New front chain rings - not able to use small one

[Peter Scandrett]

Hi

Please forgive my terminology here as I think I might end up describing
things wrongly but I hope it's clear. I'm after a bit of advice please.

I have a ~12 year old Raleigh 'Jackal' bike, technically a mountain bike
but in practice I don't use it on mountains(!) but just towpaths/tracks,
that sort of thing. The front cogs (chain rings?) were horribly bent and
needed replacing so a few weeks ago I took the bike into my LBS
(localish, anyway, in Chorlton, Manchester) to have it looked at/bashed
back to shape/a new one fitted, and also to check over the gear
mechanisms etc. I got a quote over the phone for a new front ring set
and some pedals ("they look seized" - they were actually new a year or
so ago but who was I to argue? They were cheap and I was on the end of
the phone). I'd asked for new front cogs that were the same as the old
ones - mainly because I was comfortable with them.

When I picked it up the other day they'd fitted some bright silver
Shimano cog/pedal arm (crank?) combination which I wasn't overly keen on
(as the rest of the bike is black and red) but I went with it; when I
picked it up I was in two minds to formally comment on it (other than me
just saying "Hmm, silver") but I decided not to worry; they'd fitted it,
cleaned up the rear gear mechanism and looked it over so I was happy
enough. On reflection I wish I'd said I didn't like the silver colour of
the front unit but in the great scheme of things it's not the end of the
world.

Anyway, that's all by the by and largely irrelevant. I decided to go out
on my bike today as for the first time in ages a) me being not
completely ill and tired, b) it being a nice day (albeit cold) and c) me
not being at work all coincided.

To cut a long story short, I discovered that the front gear wouldn't
shift onto the smallest cog. I ended up standing in the middle of a
frozen field which, although it wasn't entirely unpleasant in the sun,
was cold - and all I had with me were my emergecny tools to try to fix
the problem. I rang a friend because I knew enough about the gear system
to try to adjust the two screws on top (the end stops?) but needed to
know which one did what and which way to turn them - only able to turn a
screw 1/4 turn at a time using my multitool meant I wanted to know what
I was supposed to be doing.

The practical upshot of all this and half an hour of me standing around
trying to sort this out is that I took the end stop screw out completely
(ie so there /was/ no artificial end stop small-cog-wards) and still the
chain wouldn't shift onto the smallest ring. In the process I'd managed
to stop it shifting to the larger cog too, so I gave up and went home
after only a couple of miles :-( I've since got it working on the large
one again.

So - can I have some advice please? Do I need to bend the gear arm thing
so that it will push the chain onto the smallest cog (I was reluctant to
do this on the ride and still would rather not)? Have the rings been put
on the bottom bracket(?) too close to the frame so it can't shift to the
small one? What else might have changed that I can fix (and how)?

For what it's worth, the gear cable and control thing on the handlebar
seem to be fine and it seems to be an adjustment thing at the pedal end.

I must admit that I'm not terribly impressed with the LBS in question;
they're OK, I suppose, but nothing to write home about. They replaced my
bottom bracket and chain last year without mishap (but wouldn't give me
my old chain back when I asked them - I wanted it because it had a quick
link but also because I wanted to clean it up and use it for something
completely different); this time I sort of assumed that when a LBS
replaced the chain ring unit they'd adjust the gear mechanism to go with
it but evidently not - is this normal? I didn't explicitly specify that
I wanted it to be done so I suppose it's my fault.

Sorry that's a bit long and it may seem I'm asking for my hand to be
held but I've had a look at http://www.sheldonbrown.com/ too and I'm
just a bit unsure on how to fix this as I've tried to fix it by
adjusting the stops as he recommends and just run out of movement on the
arm thing as the frame gets in the way.

Any thoughts please?

Many thanks

Peter

--
http://www.scandrett.net/lx/
http://www.scandrett.net/bike/

 

[POHB]

On 21 Dec, 14:21, Peter Scandrett <[email protected]> wrote:
> So - can I have some advice please? Do I need to bend the gear arm thing
> so that it will push the chain onto the smallest cog (I was reluctant to
> do this on the ride and still would rather not)? Have the rings been put
> on the bottom bracket(?) too close to the frame so it can't shift to the
> small one? What else might have changed that I can fix (and how)?
>
> For what it's worth, the gear cable and control thing on the handlebar
> seem to be fine and it seems to be an adjustment thing at the pedal end.
>
> I must admit that I'm not terribly impressed with the LBS in question;
> they're OK,

No they're not. They're rubbish. Go back to the shop and either get
it sorted or get your money back. Of course they should have adjusted
your gears to work when they replaced them. If you took a car to a
garage to get a new gearbox fitted you'd expect to be able to change
gear when you got it back. Don't start bending things because that
might give the shop an excuse not to sort it out.

> I sort of assumed that when a LBS
> replaced the chain ring unit they'd adjust the gear mechanism to go with
> it but evidently not - is this normal? I didn't explicitly specify that
> I wanted it to be done so I suppose it's my fault.

No it's not.

> run out of movement on the
> arm thing as the frame gets in the way.
>
> Any thoughts please?

I was going to suggest that the cable might need to be disconnected
and slackened, but if the frame is in the way then that's not going to
help. The new crankset has not been correctly fitted. Maybe it needs
some spacers or maybe it isn't the right size. Whatever, the shop has
stuffed it up and should fix it.

 

[Paul Boyd]

On 21/12/2007 14:21, Peter Scandrett said,

> Please forgive my terminology here as I think I might end up describing
> things wrongly but I hope it's clear. I'm after a bit of advice please.

<SNIP>

Like POHB says - the LBS should have made sure that everything worked
before it left the shop.

It sounds like the cable may been tightened too much with the stop in
the wrong place, so that even though you've taken the stop off, the
cable is still holding the derailleur back. It's also possible that the
new chainset has a different chainline to the old so that it will never
be possible to use your existing derailleur. Again, your LBS should not
have let it leave the shop like that.

The work your LBS has done is not up to standard, so you need to take it
back and make them fix it. Above all, don't bend anything and don't let
them try to take more money off you!!

--
Paul Boyd
http://www.paul-boyd.co.uk/

 

[Pete Biggs]

Peter Scandrett wrote:
> Sorry that's a bit long and it may seem I'm asking for my hand to be
> held but I've had a look at http://www.sheldonbrown.com/ too and I'm
> just a bit unsure on how to fix this as I've tried to fix it by
> adjusting the stops as he recommends and just run out of movement on
> the arm thing as the frame gets in the way.

Sheldon also mentions the height and angle of the front derailleur. The
whole derailleur might need re-positioning. Get your LBS to do it if you're
not confident to experiment more yourself.

Sorry for not writing instructions but that would be quite a big article and
it's already been done - by Sheldon Brown, Shimano, Park Tools, etc.

~PB

 

[Peter Scandrett]

Hi

POHB wrote on 21/12/2007 14:35:
> On 21 Dec, 14:21, Peter Scandrett <[email protected]> wrote:
>> So - can I have some advice please? Do I need to bend the gear arm thing
>> so that it will push the chain onto the smallest cog (I was reluctant to
>> do this on the ride and still would rather not)? Have the rings been put
>> on the bottom bracket(?) too close to the frame so it can't shift to the
>> small one? What else might have changed that I can fix (and how)?
>>
>> I must admit that I'm not terribly impressed with the LBS in question;
>> they're OK,
>
> No they're not. They're rubbish. Go back to the shop and either get
> it sorted or get your money back. Of course they should have adjusted
> your gears to work when they replaced them.

Righto, thanks (and to others who've replied). I was trying to avoid
taking it back because a) it's more faff and time and b) I'll obviously
not have it over Christmas - which isn't a major problem but it is a bit
of a hassle if nothing else.

Thanks for the advice though.

Peter

--
http://www.scandrett.net/lx/
http://www.scandrett.net/bike/

 

[Mark T]

> Any thoughts please?

Front mechs are a work of Stan, and will often play up when the chain is
towards one end of the rear sprockets but work fine when you shift the
chain towards the other end of the rear sprockets. The shop might have
checked it was working, but not checked properly.

It is possible that they didn't touch the front mech or cables as most
shops charge for adjusting the gears. Possibly not good service but then
I'm not sure what other shops do.

I've heard good things about Ken Foster's Cycle Logic so if they fitted the
chainset I'd hope they'd set things right while you wait. If not, I think
I'm fairly local to you.

Mark.

 

[Peter Fox]

Hi,

(1) A bit of mechanical knowledge with bikes is a good thing, but as you say
learning about it in the cold is not the ideal method.

(2) I'd be very surprised that a bike shop would fit a chain ring etc. without
checking the gear action, although perfection is sometimes hard to achieve
without a trip or two on the road. Therefore I'd ask how you transported the
bike between home and LBS. If this involved stuffing into back of car or
manhandling onto roof rack 'something may have been bashed'.

(3) How it works
(a) There's a 'puller' marked 1-2-3 on the handlebars...
(b) ...connected by a cable...
(c) ...via a cable guide (flexible tube) and often a cable guide
(saddle-shaped groove) on bottom bracket...
(d) ...terminating in a cable clamp on the actuator arm.
Pulling more on the cable brings the actuator into the frame more which
drags the chain onto the lower gear ring. And vice versa.

(4) Why it doesn't work in your case
(a) Either there isn't enough pull getting to the actuator
(b) Or the actuator is prevented from moving enough.
To see which of (a) or (b) is the case you turn the bike upside down,
crank the gears round by hand and pull on the exposed gear cable
running up the bottom tube. If you can get the gears to go into
bottom then the problem is (a). If you feel the actuator getting
to some mechanical obstruction then problem is (b).

FWIW I suspect your problem is (a). The puller may have got
knocked during transportation or the cable may have jumped
out of the vee-guides. You should be able to fix this
at home. You may need to 'shorten the cable' by releasing then
retightening the cable clamp on the actuator with more 'end' spare.
Work out how the little knurled adjuster works on the puller and
get this /fully/ into your head so you can make small adjustments (which
are generally necessary to get perfection across the whole gear
range) on test rides. (One way to do this is to twiddle the adjuster
with one hand while your finger is on the actuator. You should be
able to feel the actuator move.)


Some not so good news. If the chain hasn't been changed be prepared
for some jumping when under power. It is generally reckoned to be
a good idea to change the whole bloomin' lot all together (front, rear
and chain.)



--
Peter Fox
Beer, dancing, cycling and lots more at www.eminent.demon.co.uk

 

[Rob Morley]

In article <[email protected]>, Peter Scandrett
[email protected] says...
<snip>
> To cut a long story short, I discovered that the front gear wouldn't
> shift onto the smallest cog.
>
> So - can I have some advice please? Do I need to bend the gear arm thing
> so that it will push the chain onto the smallest cog (I was reluctant to
> do this on the ride and still would rather not)? Have the rings been put
> on the bottom bracket(?) too close to the frame so it can't shift to the
> small one? What else might have changed that I can fix (and how)?
>
It's most likely that the shop has fitted a chainset that needs a longer
bottom bracket axle, but they've used the axle that was already there or
whatever they had handy. If that's the case it's never going to work
properly - take it back and get them to fix it, then find a decent shop
to use in future.

 

[squeaker]

On 22 Dec, 02:03, Rob Morley <[email protected]> wrote:

> It's most likely that the shop has fitted a chainset that needs a longer
> bottom bracket axle, but they've used the axle that was already there or
> whatever they had handy. If that's the case it's never going to work
> properly - take it back and get them to fix it, then find a decent shop
> to use in future.

I suspect that the real problem is that it's 'going to cost you' to
fix it properly (i.e. black chainset to match, and correct chainline)
and the shop went for the cheapest solution to hand - but then screwed
up by not making sure that it worked.
I'm assuming that your original chainset use non-replaceable rings,
hence the complete new chainset, rather than just a replacement inner
ring. A replacement is likely to have replaceable rings: Shimano do
the FC-M341-L (from their website) but they seem to only turn up only
on complete new bikes in the UK. Alternatives are available, e.g.
www.dotbike.com/ProductsP3780.aspx.
As others have said, don't bend anything, just take it back to the
shop and get them to fix it properly - you may well need to discuss
chainset options / cost if you want black (and I don't blame you -
style can be important, at times). And take it for a test ride before
you leave!
Good luck.

 

[Peter Scandrett]

Hi - to all who replied, not just Mark.

Mark T wrote on 21/12/2007 16:05:
> Front mechs are a work of Stan, and will often play up when the chain is
> towards one end of the rear sprockets but work fine when you shift the
> chain towards the other end of the rear sprockets. The shop might have
> checked it was working, but not checked properly.
>
> It is possible that they didn't touch the front mech or cables as most
> shops charge for adjusting the gears. Possibly not good service but then
> I'm not sure what other shops do.

Quick update - I found the time to nip the bike back earlier today and
they readjusted it all in about 10 minutes with no problems/questions
asked. It was a faff to have to do that but hey, these things happen; I
had visions of having to leave it with them but fortunately I didn't
need to.

I asked them what they'd done. They'd adjusted the end stops (again,
since that's what I'd been working with) but also bent the shifter thing
in a bit, as had crossed my mind originally It's reassuring to know
that I was going along the right lines, anyway. It all seems to work OK now.

The guy in the shop said that sometimes these things work on the jig but
not out on the road - which I can understand; I've had that before when
fiddling with things that seem to work fine on the front step, but not
when riding...

Anyway, many thanks to all those who replied. It seems to be working
now, and I've learned a bit more too!

Regards

Peter

PS To answer the person who asked how I'd got it home - I have a
rear-of-car bike carrier which hangs the bike from the top horizontal of
the frame; it was the easiest way of dealing with it when picking it up
after work etc.


--
http://www.scandrett.net/lx/
http://www.scandrett.net/bike/

 

[Rob Morley]

In article <[email protected]>, Peter Scandrett
[email protected] says...
> I asked them what they'd done. They'd adjusted the end stops (again,
> since that's what I'd been working with) but also bent the shifter thing
> in a bit, as had crossed my mind originally It's reassuring to know
> that I was going along the right lines, anyway. It all seems to work OK now.

Did they bend it or just rotate it around the frame tube? If they bent
it they're nasty cowboys (unless they were just correcting existing
damage). The chainset needs to be properly aligned for good chain line,
not just to get the front changer working.

> The guy in the shop said that sometimes these things work on the jig but
> not out on the road
>
They should have road tested it anyway - there's no way you can tell if
brakes or gears will work under load without trying them.

 

[Steph Peters]

Peter Scandrett <[email protected]> of www.scandrett.net wrote:
>I must admit that I'm not terribly impressed with the LBS in question;
>they're OK, I suppose, but nothing to write home about.
You are not the only person I know who has had iffy service from Ken
Fosters. Try Withington Cycles on Burton Road instead.

--
Steph Peters
Chorlton Wanderers Cycling Group
Monthly slow and easy rides from South Manchester
http://www.sandbenders.demon.co.uk/cycling/chwan.htm

 

[naked_draughtsman]

On Dec 23 2007, 2:35 pm, Rob Morley <[email protected]> wrote:
> They should have road tested it anyway - there's no way you can tell if
> brakes or gears will work under load without trying them.

If I've been working on my gears/brakes they always work perfectly in
the 'shop' but needs lots of adjustment after riding around on it.
Unfortunately I don't think I've *ever* found a bike shop who seem to
do this (on one occasion they actually made the problem worse) - hence
I prefer to do this sort of work myself.

peter

 

[Rob Morley]

In article <bcf16e8e-c2d4-4e76-ad1e-
[email protected]>, naked_draughtsman
[email protected] says...
> On Dec 23 2007, 2:35 pm, Rob Morley <[email protected]> wrote:
> > They should have road tested it anyway - there's no way you can tell if
> > brakes or gears will work under load without trying them.
>
> If I've been working on my gears/brakes they always work perfectly in
> the 'shop' but needs lots of adjustment after riding around on it.
> Unfortunately I don't think I've *ever* found a bike shop who seem to
> do this (on one occasion they actually made the problem worse) - hence
> I prefer to do this sort of work myself.
>
When I was a full-time mechanic[[1] I'd never knowingly return a bike to
a paying customer (or consider a PDI complete) without a road test.
It's easier if you have a good hill near the shop, but even without a
hill you can still check performance under load by pedalling and braking
at the same time.

[1] Except at one shop where I worked for a while, where they thought I
was strange for wearing lycra and riding club events, and the stock
consisted of brands like Emmelle and Free Spirit, but I prefer to forget
that episode.

 

[Roger Merriman]

Rob Morley <[email protected]> wrote:

> In article <bcf16e8e-c2d4-4e76-ad1e-
> [email protected]>, naked_draughtsman
> [email protected] says...
> > On Dec 23 2007, 2:35 pm, Rob Morley <[email protected]> wrote:
> > > They should have road tested it anyway - there's no way you can tell if
> > > brakes or gears will work under load without trying them.
> >
> > If I've been working on my gears/brakes they always work perfectly in
> > the 'shop' but needs lots of adjustment after riding around on it.
> > Unfortunately I don't think I've *ever* found a bike shop who seem to
> > do this (on one occasion they actually made the problem worse) - hence
> > I prefer to do this sort of work myself.
> >
> When I was a full-time mechanic[[1] I'd never knowingly return a bike to
> a paying customer (or consider a PDI complete) without a road test.
> It's easier if you have a good hill near the shop, but even without a
> hill you can still check performance under load by pedalling and braking
> at the same time.
>
> [1] Except at one shop where I worked for a while, where they thought I
> was strange for wearing lycra and riding club events, and the stock
> consisted of brands like Emmelle and Free Spirit, but I prefer to forget
> that episode.

yup the local shop to me does that, commented on the noise that the mud
tires made.

roger
--
www.rogermerriman.com

 

[Peter Scandrett]

Steph Peters wrote on 02/01/2008 19:32:
> Peter Scandrett <[email protected]> of www.scandrett.net wrote:
>> I must admit that I'm not terribly impressed with the LBS in question;
>> they're OK, I suppose, but nothing to write home about.
> You are not the only person I know who has had iffy service from Ken
> Fosters. Try Withington Cycles on Burton Road instead.

I thought I'd taken care not to specify which LBS it was...

Perhaps it was slightly 'iffy service' I had but it was resolved in the
end and with due politeness etc so it's not all bad; I've certainly had
far worse service from other shops and stores (not LBSes) that put me
off using them completely; at least in this instance it was sorted
without /too/ much hassle.

Thanks for the recommendation though. If I'm going to take my bike
further that way though in the future somewhere like EBC might be more
convenient. OTOH I might try the bike shop in Urmston again; they were
OK on the one occasion I used them before.

Peter

--
http://www.scandrett.net/lx/
http://www.scandrett.net/bike/

 

[Steph Peters]

Peter Scandrett <[email protected]> of www.scandrett.net wrote:

>Steph Peters wrote on 02/01/2008 19:32:
>> Peter Scandrett <[email protected]> of www.scandrett.net wrote:
>>> I must admit that I'm not terribly impressed with the LBS in question;
>>> they're OK, I suppose, but nothing to write home about.
>> You are not the only person I know who has had iffy service from Ken
>> Fosters. Try Withington Cycles on Burton Road instead.
>
>I thought I'd taken care not to specify which LBS it was...
Easily identifiable by a local. And to me significant because of the other
instances I know of.

>Perhaps it was slightly 'iffy service' I had but it was resolved in the
>end and with due politeness etc so it's not all bad; I've certainly had
>far worse service from other shops and stores (not LBSes) that put me
>off using them completely; at least in this instance it was sorted
>without /too/ much hassle.
That pretty much applies to the other incidents, but it would still be
better if they didn't happen in the first place.
>
>Thanks for the recommendation though. If I'm going to take my bike
>further that way though in the future somewhere like EBC might be more
>convenient. OTOH I might try the bike shop in Urmston again; they were
>OK on the one occasion I used them before.
Haven't used either of those for maintenance. A good experience is the best
recommendation there is.
--
Steph Peters
Chorlton Wanderers Cycling Group
Monthly slow and easy rides from South Manchester
http://www.sandbenders.demon.co.uk/cycling/chwan.htm