Somehow getting cable-stop away from the frame
 

hello -

i received some advice on this forum a couple of years ago about replacing the very hard-to-find Peugeot front deraileur with a simplex deraileur. the old Peugeot front derailer had something of a "built-in" cable-stop.

as you can see in this picture (SORRY IT APPEARS I CANNOT ATTACH A PICTURE YET), the derailleur cable is really being pulled at something like a 30-degree angle. all the cable-stops i have found assume the derailer cable arm is very close to the frame, which in this situation is nowhere close. this actually works, sort of. but i don't like the idea of a cable being pulled like that.

is there some way to somehow get the cable-stop a bit further away from the frame, like maybe at least an inch? i was tempted to try to fabricate something myself, but stuff like that never seems to turn out well for me.

the picture is where the cable-stop is really right against the frame, and the cable is pulled at a 30-degree angle. is there any way i can get special clearance to post the picture? it would be a lot easier to explain it that way.

is there interference with the frame & cable?

no interference, but i figure pulling at a 30-degree angle is adding unnecessary friction, and also wearing out the cable-housing end and probably the cable itself.

if i could email a picture to somebody with higher privilege, they could post the picture here?

thank you all. if there was some way to have the cable-stop an inch or so away from the bike frame, then the cable would not be at such an angle.

https://cimg3.ibsrv.net/gimg/bikefor...06ae60f90a.jpg

i'm not sure of a product to be effective at achieving your goal, but imo, the typical amount of use for a front der is most likely low. To which, it wouldn't warrant a smoother transition. It will have a shorter cable life, but again, small fish per the amount it is likely used.

It appears that the cable housing is routed under the bottom bracket and a the cable (housing) stop is attached to the seat tube.

Most road bikes have a cable (housing) stop at the head tube or down tube, for older down tube shifter bikes. The bare cable(s) is routed under the bottom bracket using a cable guide. The angle is probable a less severe angle coming from just behind the bottom bracket.

You fix is to mount a guide to the bottom bracket shell to route the bare cable. I think there are older clamp-on guides that accomplish the same thing.

If by chance the cable is coming down from the top tube and the housing is looped to work with a bottom pull FD, you should change the FD.

John

In addition to the strange cable stop problem, the cable is not attached correctly to the derailleur:


https://cimg0.ibsrv.net/gimg/bikefor...c1db05fd54.png

Here are the Shimano instructions, note the position of the cable:


https://cimg7.ibsrv.net/gimg/bikefor...8040e02357.png

As others have mentioned above, the ideal fix (if possible) is to replace that cable stop with a cable guide that mounts on the bottom bracket:

Shimano Bottom Bracket Cable Guide SM-SP17

I have one of these mounted on my bottom bracket, held in place only by cyanoacrylate glue (carbon frame). Works fine.

this is a VERY INTERESTING idea to use the "Shimano-Bottom-Bracket-Cable" - thank you so much for the suggestion. what would happen with the cable housing? is there a cable-stop on the "Shimano-Bottom-Bracket-Cable" ?

i had to look at an installation video to determine it goes underneath the crank, but i guess i should have known that.


https://cimg3.ibsrv.net/gimg/bikefor...7bab63622b.jpg
https://cimg4.ibsrv.net/gimg/bikefor...d3a83923f2.jpg
https://cimg5.ibsrv.net/gimg/bikefor...5799aa88cb.jpg
https://cimg6.ibsrv.net/gimg/bikefor...8f64f3a201.jpg

Okay, that's definitely the wrong cable guide for your seat tube and the wrong front derailleur as well.

The short-term solution is to move the cable guide way down the seat tube close to or directly on top of the bottom bracket shell, so that angle to the front derailleur isn't as steep. You will need to trim the housing to fit.

The long-term solution is to find a front derailleur with a housing stop like those that Suntour is known for. Then you can remove that ridiculous cable guide from the seat tube altogether.

yes, that is what i was wondering in my original question, and i have yet to find a front derailer that attaches to the frame AND has a built-in cable stop. when i look for Suntour, all i see is front derailers on ebay.

huh, at the time i did this, i thought it was rather ingenious of me. 😅

thank you so much surferRosa - i take it there is no way to find a new one? they are all used on eBay?

You can also get clamp on cable guides that fit just above the bottom bracket.

No need for the cable housing. You will need a cable stop near the rear derailleur, and probably on top of the chainstay.

https://www.ebay.com/itm/255463602766

Several brands should have made them.

Because new is almost always better than used? I always try to replace my stuff with NOS if I can; some stuff is used, but is impossible to tell. That works too.

If the kickstand doesn’t completely block that space, you could just run a bit of cable housing from that housing stop on the lower downtube and under the BB and just long enough to keep the cable from rubbing the BB. Then the cable can run free and straight up to the current derailleur attachment. But there may not be room.

Otto

Less wear? Better finish? I'd personally prefer to put the wear and scratches on the derailleur myself. My bike is "vintage," but I still try to replace parts with new when I can.

However, I get that having a nice looking, clean, well-maintained bike isn't for everyone.

Not sure I "advised" him to do anything. Just said what I'd so. I saw the pics. But he could begin to make his bike into a showpiece starting with a new FD! :p

I don't remember if I've seen your bikes, but the way you say that, not sure if I want to...Do they look like crap?

They're nice. Like I said, even thought I've got some used parts on my bike, like yours, you'd never know.

bought that one you recommended and installed it.... 😁 i pretty much "destroyed" the old front derailer rather than break the chain again, even though i have the tool. i should ask why Shimano designs derailers like that, but save that one for another post.

for the record, i still like my idea (yes i am stubborn) i might send the old parts to a machine-shop guy and let him come up with a cable stop that is "offset" for Shimano.

and next up, to remove a pedal and take it into an REI store, see about clip-in shoes/pedals, and hopefully without having to redo the pedal threads.

EDIT: bought the one that SurferRosa found, not necessarily recommending that specific one. but it does seem to work. still, it seems a bit odd that the only derailleurs that work are used and i cannot somehow get a new Shimano to work for me. it will be interesting to see if the machine shop guy has any ideas.

You shouldn't have to redo the threads. Assuming you remove the pedal correctly.

somebody warned me it might not be that easy on an old Peugeot bicycle. i do remember being told a long time ago that European bicycle manufacturers were extremely nationalistic on their thread sizes.

I'm not really a bike mechanic, but that looks like something somebody kludged together until it was "good enough."

Older French bikes may have metric pedal thread, but starting around 1980, English/ISO thread was used. Often, pedal thread spec is marked on the crank arm. If you can't find metric thread pedals, the arms can be re-tapped to English/ISO thread.

^^^^
Plus +1

apparently, that was 1978 or earlier! i just tried screwing in a new mountain-bike LEFT pedal and the threads match. :love: