

Ideally the arm should have a round shape around the barrel, allowing it to rotate so the cable does not bend, and a slot for the cable pass-through, so the cable, except for incidental side contact, never touches the arm.

Looks like a good opportunity for an aftermarket replacement.
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 6836
Location: Victoria, Australia
Fri Jun 14, 2019 4:29 pm quote
oopsclunkthud wrote:
Sharp edges where the cable passes through and flexing are the things that kill cables. I deburr the cable adjusters, tophats, levers...

Also the clutch arm on the largeframes (other than the GS/SS) does not let the cable clap hold the cable straight. This flexes the cable each time you pull the clutch. The following modification to the arm will keep things happy for a good long time.




Banned
2:6
Joined: 11 Jan 2007
Posts: 7380
Location: San Francisco
Sat Jun 15, 2019 8:18 am quote
been thinking that the arm modification could be improved a bit more with a cable clamp that closed like a collet. Was thinking I'd make some, but did a search for such a thing this morning. found them in 1/16 and 3/64th, may still have to make my own...

Release Cable MD-16008.jpg

Veni, Vidi, Posti
a herd of easy shifty rats
Joined: 22 Nov 2010
Posts: 6775
Location: seattle/athens
Sat Jun 15, 2019 9:02 am quote
I like
Don't stop there, mount it through a hardened ball* or even better a gimbal


https://youtu.be/rpHYBz7ToII
*you reminded me of this guy and his home made EDM
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 6836
Location: Victoria, Australia
Sun Jun 16, 2019 1:50 am quote
Re: I like
V oodoo wrote:
... or even better a gimbal
How about this type? I was thinking you'd cut the eye part off and use it, but it would be even nicer if it could be threaded on to the lever itself. Even the biggest ones in this list are only $6. https://tinyurl.com/y2gcja59


Veni, Vidi, Posti
a herd of easy shifty rats
Joined: 22 Nov 2010
Posts: 6775
Location: seattle/athens
Sun Jun 16, 2019 4:22 am quote

Ginch's idea FTW! Even better and you could have zero slop and zero flex.

But we'll need to make something like this to connect the standard pinch bolt & cable. I wonder if ABS plastic would work for more than a short while. Off to find an old shift arm to trim and thread the shank...

Image3.jpg

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