Is there 8 speed and 9 speed Sora?

[Watchman]

I built my son a lovely bike around a Planet X London Road f&f - simple "tow path" flat bar 1x8 with decent but budget-ish parts. Cost about £700 in total if you totted-up the value of some of the parts I used that I already had.

But, I only had an 8-speed (32-11) cassette and chain at the time, which I successfully paired with a Shimano Sora 9-speed shifter by setting the derailleur's higher limit to prevent it clicking that last time.

It's been very successful but I have been gifted a brand new 9-speed Shimano cassette (34-11) and chain which all bolted onto the bike easily enough but I cannot index the gears successfully.

I have checked that the hanger is straight (I have the Part Tool hanger straightener), and set the upper and lower limits. I have included 2 additional links to the chain above the original to account for the additional 2-teeth of 1st gear. The shifter is a Sora 9-speed and I definitely get 8-"clicks" in each direction if I relax the limiter screws (chain falls off but I wanted to prove this). The derailleur is a medium length one.


I can get the smaller 6 sprockets indexed quite nicely but not the larger ones. Going from 4 to 3, it always skips to 2. It's as if the derailleur is an 8-speed Sora and doesn't have the granularity to handle the 9-steps.

Is that possible? Nowhere on the derailleur does it mention it is tied to a specific number of steps. The only mention of steps is on the shifter.

I appreciate any help you can offer.

[Watchman]

I didn't think to look there. I'll check it out. Thanks.

Although the shifter is the index, I wondered whether the amount of travel determined by the indexing might be different for an 8 and 9 as the translation to the derailleur covers the same distance highest to lowest. It's the granularity that is different. However as my 9-speed shifter worked as an 8... Oh it's complex. I'll check out the oracle.

Thanks again.

[Watchman]

Looks like I'm going about things the right way, and there is no 8-speed Sora - only 9-speed. I've looked through my records of when I came to own the various parts too and I can confirm they were labelled as 9-speed. I'm perplexed why it worked as an 8-speed now.

The adjustment screw that determines the distance of the cage from the larger sprocket is set right - there's no contact and the derailleur seems to hang a "decent" distance from the cassette all the way through the movement. The chain length wasn't very scientifically calculated so although it looks right, I'll have another look tomorrow. I will probably remove the derailleur completely and start all over with another check of the hanger and I'll relax the H limiter screw because that's not really necessary of the cable tension doesn't allow the chain to move beyond the smallest sprocket.

I don't have a lot of hope and I'm frustrated because I am usually competently mechanically-minded - I built a Caterham, including its engine, and I kept a TVR alive for a while (harder than building a Caterham). I can usually do everything on bikes but I confess gear indexing is the one thing that sometimes gets the better of me.

I'll report back.

[Watchman]

Thank the tech giants for online purchasing records. Looking back at when I originally bought the bits, they are:

Sora RD 3500 short cage derailleur 9-speed
Sora SL 3503 shift lever right hand 9-speed Z03R

My only concern is that they claim a short cage is only to be used up to a 32 tooth lower sprocket however two things:

1. Engaging that largest sprocket isn't the problem. It all indexes wrong at 3rd and 4th

2. Despite the description, the cage seems quite long. I assume we're talking about the distance between jockey wheels, or is it the distance between spigots on the parallelogram that I should be measuring?

[Watchman]

Barchettaman said:

That should work fine.

Have you routed the cable through the pinch bolt correctly?

Is it running a 9-speed chain?

Yes and yes. Pinch bolt cable routing consistent with other bikes and actually unchanged from when it was successfully working as an 8-speed, and the chain is a brand new Shimano HG93. I'll stick a micrometer on it to check the outer measurement but it does fit comfortably between sprockets.

It's madness... but I'm going to strip it all off again tonight and start again with the hanger straightener, relax the limiters so that the chain is held on the H limit (smallest sprocket) by cable tension only, and take it from there.

[Watchman]

Barchettaman said:

Best of luck.

My questions weren’t questioning your competence, by the way, just troubleshooting and they were about the only things I could come up with!

I know. Sorry if I sounded defensive. Typing on a phone - sometimes I might be slightly more "brief" than intended and it may sound curt. Not intended. I thank you for your advice.

Barchettaman said:

If you set it up again and it STILL won’t work, try a 10-speed chain instead as a last resort. I’m running 9-speed drivetrain with a 10-speed SRAM chain on my commuter at the moment and it shifts really sweetly.

I can’t think of anything else....the bloody thing should be working fine!

A 10 speed chain is a good idea would certainly give more room to the sides to stop unwanted grinding.

The indexing between 4th and 3rd is so off, I think there's something more substantial wrong but I like that suggestion.

Thanks.

[Watchman]

GOATever said:

Have you changed the cable inners and outers in unison? The mech is a dumb ‘slave’ unit, as long as there’s enough spring and mech body length to cover the range of the cassette, they are governed by the mechanism in the shifter. I’d say it’s a safe bet that something is snagging the cable. Lube the cable inner and outer up, then re install, and check that all the grommets are firmly butted up and seated against the frame hooks, and the cable outers. Make sure the spring in the mech is moving smoothly, and that there’s no damage to any part of it ( can be caused by debris getting stuck in it, then causing damage when you shift ).

Truth is, the bike is quite new and relatively little used. The cables were all new when installed last year and I have repeatedly kept them in perfect order with occasional sprays with GT85 and a wipe of any dust. It feels less like there's any binding and more like the indexing spaces are wrong *just* for these few sprockets. The others work well.

Must be something subtle with my setup. I'll have another, more patient, go at it again tonight.

Thanks.

[Watchman]

Interesting. There were no spacers included with the new cassette and none came off the old one.

The two smallest sprockets of both cassettes were loose but they can only slide onto the freehub in one orientation because of the splines, so they mated-up quite properly.

The cassette is an HG400. A colleague wondered if MTB and roadie cassettes might be spaced slightly differently to match slightly different indexes associated with the MTB or roadie levers. Although the HG400 is an MTB version, and so is consistent with the entire kit on this bike, we both decided there couldn't be a difference or it would be flagged all over Google.

[Watchman]

R_von_S said:

I wonder if that's part of the problem - it should be sitting on the high limit screw with the cable removed. (And the barrel adjuster wound almost all the way in, not that it has any impact when the cable is disconnected, but you'll be ready to use it properly later).

http://www.cyclist.co.uk/tutorials/74/how-to-adjus...

I usually set them up by setting the limiters first but Sheldon Brown suggests the H limiter is largely irrelevant if the tension is right to hold the derailleur on the smallest sprocket, and in that circumstance the tension should be right for all sprockets.

He has a point. I'll give it a go.

[Watchman]

ChrisMCoupe said:

Is the 9 speed chain thinner than the 8 speed chain? If so, this could be your problem

It is by about a half mm...

7.1 to 7.3 for 8-speed (and 7-speed)
6.6 to 6.8 for 9-speed

I have a 9-speed cassette, chain, Sora shifter and Sora derailleur now.

[Watchman]

Success..!!

But I'm not 100% certain why.

I had another look at the hanger. As before, it's absolutely spot on, so I had a go at removing the H limiter and starting with a pre-tensioned cable as I described above. That didn't work.

I had a look at the B screw. I had it screwed quite a long way in, so I unscrewed it until it was too far and the jockeys were touching the cassette. However, even at this setting, the indexing was better than before so I carefully adjusted the B screw and tested the indexing until I got it all changing as slick as a rifle-bolt.

Very many thanks for all the advice and mostly for the confirmation that I must be on the right path. That was encouraging and gave me more confidence to continue instead of rushing off to a bike shop.

[Watchman]

Barchettaman said:

Hooray! Good work.

As you have found, even the cheaper Shimano stuff shifts beautifully once it’s nicely dialled in. You get the satisfaction of having sorted it yourself too. Bloody well done!

Quite right. I'm an engineer at heart so it's important for me to understand the worth in components. I looked at the more expensive kit and couldn't find that worth for the type of use we would put it to, and knowing (as you stated) how well even the cheaper Shimano stuff can work makes the purchase decision easier. In this case, the components were given to me - the consequence of some convoluted payment agreement I had with someone.

I've always done my own bike maintenance except once when I couldn't get my gears to index and took the bike to Cult Cycles in Earlswood (just outside Solihull). The first thing the chap did was to whip the derailleur off and straighten the hanger, something I hadn't even considered. Then he spent 3 mins making it all operate like a slick machine. That was £10 very well spent - partly for the fix but mostly for the lesson.

Since then, I've tried to bridge the gap since i stopped cycling (and self-maintaining) in about 1990 with the modern materials and methods by watching a lot of YouTube videos. I can do most things now including suspension forks but occasionally something doesn't behave the way you might expect and some encouragement to continue (because you're on the right path) is all it needs.

My lad is happy too.

[Watchman]

Julietbravo said:

Excellent! Hope the weather holds for a few more weeks and you get out on it. I recently rebuilt a Giant Defy from a bare frame with my lad - insert BB was the starting point, new cables, which way to wind the bar tape etc. I wanted him to be able to go out on it and know how it all works incase of a mechanical whilst riding.

When I built the bike last year, I tried to get my lad interested in helping but he was in the throes of building and refining a gaming computer at the time, so had no interest. However, he's been with me all the way with these changes, and put the new tyres on himself, so maybe we've reached a tipping point where he'll take more of an interest in future. I know I hoovered-up all my Dad's bike knowledge from about the age of 8yo but I didn't have the distraction of computers then (I'm 50yo now).

Since returning to cycling about 10 years ago, it's been a dual purpose - to do some exercise (I desperately need it), and to do a family activity. In both regards it has always been a massive success.