new chainset

[Blodwyn Pig]

ok don't panic, problem solved. Just won on e-bay, a new (well 20 miles) stronglight, impact2 , (with the 5 exposed spider arms, no longer made), with new rings, minus 1 bolt,  in 175mm flavour, 46,36,26 for £53.00   I have an almost unused 24 t granny, so I can play with it all.   Also bought a un55 from Wooly hat shop. So new chainset, bb,chain and rear asette, next weekend , to be fitted,  think.

Soon be selling my Campag Centaur chainset and bb. 

[Brucey]

BTW you could always keep a different cassette and chain to fit when you go loaded touring.

cheers

[Blodwyn Pig]

BTW you could always keep a different cassette and chain to fit when you go loaded touring.

cheers

indeed I have a 13-34 that the bike came with, and the XT rear mech. BUT I'm using a Veloce rear mech at present, and it wont accommodate 34t, hence lowering the other end, . Thanks all!

[andrew_s]

slightly ot, but on the stronglight impact chainset with 4 visible spider arms, the  chainring has an insert for the hidden spider, does this just push/tap out?

Hi Blodders. I've just examined a Sugino XD2R crank (which I believe is functionally the same) and the hidden fixing uses the standard chainring nut & bolt but with the nut outwards and the bolt fitted from the inside.

It's not a standard nut & bolt.
The outer "nut" part has serrations on the outside, so it's a tight fit in the chainring, a chain nut tool not being usable. It would normally stay put in the chainring and need tapping out with a mallet.

A problem with the Spa Zicral chainrings is that the hole is a fraction larger, and the serrations aren't enough to stop the nut spinning as you tighten the allen bolt.

[Kim]

A problem with the Spa Zicral chainrings is that the hole is a fraction larger, and the serrations aren't enough to stop the nut spinning as you tighten the allen bolt.

I've found that a combination of strategic application of gravity, a flathead screwdriver and harsh language gets the job done.  Once it gets tight it holds itself in place, fortunately.

[Brucey]

if you take the two halves of the bolt, clean and grease the threads well, and run the inner into the sleeve fully and back it out again, making sure there is absolutely no binding, then only the slightest holding of the sleeve part is sufficient during assembly. For example a tiny blob of blu-tac on a hidden bolt sleeve is enough, or a fingertip on a normally positioned bolt.

NB the only parts of a chainring bolt assy that should be greased are the bolt/sleeve threads. If a tiny bit of grease gets under the head of the bolt it does no harm but if other parts of the assy are greased then it often does harm rather than good.

If the bolts and sleeves are well greased,  run in and out of one another fully, and checked for any binding as suggested above, you never need a spanner to hold the sleeve with a spanner when assembling these bolts and only if they are undisturbed for many years do they cause any trouble when being disassembled, either.

cheers

[Samuel D]

it's veering off-topic but while i dislike 11t sprocket for it's inefficiency, i need it for the chainrings of 50t or less otherwise i spin out on the downhills.

Is someone forcing you to keep pedalling? I tuck and coast alongside people who believe that. It’s as if someone is holding a gun to their head and threatening to pull the trigger if they miss a pedal stroke!

just came back from a training ride on my ss bike (79"), two thirds of the ride spent spinning like a loon between 40-50kph. it's good in terms of training, but not exactly enjoyable.

Well, in that case I understand the need for tall gears. Even Froome’s epic training rides earlier this year were a lot slower than that.

I’m talking about mere mortals whose average speeds are under 35 km/h on mixed terrain despite the help of a strong group. In that case, the most you need is a gear to keep up with the frantic 50 km/h charges on the flat. For that, 46Tx13T (95") is plenty.

[zigzag]

if the whole group keeps pedaling it keeps a nice rhythm if everyone does the same. if you start coasting or spinning like crazy in the middle of group, people will be very cautious riding around you, it's best if everyone rides smoothly and predictably. there's no need make comparisons with the pros, we are a bunch of dilettantes riding for fitness and fun, but that doesn't mean that given the right conditions the speeds are dissimilar. most amateur races will average ~40kph, pros achieve a few km/h more (which requires 1.5x effort..).

[Oxford_Guy]

What's actually involved in the process of making up a custom 9-speed 13-32 (or 12-32) cassette? What tools are required? If any rivets have to be removed, then I guess that's going to require grinding the heads off, but I don't think I have any tools that would do this job - would a Dremel work? I don't have a Dremel yet, but it could be excuse I need to buy one...

I assume you don't need to re-attach any rivets as the cogs will be held in place by the lock-ring once on the bike?

Which model 11-28 (Shimano compatible) cassette would be a good starting point? Guess you want something with a 13T as the second cog, but these seem rare. Maybe start with a IRD 12-28T Comp?: https://www.sjscycles.co.uk/cassettes/1125-ird-comp-9-speed-cassette-shimano-compatible/

This goes: 12, 13, 15, 17, 19, 21, 23, 25, 28T

So would then be after modding: - 13, 15, 17, 19, 21, 23, 25, 28, 32T

Which sounds quite usable.

Also can I buy just a 32T cog separately, or would this need to come from a donor 11-32 cassette? Sounds like you won't have to change that cog as often as the other ones, though.

[Brucey]

you don't need any special tools or to take rivets out if you are only trading the smallest for the largest sprocket. Some pointers;

1) you do need a spacer with cutouts in it for the new #1 sprocket, if the rivets protrude much out the back of the old #1 sprocket

2) the larger #1 sprocket can be bought new or snagged from a used cassette; they rarely get used enough to get worn badly

3) you may benefit from a different lockring because the #8 sprocket will usually have serrations in a different place than a 11T lockring will engage with.

4) if the original lockring goes into a recess in the #8 sprocket it may require a spacer to grip the sprockets properly

5) it is OK to use a little threadlock on the lockring threads if the serrations don't engage.

6) If you have to, de-time the larger #1 sprocket by removing part of the large spline, and use the freedom of movement to get the HG ramps to line up properly.

cheers

[Oxford_Guy]

Thanks Brucey!

A few questions:

Where can I get a spacer with cut-outs in it for the new #1 sprocket from?

It looks like quite a few (not all) cassettes have loose sprockets for the #8 position,  that can probably be removed easy enough, but many seem to have the #1 sprocket fixed to a carrier (like my current Shimano XT 11-32 cassette, in fact all sprockets are fixed to a carrier for that cassette), not sure how one can be sure when buying a cassette with a 32T sprocket whether that sprocket (and the #8) is easily removable?

Where would I source a different lockring from? If, for example, I'm trying to make a 13-32 cassette, does that mean I need to use a locking from a cassette that starts on 13 (e.g.a 13-25)? If so, then this implies you'd have to use 3 cassettes to make a 13-32 one, or can lockrings be purchased seperately?

Where can I get the sort of spacer mentioned in point 4?

Not sure I fully understand point 6...

This is starting to look a bit too complicated for me and my limited workshop skills... :-(

Also, looking at geat calculators and thinking about my use cases, I think a 12-32 may actually work better for me than a 13-32 - with a 46T front ring the highest gear would 112.9" for 11T, 103.5" for 12T, but only 95.5" for 13T - this compares to the 103.1" I currently get from an 11T cog with a 42T front ring, which is a gear a use every morning when cycling down a long hill to get to work (could even do with a bit higher). I don't think I would want to reduce my highest gear to less than 100". IRD do an off the shelf 12-32 cassette in their lower-end "Comp" range (SJS sell this) - the small gaps between the gears sound quite nice, but is the smoothness and speed of shifting likely to be worse than my Shimano XT 11-32 cassette? The IRD cassette is certainly heavier!

IRD Comp 12-32 (Shimano-compatible)

12, 13, 14, 16, 18, 20, 24, 28, 32T

Shimano XT 11-32

11, 12, 14, 16, 18, 21, 24, 28, 32T

So the IRD would have smaller gaps between 12 and 14 (due to the additional 13), and only 2T difference, instead of 3T, between 18T and the next cog. The gap between 24T and the next cog down is one larger, but that's less of an issue.

[DuncanM]

Hi Oxford_Guy
If you need tools/skills that you don't possess, or random odd bits, it might be worth popping into the "Broken Spoke Workshop" in the centre of town. They have all the bike shop tools one could need, plus a mechanic who can show you how to use them if necessary. You can find out more (and workshop hours) here: http://bsbcoop.org/
Cheers
Duncan

[Ian H]

On the touring/audax bike I've run a triple with 13-26 on the back for years.  Currently the rings are 48-38-26 on TA cranks.  The 26 doesn't get all that much use, but occasionally is essential.

[Oxford_Guy]

The Harris pre-made custom "Century 12" also looks interesting (though expensive) for my 46/34/24 chainrings - would give a range of 23.4" 21.6" to 103.5" from the following sprockets:

12, 13, 15, 17, 19, 21, 24, 27, 30T

From: https://harriscyclery.net/product/harris-custom-century-12-12-30-9-speed-cassette-2369.htm

Not sure that 23.4" is going to be low enough for touring with camping gear, though... EDIT: I got that wrong, would be a bottom gear of 21.6", which is definitely sounding more usable for touring...

[Ian H]

Not sure that 23.4" is going to be low enough for touring with camping gear, though...

Only you can decide that.

[Oxford_Guy]

The Harris pre-made custom "Century 12" also looks interesting (though expensive) for my 46/34/24 chainrings - would give a range of 23.4" to 103.5" from the following sprockets:

12, 13, 15, 17, 19, 21, 24, 27, 30T

From: https://harriscyclery.net/product/harris-custom-century-12-12-30-9-speed-cassette-2369.htm

Not sure that 23.4" is going to be low enough for touring with camping gear, though...

Think the 30T is also not on an aluminium carrier, but loose, though pretty sure I have a steel cassette body on my Hope RS-4 hub, so hopefully it wouldn't chew through that...

[Oxford_Guy]

BTW if you don't know about it already, this site has a great way of visualising different gearing setups:

http://ritzelrechner.de/

[Moleman76]

So Brucey,what cassettes are you using that start at 13/14 . Home brew? What range? 

not Brucey, but here's my solution (in the Shimano family):

Chainset: 48-38-24
Cassette: 9-speed, blending a "junior" cassette starting at 13 with a "wide range" one ending in 28.  (There are also such starting at 14T). 
   so, the 13-25  (13/14/15/16/17/19/21/23/25) plus one that ends up with 21/24/28.   At the more-teeth end, the jumps between number of teeth would like to be bigger, since a 2-tooth difference at the more-teeth end doesn't make the same difference as it would down at the less-teeth end.    So, 13/14/15/16/17/19/21/24/28 has steps of 1,1,1,1,2,2,3,4.

These cassettes - in order to get interchangeability and making substitutions where you want, versus where the machined block of cogs are set up - are often not the top-end models (so they weight a hair more, and cost a lot less), and are often in shorter supply at the retailers, but with patience can be found.

Sheldon Brown's site has color coding to show which groups of cogs are on "spiders", so you need to be careful about where you can trade.  If they're just riveted, no problem with unscrewing or grinding off rivets. 

[Brucey]

The IRD cassette is just horrible.

 I spent a long time typing a reply explaining why and answering your other questions but the daft forum settings (pages time out on you, and then your browser won't go 'back' to your draft regardless of how you have your settings, it seems) means that is all lost now. I 'copied' the text just in case and it ate that too. Bloody annoying.

Many of the other suggestions would instantly end up in the Brucey reject heap because they (like a typical compact double) force you to use a crappy chainline onto the sprockets you use most when just tapping along.

For example with a road triple, sprocket #6 is the one with the best chainline onto the big ring and it is a very good idea to set this to be the favoured tapping along gear.

So 12, 14, 16, 18, 20, 22, 25, 28, 32 and  a 46T big ring gives you a nice 46/18 tapping along gear and easy access to low gears for loaded touring

You can get a 22T sprocket in some BBB cassettes I think.

For the other points just get stuck in, and all will become clear.

cheers

[ElyDave]

All this is making me wonder whether I need a 12-30 on my cruzbike for my summer tour, currently have 12-28 and 52/39/30 on the front.  I guess this weekends's audax will be a good test.

[Kim]

All this is making me wonder whether I need a 12-30 on my cruzbike for my summer tour, currently have 12-28 and 52/39/30 on the front.  I guess this weekends's audax will be a good test.

Given that getting off and pushing is a complete pain on recumbents, and that low speed balance is generally improved by higher cadences, I'm of the opinion that if you're going to be carrying any kind of load you can never have too low gearing.

I suppose the Cruzbike's FWD means you can't take the usual darkside liberties with chainline and undersized granny rings...

[Oxford_Guy]

The IRD cassette is just horrible.

In terms of general quality? Shifting? Are BBB and Miche cassettes any better?

I spent a long time typing a reply explaining why and answering your other questions but the daft forum settings (pages time out on you, and then your browser won't go 'back' to your draft regardless of how you have your settings, it seems) means that is all lost now. I 'copied' the text just in case and it ate that too. Bloody annoying.

Argh! I've had that happen with other forums -  have taken to typing out longer replies in a text editor first, then copy and pasting into forum posts

Many of the other suggestions would instantly end up in the Brucey reject heap because they (like a typical compact double) force you to use a crappy chainline onto the sprockets you use most when just tapping along.

For example with a road triple, sprocket #6 is the one with the best chainline onto the big ring and it is a very good idea to set this to be the favoured tapping along gear.

So 12, 14, 16, 18, 20, 22, 25, 28, 32 and  a 46T big ring gives you a nice 46/18 tapping along gear and easy access to low gears for loaded touring

You can get a 22T sprocket in some BBB cassettes I think.

Those ratios look nice, but now need to figure out which hack-able cassettes would give me this

For the other points just get stuck in, and all will become clear.

Your confidence in my mechanical aptitude is generous, if perhaps mistaken

[Oxford_Guy]

Hi Oxford_Guy
If you need tools/skills that you don't possess, or random odd bits, it might be worth popping into the "Broken Spoke Workshop" in the centre of town. They have all the bike shop tools one could need, plus a mechanic who can show you how to use them if necessary. You can find out more (and workshop hours) here: http://bsbcoop.org/

Not a bad suggestion, I used to go to it's previous incarnation, the Oxford Cycle Workshop, many years ago...

[Oxford_Guy]

Assuming they can be tracked-down (seeing as it looks like they've gone into liquidation) are the sprockets that Marchisio produced any good? Looks like you can build up complete custom cassettes with these, though tracking a complete set down might be tricky...

[Brucey]

the IRD cassette is horrible because of the ratios. The cassette suddenly jumps from 2T  to a 4T interval leaving a huge gap between the gears vs the other intervals.

BBB model BCS 09S exists in many flavours and some have unique sprockets not found in other cassettes; for example there is at least one which has a 22T sprocket which does not exist in other designs. They do a very handy 13-25 and they do a 12-27. Either could be modified to give a touring cassette or used 'as is' for other purposes. The lockring they use on most cassettes will work with a 12T to 14T top sprocket. Various retailers including triton, tredz, winstanleys, ribble etc usually have them. Prices start at about £13 and go upwards from there.

Frustratingly I failed to find a list with all the BBB cassette builds on, so intermediate sprockets are not certain in every case.

cheers