'Mullet' drivetrain headache

grumpy_turnip

Present situation....
Tiagra 3x10 4600 shifters
Tiagra crank with 50/41/30 chain rings
Deore RD-M592 9sp rear derailleur
11-36 HG62 10sp cassette
New hanger
New 10sp Shimano chain

With this little lot installed the RD movement is too small every click of the shifter so won't index correctly. I've set the limit screws on the RD and without the shifter cable in place it happily moves over the full range of sprockets without any problem. With the cable installed it's only covering 8 of the sprockets with all 9 clicks of the shifter.

  Last night I took the bike to a friend's house and fitted an old 10sp 105 shifter. I had exactly the same result. I guess that rules out the shifter being the issue. The RD looks visibly fine (it is a 2nd hand unit) and the jockey wheels appear inline with the cassette sprockets. I'm now a little confused as I understood a 9sp mtb RD operates on the same pull ratio as my 10sp road shifter but in my situation that doesn't appear to be the case.

Any help on this would be greatly appreciated.

GT

grumpy_turnip

I should add I've fitted a new gear cable which is moving silkily through the housing.

masjer

Hi
Is the cable installed on the correct side of the clamp bolt?

Munsford0

Since you appear to have ruled out the shifter, are you absolutely sure about the identity / speed / model number of the derailleur?

I too will be interested to hear if you fix this. My dry weather bike has a 10 speed 105 triple and the older I get the more I'm considering installing an MTB RD with a 36t cassette. I figure 30 x 36 should get me up just about anything

I've already done it on the winter bike, but that's running 9 speed Tiagra 4500 with a 46/36 CX chainset. The 9 speed MTB RD plays very nicely.

grumpy_turnip

masjer said:

Hi
Is the cable installed on the correct side of the clamp bolt?

Thanks for your input. Yeah, it's certainly been installed correctly, to be honest it'd be difficult to get it wrong with this particular derailleur.

grumpy_turnip

oxoman said:

Not familiar with tiagra other than some issues of compatability. Your set up seems OK. A quick Google and I spotted similar issue to yours and the guys rear mech cable routing had play or movement in it so that was stealing some of the movement required to move the rear mech correctly. Apparently shimano stopped this by doing the 4700 series which I believe is non compatible. Might be worth a Google and YouTube search as you won't be the first to have had issues. When you find the answer it's nice to out it on here for others to use. Good luck.

I have tried a good few Google searches and so far I seem to hit a brick wall. Everything I've found on the subject suggests this should work. However, it could easily be the wording in my search isn't good enough. What did you use?

GT

grumpy_turnip

Munsford0 said:

Since you appear to have ruled out the shifter, are you absolutely sure about the identity / speed / model number of the derailleur?

I too will be interested to hear if you fix this. My dry weather bike has a 10 speed 105 triple and the older I get the more I'm considering installing an MTB RD with a 36t cassette. I figure 30 x 36 should get me up just about anything

I've already done it on the winter bike, but that's running 9 speed Tiagra 4500 with a 46/36 CX chainset. The 9 speed MTB RD plays very nicely.

Yes, I must admit I'm wondering if I've got what I was told I was getting regarding the RD. It appears I have when I look at other pics of the same mech. The thing is that anything deore 9 speed or less should have the correct pull ratio to match the shifter I have. As I understand it anything 10 speed plus, which wouldn't marry with the shifter, would have a clutch involved and therefore easily recognised.

This is the RD presently installed on the bike....

Munsford0

That looks identical to all the pics of a M592 I can see online.
The only other thing which occurs to me is the loop of outer going to the mech. I'd only ever done road RDs before, with a large-ish loop of outer. When I fitted the 9 speed MTB mech it was clear that it needed a much shorter one. My initial attempt meant the outer was actually restricting the movement of the RD so I shortened it and all good.

Having said that, the angle of yours suggests it's OK. Be curious to see it when in the largest sprocket

grumpy_turnip

oxoman said:

I found it on this.
https://www.bikeforums.net/bicycle-mechanics/1106687-tiagra-4600-shifting-problem.html

Interesting stuff. Sadly it's not just one gear I have the problem with it's all of the darn things ! That said on the RD's way up or down the cassette I do have one cog that meshes perfectly, maybe my way forward is fixing it in that gear and simply changing the front derailleur to get a 3 speed system!

grumpy_turnip

Thanks for your assistance folks, I realise how difficult it is to offer advice when you can't get tactile with the subject matter. I think my next step is to find someone I know with an alternative RD that I can just fling on and see if that sorts the problem.

daniel_b

grumpy_turnip said:

Thanks for your assistance folks, I realise how difficult it is to offer advice when you can't get tactile with the subject matter. I think my next step is to find someone I know with an alternative RD that I can just fling on and see if that sorts the problem.

I think this could well be the right route to take.

I battled for ages with my partners 105 5700 10spd derailleur, and despite straightening the hanger, could not get it to index properly at all.
In the end, and partly because I wanted to get an 11-34 on there, I bought a brand new 105 5700 long cage, put it on, and had it indexed within minutes, literally, and I must have wasted many hours on the previous one

My theory is that she had fallen over in the past, all be it at low speed, and must have gone over on that side, so although the derailleur looked fine, it must have been marginally bent/twisted so it would never work for me.

On the subject of the rear hanger, have you got a tool to check it's alignment?
That has caused me issues with many rd's in the past, and is very useful in getting them plumb in line, or as good as you can do, with the frame.
Not sure how much they cost now, they are not a complex tool, but recall it costing around £20.

Any 2nd hand bike I buy, I pretty much always remove the RD and check this first off.

MidlandsGrimpeur2

As above sounds as though the RD could have been bent or is misaligned in some way. This can often result in poor indexing across most gears, but the odd one where it seems to mesh perfectly. Having had RDs bent out of shape a couple of times via crashes in the past, you can usually fettle them to get the shifting as close to the original performance as possible, but I appreciate in some instances it will never be quite right.

grumpy_turnip

It's definitely possible that the derailleur is out or damaged and that's a very good shout. Hmmm, do I know someone with a derailleur alignment tool (rubs chin)? I think I must. If not I'm sure the LBS could help me out. Cheers guys

DeVlaeminck

Are you sure the cassette is 10 speed ?

grumpy_turnip

DeVlaeminck said:

Are you sure the cassette is 10 speed ?

Not sure if this was said tongue in cheek but I'll certainly go with it. Yes, definitely a 10 speeder. This is the cassette in question...

masjer

Is the derailleur installed on the hanger correctly?
There is a small peg (on the mech) that rests against the hanger before tightening the mounting bolt. I can't quite see on your pic, but there might be a gap.

grumpy_turnip

masjer said:

Is the derailleur installed on the hanger correctly?
There is a small peg (on the mech) that rests against the hanger before tightening the mounting bolt. I can't quite see on your pic, but there might be a gap.

Thanks for your response. I believe I did, I seem to remember trying it in at least 2 positions. However, no matter where it was sat I believe that wouldn't prevent the RD from moving across the range of the cassette when the cable's connected to my shifter, of course I could be wrong and very often I am.

I do have an update on this, just penning it now....

grumpy_turnip

Just a little update on my progress with this. I hadn't had time to take another look at the bike until yesterday. Armed with a couple of 10sp quick links I set about fitting a known working Sora 9sp medium length cage RD. I had to swap the cassette to a smaller range, there was a handy 10sp 12-28 kicking about, as the Sora unit couldn't cope with the 36t of the one I ultimately want on this set up. So, all installed and I managed to dial it in pretty well. The RD moves fine across the range of the 10sp cassette, hurrah! Certainly a step in the right direction.

This leaves me still needing an RD that'll work with the 11-36t cassette installed, any suggestions folks? I'm also left wondering why the 2nd hand RD I bought doesn't work. I'm presently sat with it in front of me and can't see that it's bent in any way. What I haven't done is positively identified it as being what I was actually sold. I'm hoping you folks could help me with this. So, it's supposed to be a Deore RD-M592-SGS 9sp unit. Here's a few pics....







Is this RD what it's supposed to be?

Thanks in advance.

GT

grumpy_turnip

A further update and finally THE ANSWER!!

After more searching and reading I've eventually found that the derailleur I bought as a 9sp M592 is in fact a 10sp M593. The two derailleurs are very similar looking with the main difference being a longer arm where the gear housing connects to the derailleur body on the M593. The 10sp unit isn't compatible with my road shifters or, for that matter, any road shifters at all!

I was so close to finding this out weeks ago after Munsford0 suggested that I make absolutely sure that I have what I think I have. I found M593 printed on the rear of the RD's parallelogram so I duly typed RD-M593 into Google. What came back were pages of replacement jockey wheels. I wrongly thought that they must be coded M593 and these must therefore be the replacement wheels for my derailleur and ended my search. If I'd only gone a little deeper the answer was a short scroll further down the page! You live and learn.

I've lost over a month but at least I have my answer and I'm a bit more knowledgeable from the process too.

Munsford0

Top work on finally unravelling the mystery! And bonus points for coming back here to update us.

Why don't Shimano stick the model number somewhere more accessible.....

veronese68

Yes, thanks for confirming, hopefully others may benefit from your pain.

jon_greengrass

The cable pull on Tiagra 10sp shifters is only compatible with Tiagra 10speed, GRX 10 or 11s, 105 11sp, Ultegra 11sp and Dura ace 11sp Derailleurs.

to run the wide ratio cassette you either need a GRX rear derailleur, or get hold of a set of secondhand 10sp 105, Ultegra or Dura-Ace brifters that have the same cable pull ratio as Shimano 9sp MTB rear derailleurs. I am running Ultegra 10sp brifters with an old 9sp XT mtb derailleur and the shifting is perfect across an 11-36T 10 sp cassette

Edit: see whyamihere's post , I was wrong, I didn't know that about the 4600 series Tiagra, I thought that 4700 was the 1st 10sp Tiagra group Shimano has produced,

whyamihere

jon_greengrass said:

The cable pull on Tiagra 10sp shifters is only compatible with Tiagra 10speed, GRX 10 or 11s, 105 11sp, Ultegra 11sp and Dura ace 11sp Derailleurs.

That's correct for Tiagra 4700 series, not for 4600.