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-   -   Does 1mm really matter? (https://www.bikeforums.net/showthread.php?t=1266693)

Albion 01-24-23 05:21 PM

Does 1mm really matter?
 
Hi fellow C&V viewers, I am refurbishing my lovely old '74 Araya and have a couple of questions for which any input would be gratefully received:
  • The front derailleur seems to be impossible to adjust correctly, including throwing the chain, so I am looking at replacing both front and rear with the most appropriate NOS I can find (non-indexed, rear "hook"). Before writing, I checked the chainrings for any bends, horizontal alignment of the rear derailleur using a hexagonal rod in the pivot, usual alignment checks, also had a friend with more experience than I check and ride but changing the front chainring still sees the chain come off. Any thoughts on what I should look for with a semi-decent chance of success in finding that represents the art for a 1970s - 1980s machine?
  • I'll also be replacing the 48 year old brake and shifter cables with Jagwire. But I can't locate 4mm cable end ferrules for the shifter runs. I have seen "5mm to 4mm" but this seems to be a bit of a cop out. Any thoughts where brass 4mm shift cable ferrules can be bought? I am aware that I can buy black nylon ones from Jagwire that are twice the length and maybe even anodized aluminum parts in garish colors but they just offend the eye and I would prefer to retain a semblance of originality.
As always, many thanks in advance for your advice - it's always most welcome.

https://cimg8.ibsrv.net/gimg/bikefor...ab583345fb.jpg
Has this front derailleur had it?
https://cimg0.ibsrv.net/gimg/bikefor...e3d9382cc2.jpg
Or the rear one?
https://cimg7.ibsrv.net/gimg/bikefor...b8ba9646fc.jpg
Really?

icemilkcoffee 01-24-23 05:41 PM

4mm cable end caps:
https://www.ebay.com/itm/122884424525
(you have to select either 4mm or 5mm with the drop down box)

Albion 01-24-23 05:52 PM

Thank you!
 
Hi Icemilkcoffee, thank you so much! I immediately ordered a couple of packets. And this was after an extended search, using all the search term variations I could think of - but still didn't find them. For others like me, here's what he directed me to:


https://cimg5.ibsrv.net/gimg/bikefor...fa52d6336f.jpg

ehcoplex 01-24-23 05:55 PM

I don't think you should give up on those Suntour mechs yet- they're pretty bulletproof and shouldn't be giving you so much trouble. That FD is 'high normal', which means the spring want's to pull it to the large ring- you know that, right? (sorry, no intention of being condescending- just checking) Are you losing the chain to the inside, when shifting from big to small, or to the outside when going from small to big ring? Give us some more info, maybe we can collectively get you sorted out!

panzerwagon 01-24-23 06:07 PM

FD passes at least the eye test. Random ideas:
- From the marks on the seat-tube, it appears to have been installed differently in the past. Are you sure installation is correct? (a) clearance directly above big ring, (b) cage angle.
- Lubricate all derailleur hinges (check movement by hand once cables are disconnected).
- Incorrect or worn chain?

Good luck, love those components.

alcjphil 01-24-23 06:13 PM


Originally Posted by Albion (Post 22779826)

From the angle of this photo it is difficult to tell if the derailleur is too high above the large chainring. I think it might be. A photo taken at the same level as the derailleur might show this better

52telecaster 01-24-23 06:17 PM

I would also say the suntour mech is good stuff.

Albion 01-24-23 06:28 PM

Hi Echoplex, I really appreciate your input. The chain tends to come off more usually when moving to the larger front chainring with the chain dropping onto the crank arm (urgh). There is one difference I have noted, compared with my '80 Fuji, and it's the rear derailleur tension - when rotating the cage plate near the idler pulley the twisting force required is about half (I have just ordered a spring scale to check more exactly). Might there simply not be enough tension in the chain to keep it seated on the front chainring? If so, it's within my ability to take the rear changer apart and increase the tension by half a turn (say).

CroMo Mike 01-24-23 07:55 PM

I'm not familiar with that front derailleur but it looks like the linkage is out of sorts.

ehcoplex 01-24-23 08:03 PM


Originally Posted by Albion (Post 22779908)
Hi Echoplex, I really appreciate your input. The chain tends to come off more usually when moving to the larger front chainring with the chain dropping onto the crank arm (urgh). There is one difference I have noted, compared with my '80 Fuji, and it's the rear derailleur tension - when rotating the cage plate near the idler pulley the twisting force required is about half (I have just ordered a spring scale to check more exactly). Might there simply not be enough tension in the chain to keep it seated on the front chainring? If so, it's within my ability to take the rear changer apart and increase the tension by half a turn (say).

Hmm, could be. But could be a number of other things, too. Old/worn chain can cause issues, too. This past summer I had a heck of a time getting the Simplex FD on my Pug to shift well and to not drop the chain (granted, I'm using an FD designed for a double on a triple..)- in the end bending the front edge of the FD's outer cage inward just a little bit, and doing a lot of fine tuning of the limit screw and I finally got it shifting great. Do you have a bike stand? I think that's probably essential- trying to get derailleurs properly adjusted without one is seriously frustrating!

ehcoplex 01-25-23 07:54 AM

I think the V-Compe FD is actually alloy body with a steel cage. Maybe not high-end, but decently regarded- though the high-normal takes getting used to, and some folks don't like it. Albion , you might want to start a new thread specifically to get the FD issue sorted out- there's tremendous knowledge here, but this thread title may not get the eyeballs you need to solve this. Also, a straight on photo of the FD & crankset (and also of the whole drivetrain) might be helpful. I think it takes quite a lot of use/abuse to render old Suntour mechs unusable- I'd be really surprised if, with some effort, you can't get this one working properly.

Mr. 66 01-25-23 08:15 AM

I think that fd has a cable stop. The housing is one more spot that may need lubricant.

Some of those old systems would use a lot of overhift and trim back into place. The last times I've had those cranks I had chain suck in between the chainrings. Nice solid rings but the spacing is more than most all, they take a lot of fd movement for shifting ups or downs.

Maohaus 01-25-23 09:04 AM

I am very interested in the Araya bicycles. Would you be willing to share some more photos and information about your Araya? Would love to know the model, frame material, which bike shop from which it came etc. Thanks, Mark

1989Pre 01-25-23 09:13 AM

Increase chain tension with "b" limiter screw on rear derailleur.

smd4 01-25-23 09:14 AM


Originally Posted by CroMo Mike (Post 22779983)
I'm not familiar with that front derailleur but it looks like the linkage is out of sorts.

How so?

Maohaus 01-25-23 09:17 AM

I should mention that it is not at all unusual or incorrect to slightly bend the inside plate of the front derailleur to assist it lifting the chain to the large chainring. If you bend it ever so slightly inward, you may be able to back off the outboard adjustment screw. We did that routinely when I was a mechanic in the shops in the early 70's and 80's.. By the way, I always use a Crescent wrench to make the gentle bend.

ehcoplex 01-25-23 10:16 AM


Originally Posted by Mr. 66 (Post 22780293)
I think that fd has a cable stop. The housing is one more spot that may need lubricant.

Yup, those high-normal FDs require a length of cable housing- it's actually the housing itself that moves the derailleur pivot. I just took a look at the Suntour SL FD I've got on my tandem and I think it's basically the same as the Compe-V, just with a different cage (alloy, different styling). Dialed in, it works really well for me.

dddd 01-25-23 04:01 PM

Great suggestions, the old front derailers thankfully have a good length of forward protrusion where the tips of the cage can be bent inward to better control a narrow chain (these were designed for use with 8mm wide chain!).

The Suntour V-GT rear derailer features adjustable cage pivot tension! One has to unscrew the stopper pin on the cage with a screwdriver, then unwind the cage enough to reposition the end of the spring one position tighter (under the big/heavy chrome cap with a 6mm hex socket in it). Then you re-secure the cap, wind the cage back up, and reinstall the stop pin (add grease while you're in there).

If you tighten the B-tension screw to effect greater chain tension, the shifting will become sadly unresponsive, and may increase the risk of throwing the chain into the spokes. Remember that these derailers were designed for laterally-stiff bushing-type chains, so the shifting response is already challenged just by using modern chain (which are much more flexible than even the bushingless Sedisport chain).

I really prefer using index-shift cable housing for ALL rear derailer use. It really improves responsiveness, especially with friction shifters!
A supply-chain problem arises though when a 4x5mm ferrule (not 4x6mm) is needed to fit modern 4mm shift housing and still fit into the narrower ~5mm housing stops on old frames (and even on old stem shifters and rear derailers).
Shift cable housing really always needs to be well-captured by a ferrule, or by a deep, squared-bottom, 4mm port in the component.
But brake cable housing can be run without any ferrule if it simply fits ok in whatever stop that it rests against.

I occasionally find 4x5mm metal ferrules, my Schwinns needed them, don't know where to find more though.
A stepped ferrule is often the next-best answer, each situation is different, these differences are sadly not the best feature of old bikes!

CroMo Mike 01-25-23 08:10 PM

Originally Posted by CroMo Mike View Post
I'm not familiar with that front derailleur but it looks like the linkage is out of sorts.


Originally Posted by smd4 (Post 22780340)
How so?

It looks like the upper and lower pivot arms are out of their "bearings" in the clamping body (moved rearward) and the limit screws are therefore not contacting their spots on the pivoting part of the upper pivot arm?
Image from Velobase:
https://velobase.com/CompImages/FDer...6ADABCD87.jpeg

smd4 01-25-23 08:25 PM


Originally Posted by CroMo Mike (Post 22780986)
Originally Posted by CroMo Mike View Post
I'm not familiar with that front derailleur but it looks like the linkage is out of sorts.



It looks like the upper and lower pivot arms are out of their "bearings" in the clamping body (moved rearward) and the limit screws are therefore not contacting their spots on the pivoting part of the upper pivot arm?
Image from Velobase:
https://velobase.com/CompImages/FDer...6ADABCD87.jpeg

OK, I see what you’re saying now. That pic helped.

Yeah, it might be tweaked.

SpedFast 01-25-23 08:30 PM

Nothing wrong with your front derailleur that can be seen by the pics, just find someone to set the limiter screws correctly. They're the 2 little screws on top. I have the same setup on one of my older bikes and let me tell you, those old Suntours are bullet proof. Good luck

CroMo Mike 01-25-23 08:47 PM

Here's his derailleur. Note that the limit screws hit the shaft, not the arm.


https://cimg8.ibsrv.net/gimg/bikefor...ab583345fb.jpg

smd4 01-25-23 09:01 PM


Originally Posted by CroMo Mike (Post 22781021)
Here's his derailleur. Note that the limit screws hit the shaft, not the arm.

That could be the molded-in aluminum stop we’re seeing, in an odd light.

ehcoplex 01-25-23 09:31 PM

Yeah, I think that’s the molded in stop. Here’s a pic of the SL on one of my bikes (I think the only real dif is the cage is alloy on the SL)-

https://cimg8.ibsrv.net/gimg/bikefor...4ea85cfe6.jpeg
I suspect the mech wouldn’t function at all if the arms were slid back on the shaft..

Albion 01-26-23 02:55 PM

Araya
 

Originally Posted by Maohaus (Post 22780329)
I am very interested in the Araya bicycles. Would you be willing to share some more photos and information about your Araya? Would love to know the model, frame material, which bike shop from which it came etc. Thanks, Mark

Hi Maohaus, here's what I know about my old Araya:Araya made a short foray into complete bikes before returning to rims alone. Mine was literally pulled out of caleche (hard, Arizona clay) from a hoarder's back yard. Sadly the model name faced the sun and was on a soft, black stencil or decal and it was mostly gone when I bought the bike.

The BB shows C432754, nothing on the dropouts. Hummer advised, as part of a discussion with the learned T-Mar: “The serial number on your Araya is an Araya serial number, not Bridgestone. In 1977 Araya started to put an ‘ARY’ prefix on their serial numbers. Araya frames built prior to that had serial numbers without the prefix. The letter "C" at the start of the serial number is for the month of frame manufacture, C = March. The first digit "4" is for the year of frame manufacture, 4 = 1974.”

T-Mar also provided date information on the rear derailleur: ". . . the date code (on the RD) is QB, which represents, February 1974, which should make the frame a 1974 model."

I hope this is of interest!
https://cimg4.ibsrv.net/gimg/bikefor...439f7dc78a.jpg
Nothing special but fits like a glove . . .

https://cimg0.ibsrv.net/gimg/bikefor...5c2d6ef2f1.jpg

https://cimg9.ibsrv.net/gimg/bikefor...1aeadaa760.jpg
Basic frame work . . .


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