Problems with down-tube shifters

[531colin]

Possibly a 7 spd shifter? My set up is 7spd shifter, 8 spd cassette, 9/10 spd rear mech which somehow works. I think the 7 spd shifter shifts more cable per click so the 9/10spd rear mech moves more than it would normally but this matches the 8spd cassette spacing.

Except that there is no such thing as a 9/10 speed mech., thats exactly what I would expect with Shimano.
Apart from some exotica, 7,8 and 9 speed rear mechs. have the same cable pull, so you can mix levers and mechs.
It wasn't until 10 speed that Shimano "improved" it all so that you couldn't mix them up.
.....and many or most 7 sp shifters have an extra click or an extra bit of travel which suits 8 speed.
7 and 8 sp. cassettes have spacing which is close enough to the same to be interchangeable in use.

My mistake, RD6500 mech is 9 spd. I seem to remember about 4% spacing difference (5mm to 4.8mm) between 7 and 8 spd cassette so you dont notice if it is set up correctly in the middle of the cassette. I assume a 9spd cassette would be incompatible at 4.35mm spacing?

Yes, I wouldn't expect to be able to mix 9 speed with 7& 8 speed.....but I haven't tried! **

Also note slowster's comments on 10 speed road/MTB mechs.....slowster's ability to marshal information is far better than mine!

** the largest number of sprockets i have tried so far is 9. however, the rest of my bikes are 8 speed, so the 9 speed bike has to put up with an 8 speed chain, simply so I don't have to carry more spares.....and it works perfectly well, with friction front shifting.
Some contributors here are surprised by that.

[interestedcp]

Except that there is no such thing as a 9/10 speed mech., thats exactly what I would expect with Shimano.
Apart from some exotica, 7,8 and 9 speed rear mechs. have the same cable pull, so you can mix levers and mechs.
It wasn't until 10 speed that Shimano "improved" it all so that you couldn't mix them up.

The "secret" Shimano 105 RD-5701 is a 8/9/10 rear mech, since it uses the same cable pull as the Shimano 9 spd. RD's. It doesn't work with any current Shimano 10 spd. shifters, or any 10 spd. shifter released after 2015, since they all use the "new" 10 spd cable pull.

It is a very good RD, been using them for years on my 9 spd. bikes. I have bought a couple for spares, since Shimano is likely to remove it from the market soon when Sora goes 10 spd., leaving only Acera/Claris quality RD's for 9 spd. shifters.

[ChrisF]

the rear mech is a Deore XT, maybe not compatible with the DuraAce shifter?

......
Shimano 10 speed MTB rear derailleurs use a different cable pull ratio and are only compatible with 10 speed MTB shifters.
.......

Aah! So that would be the problem, thanks.
Lots of options in your post.
I wouldn't mind having only an 8-speed system, but I don't really want to go changing the rear mech and/or cassette. OTOH I don't mind losing the indexing, but....

The shifters were fine and shifted all the through the 10 gears, but keeping the chain on a particular gear was a problem: it would skip and try to shift. In other words, getting 10-speed friction shifting to be spot on was an issue.

...so if that does turn out to be a problem for me as well, can I just change the cassette to an 8-speed, without changing the rear mech? Maybe this one https://www.sjscycles.co.uk/cassettes/s ... tte-1134t/

[slowster]

If you replace the 10 speed cassette with an 8 speed one:

a. You might have issues with the chain, depending upon what speed chain you choose. I suspect that the extra width of an 8 speed chain might not suit a 10 speed rear derailleur, although you might be able to use washers to increase the space between the jockey arm plates to address that.

An 8 speed chain will not in my experience work well with a 10 speed front derailleur - the extra width means the chain will be very prone to rubbing on the inside of the cage in many gears, and you would probably find yourself continually making fine adjustments with the DT lever to stop the rubbing after making a rear shift.

My guess is that a 10 speed chain would be too narrow for an 8 speed cassette, and I suspect that might also apply to a 9 speed chain.

b. If you are considering that 11-34 8 speed cassette because you currently have an 11-34 10 speed cassette, I think you are likely to be disappointed. The big benefit in my opinion of the 10 speed cassette is the 2 tooth gaps in the middle of the cassette. The 8 speed cassette has 3 tooth gaps starting from the 15t sprocket. For many people, including me, those 3 tooth gaps are too large for comfort.

I suspect Bice's problems with 10 speed friction shifting are to a significant degree down to:

i. A ladies' frame which is probably more flexible than your Galaxy, i.e. 'pull-back' will be much worse,

ii. Use of a rear derailleur with a much smaller cable pull ratio than your mech.

iii. A Suntour Powershift lever with a small barrel of a size suitable for 6 speed, not 10 speed.

Your 10 speed XT derailleur requires 3.4mm of cable pulled to move the arm the distance required between two sprockets on a 10 speed cassette. In contrast a 10 speed road rear derailleur requires only 2.3mm, a 9 speed derailleur only 2.5mm and an 8 speed mech 2.8mm.

In other words, a 10 speed MTB rear derailleur will be much more tolerant of the set up being less than perfect and of any cable movement. It just needs a shifter that has the capacity to pull 3.4mm x 9 = 30.6mm. The Dia Compe friction shifter I linked to has that and a longer lever as well to suit.

That all said, I doubt that you have supplied all relevant/correct information. If you have 10 speed down tube levers and a 10 speed MTB rear mech, your levers should not pull enough cable to change from smallest to largest sprocket, whereas you state that the lever pulls enough cable to move from smallest to largest in 7 clicks.

[ChrisF]

......
........
........ That all said, I doubt that you have supplied all relevant/correct information. If you have 10 speed down tube levers and a 10 speed MTB rear mech, your levers should not pull enough cable to change from smallest to largest sprocket, whereas you state that the lever pulls enough cable to move from smallest to largest in 7 clicks.

Well, I was beginning to think you'd solved it, and to go for the recommened shifters, but your last paragraph has really confused things! I understand what you mean here - but also I'm quite certain I've given all the relevant facts - what might I be missing? All that's left is the possiblity that the shifter itself is faulty, or I have assembled it incorrectly. I found an exploded diagram (on Ebay!) and it looks correct.

Anyway, if a friction shifter such as the Dia Compe one you recommend should solve it, I'm willing to give it a try (albeit at £80!) - as I mentioned ealier, the original shifters weren't indexed.

[slowster]

If it is not the shifter, that largely only leaves the rear derailleur. I suggest you provide photographs of it, viewed both side on and from the rear.

[531colin]

How downtube levers are fitted viewtopic.php?t=57027&hilit=skinflints....from something long ago!

If you have taken apart the actual bit that does the clicks, I can't help you with that!

[Bice]

If you replace the 10 speed cassette with an 8 speed one:

a. You might have issues with the chain, depending upon what speed chain you choose. I suspect that the extra width of an 8 speed chain might not suit a 10 speed rear derailleur, although you might be able to use washers to increase the space between the jockey arm plates to address that.

An 8 speed chain will not in my experience work well with a 10 speed front derailleur - the extra width means the chain will be very prone to rubbing on the inside of the cage in many gears, and you would probably find yourself continually making fine adjustments with the DT lever to stop the rubbing after making a rear shift.

My guess is that a 10 speed chain would be too narrow for an 8 speed cassette, and I suspect that might also apply to a 9 speed chain.

b. If you are considering that 11-34 8 speed cassette because you currently have an 11-34 10 speed cassette, I think you are likely to be disappointed. The big benefit in my opinion of the 10 speed cassette is the 2 tooth gaps in the middle of the cassette. The 8 speed cassette has 3 tooth gaps starting from the 15t sprocket. For many people, including me, those 3 tooth gaps are too large for comfort.

I suspect Bice's problems with 10 speed friction shifting are to a significant degree down to:

i. A ladies' frame which is probably more flexible than your Galaxy, i.e. 'pull-back' will be much worse,

ii. Use of a rear derailleur with a much smaller cable pull ratio than your mech.

iii. A Suntour Powershift lever with a small barrel of a size suitable for 6 speed, not 10 speed.

Your 10 speed XT derailleur requires 3.4mm of cable pulled to move the arm the distance required between two sprockets on a 10 speed cassette. In contrast a 10 speed road rear derailleur requires only 2.3mm, a 9 speed derailleur only 2.5mm and an 8 speed mech 2.8mm.

In other words, a 10 speed MTB rear derailleur will be much more tolerant of the set up being less than perfect and of any cable movement. It just needs a shifter that has the capacity to pull 3.4mm x 9 = 30.6mm. The Dia Compe friction shifter I linked to has that and a longer lever as well to suit.

That all said, I doubt that you have supplied all relevant/correct information. If you have 10 speed down tube levers and a 10 speed MTB rear mech, your levers should not pull enough cable to change from smallest to largest sprocket, whereas you state that the lever pulls enough cable to move from smallest to largest in 7 clicks.

I described the Diamant ladies' frame build and the 10-speed v 8-speed here: viewtopic.php?p=1705713#p1705713

(I did use a 10-speed and then an 8-speed chain.)

I have found no problem with shifting an 8-speed chain with a 10-speed Ultegra FD-6503 front derailer, but because of a braze-on on this bike, the shifter is set far higher than I would normally do: Peetee reported that it would work fine and has same sort of set-up, and so it does. Perhaps setting it higher may help accommodate an 8-speed chain, but it just hasn't been an issue.

On the rear, for both the 10-speed experiment and the current 8-speed success, I am using an Acera X which came off a 1990s 7-speed MTB. (The bike is in the attic for the winter and I can't read the part number.)

As I explained, the Suntour ratcheted downtube shifters had no issue shifting up and down a 10-speed block, and are fine with 8-speed; they shift the front derailer fine as well.

I toured with this set up over 300 miles in the summer with no issues: I was with my club, all on light road bikes through Hants, Dorset, Wilts, so I was shifting a lot in order to keep up and I was carrying 14kgs in the panniers (far more than the others).

I have no idea what would be the cable pull on the Acera to shift from one gear to another: the joy about friction downtube shifters is that you do not need to worry about any of that. Just be sure the levers pull enough cable to get you all the way from the smallest up to the biggest cog on the block.

I, too, would expect the Diamant ladies frame to flex a bit, so there may be 'pull-back', although it feels solid compared with an ultra lightweight steel road bike.

Quite a few people who have used friction downtube shifters on 10-speed have not got on with them, as they do require precision.

[fastpedaller]

I've not read all the detail above, so forgive me if what I'm going to say has already been said or is irrelevant/redundant.
I was using indexed shifters on the 'friction' setting but the friction (despite all available adjustments) would slip if I was out of the saddle - this was definitely lever slippage, and not due to frame flex. With the lever in the indexed mode it works fine. If the OP is using indexed levers in friction mode this may be the issue - from my experience the 'frection' isn't the same as old-fashioned friction levers, and indeed ratchet levers (I think someone suggested those?) may be the solution.

[slowster]

For the record, my experience of pull-back was with Simplex Retrofriction levers and a Shimano 600EX front derailleur on a 531ST Raleigh frame. I tried tightening the screw of the lever to stop it happening, but it was not entirely successful, and I concluded that just tightening more might well cause damage. I cured the problem by fitting some old Suntour Cyclone ratchet levers - these are, I think, the same as the modern standard Dia-Compe ratchet levers, except that I think the Cyclone levers have a smaller diameter barrel like the Simplex Retrofriction levers and other levers of the 6 speed era. My memory of using Suntour Powershift levers was that they had more friction/resistance to slipping than any other lever I used.

I never noticed pull-back with my rear derailleur, but my combination of an old 6/7 speed rear derailleur with a 6 speed block and 3/32" chain would be far less sensitive to small cable movements. A 10 speed cassette with its narrow sprocket pitch and narrow chain is likely to be more sensitive, depending upon the sensitivity/actuation ratio of the derailleur. A 10 speed MTB rear derailleur requires 48% more cable pulled to move the arm a given distance than a 7/8/9 speed rear derailleur or 10 speed road rear derailleur.

I have found no problem with shifting an 8-speed chain with a 10-speed Ultegra FD-6503 front derailer

FD-6503 is not a 10 speed derailleur; it is a 9 speed derailleur.

My experience of using an 8 speed chain with a 10 speed front derailleur involved a KMC chain, down tube levers and FD-5703 105 triple derailleur on a 25/38/48 chainset, with the derailleur set at the recommended 2mm above the big ring. Although I was only using a 7 speed cassette, rather than a wider 8, 9 or 10 speed cassette, I had to trim the front derailleur after most rear shifts to cure chain rub.

I can understand how mounting the front derailleur higher might be a solution and cure the rubbing, but Shimano's shaped triple cages are designed for specific tooth intervals between big and middle rings. In addition Shimano's triple front derailleurs (at least the 10 speed versions) are designed for different tooth intervals between big and middle rings depending upon what the interval is for the chainset of the derailleur's groupset. FD-6703 is designed for a 13 tooth interval, and FD-5703 for an 11 tooth interval. Therefore raising the derailleur might work with one but not the other, depending upon what big and middle rings are used.

would slip if I was out of the saddle - this was definitely lever slippage, and not due to frame flex

The lever slips because the cable tension is increased. That happens because the frame flexes during each cycle of the pedal stroke, alternately increasing and reducing the distance between the levers and derailleurs that the cables are routed along.

[ChrisF]

If it is not the shifter, that largely only leaves the rear derailleur. I suggest you provide photographs of it, viewed both side on and from the rear.

OK, thanks, here's some photos.

Galaxy rear mech 1

Galaxy rear mech 2

I know the cable end is a disgrace! It's 'cos I've been messing about with it so much - the cable itself is fairly new; I'll replace it again when I have sorted the main problem.
The inline adjuster was added a while ago in an attempt to solve the problem.

[slowster]

That is an RD-771 9 speed derailleur, e.g. see

https://www.tritoncycles.co.uk/componen ... rmal-p9077

https://www.richmondcycles.co.uk/produc ... op-normal/

Edit - It should work with either of the following combinations:

- Road or MTB 9 speed levers and a 9 speed cassette (or 8 speed levers and 8 speed cassette)

- Road 10 speed levers and a 10 speed cassette (i.e. what you have*)

* I sugggest you double check the levers - the speed and model no. should be printed in white lettering on the side of the lever's black dust shield, e.g. 'SL7700 9S'.

I think that diagnosing why your shifter is pulling that mech across the entrire cassette with only 7 clicks instead of the full 9 clicks is something that would require patient systematic investigation to eliminate all possible causes, e,g. checking the lever assembly, fitting another 9 speed derailleur as a control/comparison, checking the derailleur hanger alignment with a proper tool (just doing it by eye is not accurate enough IMO), in addition to going through the correct set up procedures for the derailleur from scratch (per https://manualzz.com/doc/53866408/shima ... structions)

I see that the cable is clamped on the correct side of the clamp bolt, and the cassette looks like Shimano (at least the lockring is Shimano), rather than another brand which might have different sprocket spacing, e.g. Campag or Miche.

Finally, if you fit ratchet friction levers, you might not need the Dia Compe levers with the large barrel. Since you have a 9 speed rear derailleur rather than a 10 speed MTB derailleur with its smaller actuation ratio, I think the standard Dia Compe levers* should be adequate, because their barrel size is the same as a Shimano 9 speed lever (as per my post here - viewtopic.php?p=1721276#p1721276).

* https://www.sjscycles.co.uk/gear-shifte ... n-control/

[ChrisF]

Slowster, thank you so much for all your input.
And now I realise that my memory has failed me; I have posted here before, nearly 8 years ago, with almost the same problem! viewtopic.php?t=95650
That thread started with me reporting slippage between the larger cogs, when I was using an 8 speed shifter in friction mode. The thread ended after I had swapped to my current Shimano 10-speed indexed (Yes, it's definately a 10S). At that point I reported that

In the workshop the indexing works fine, but out on the road there is an autochange every once in a while

.
Apart from adding the inline adjuster, no parts have been changed since then*, but the incorrect shifting is now very definately occuring on the workshop stand (i.e. with no lateral force on the frame). There's no wobble of the cassette on its hub.The bike has done 14000km since then, although not much of that in the last 3-4 years.

* I have probably changed the cassette (and chain) but it would have been to the same type, and I always buy Shimano cassettes.

My next step will be to take everything apart, clean it and reassemble from scratch, and at least see if I can revert to the 2013 situation, which was evidently not bad enough for me to ride 14000 km, much of that with luggage including a 3-week camping trip across France, which was started only a few months after my orignal thread was posted.

[fastpedaller]

would slip if I was out of the saddle - this was definitely lever slippage, and not due to frame flex

The lever slips because the cable tension is increased. That happens because the frame flexes during each cycle of the pedal stroke, alternately increasing and reducing the distance between the levers and derailleurs that the cables are routed along.

Absolutely not...... I could see and feel the lever moving. It was due to the extra torque being put through the drivetrain causing the mech to move sideways. The same bike with the same shifter (but in index mode) remains fine and has never slipped a gear since.

[slowster]

That thread started with me reporting slippage between the larger cogs.

I would very much suspect the derailleur hanger alignment in that case. I think misalignment is more likely to affect shifting when the derailleur arm is furthest away from the hanger, i.e. on the largest sprockets.

Moreover, I think that the larger those sprockets are, the more likely it is also that misalignment will affect shifting. When I replaced a 10 speed 11-28 cassette with an 11-32 cassette, the effect on the indexed shifting was like night and day and the indexing went to pot immediately. Although I did not have a derailleur hanger alignment tool, I was in the fortunate position of not only having a spare derailleur and being able to fit the old cassette back in order to experiment, but I also had a spare brand new derailleur hanger. I found that the new derailleur hanger cured the problem, and when I got hold of an alignment tool I was able to refit the old hanger and bend it back into alignment for perfect shifting.

The sort of slight bend in the hanger that might be found in a steel frame like a Galaxy after a fall or crash would probably be unnoticeable and have no effect on non-indexed shifting with a 6 speed 13-28 block. However, fit a 10 speed 11-36 cassette and indexed shifters, and that small misalignment may no longer be unnoticeable.

Assuming you do not have an alignment tool, my suggestion would be to use a spare rear wheel, albeit possibly only to check the alignment (I am not sure if it is good enough for correcting misalignment, especially for the more finnicky and intolerant transmissions with more speeds). EDIT - If you found that there was misalignment, it might be best to get it fixed at a shop. More cyclists nowadays are buying alignment tools, but that is because they usually have frames, often MTBs, with replaceable aluminium hangers which are more likely to get bent than a steel hanger



This video shows how to make a DIY tool like most of the various proprietary tool designs: