apollo bottom bracket and chainset repairs

raisethe said:

I purchase the Alivio chainset 22/32/44 with the appropriate BB un54,
110mm long. These were easy to install but I have had a nightmare
trying to get the gear selection to work. After much fiddling I have
got the front rings to select reasonably, though 2nd maybe dicey, but
I cannot engage the first two gears of the freewheel. I have shortened
the chain by two links, as the previous chasinset was 28/38/48 to take
out some slack. The new bb is 12mm shorter than the old. Otherwise,
everything is the same.

Why can I not get the lowest two gears? Is there anything I can try to
get them to work? Any suggestions would be gratefully received.

I don't know what to suggest without knowing a bit more.....

What happens when you /try/ to shift?

Did you do anything to the rear gear cable?

~PB

Pete Biggs said:

raisethe said:

I purchase the Alivio chainset 22/32/44 with the appropriate BB un54,
110mm long. These were easy to install but I have had a nightmare
trying to get the gear selection to work. After much fiddling I have
got the front rings to select reasonably, though 2nd maybe dicey, but
I cannot engage the first two gears of the freewheel. I have
shortened the chain by two links, as the previous chasinset was
28/38/48 to take out some slack. The new bb is 12mm shorter than the
old. Otherwise, everything is the same.

Why can I not get the lowest two gears? Is there anything I can try
to get them to work? Any suggestions would be gratefully received.

I don't know what to suggest without knowing a bit more.....

What happens when you /try/ to shift?

Did you do anything to the rear gear cable?

Can you also confirm that you mean the two /largest/ sprockets, and your
rear derailleur is the type that's most relaxed in the smallest-sprocket
position?

~PB

Pete Biggs said:

raisethe said:

I purchase the Alivio chainset 22/32/44 with the appropriate BB un54,
110mm long. These were easy to install but I have had a nightmare
trying to get the gear selection to work. After much fiddling I have
got the front rings to select reasonably, though 2nd maybe dicey, but
I cannot engage the first two gears of the freewheel. I have
shortened the chain by two links, as the previous chasinset was
28/38/48 to take out some slack. The new bb is 12mm shorter than the
old. Otherwise, everything is the same.

Why can I not get the lowest two gears? Is there anything I can try
to get them to work? Any suggestions would be gratefully received.

I don't know what to suggest without knowing a bit more.....

What happens when you /try/ to shift?

Did you do anything to the rear gear cable?

Can you also confirm that you mean the two /largest/ sprockets, and your
rear derailleur is the type that's most relaxed in the smallest-sprocket
position?

~PB

raisethe said:

raisethe said:

Nigel Cliffe said:

> --
Nigel Cliffe,
Webmaster athttp://www.2mm.org.uk/

Thanks Nigel, I'll report back when I've bought and assembled the
bits.- Hide quoted text -

- Show quoted text -

I purchase the Alivio chainset 22/32/44 with the appropriate BB un54,
110mm long. These were easy to install but I have had a nightmare
trying to get the gear selection to work. After much fiddling I have
got the front rings to select reasonably, though 2nd maybe dicey, but
I cannot engage the first two gears of the freewheel. I have shortened
the chain by two links, as the previous chasinset was 28/38/48 to take
out some slack. The new bb is 12mm shorter than the old. Otherwise,
everything is the same.

Fear that 12mm might be significant. Previous post said +/- 0.5mm didn't
matter.

122mm BB's are pretty common for triple chainsets. I'd be tempted to do a
trial assembly on the old BB (even if its shot) to see if the mechanisms
then run OK.

Quoted message said:

Why can I not get the lowest two gears? Is there anything I can try to
get them to work? Any suggestions would be gratefully received.

As others have said, can you be more specific.

Is it the inner most two cogs at the rear (the big sprockets) ?
Does it happen in all front gears, or only some ? Assuming you disturbed
nothing at the back, even with the different bottom bracket, the rear should
still work fine on the middle and larger cogs.

- Nigel

--
Nigel Cliffe,
Webmaster at http://www.2mm.org.uk/

raisethe said:

raisethe said:

Nigel Cliffe said:

> --
Nigel Cliffe,
Webmaster athttp://www.2mm.org.uk/

Thanks Nigel, I'll report back when I've bought and assembled the
bits.- Hide quoted text -

- Show quoted text -

I purchase the Alivio chainset 22/32/44 with the appropriate BB un54,
110mm long. These were easy to install but I have had a nightmare
trying to get the gear selection to work. After much fiddling I have
got the front rings to select reasonably, though 2nd maybe dicey, but
I cannot engage the first two gears of the freewheel. I have shortened
the chain by two links, as the previous chasinset was 28/38/48 to take
out some slack. The new bb is 12mm shorter than the old. Otherwise,
everything is the same.

Fear that 12mm might be significant. Previous post said +/- 0.5mm didn't
matter.

122mm BB's are pretty common for triple chainsets. I'd be tempted to do a
trial assembly on the old BB (even if its shot) to see if the mechanisms
then run OK.

Quoted message said:

Why can I not get the lowest two gears? Is there anything I can try to
get them to work? Any suggestions would be gratefully received.

As others have said, can you be more specific.

Is it the inner most two cogs at the rear (the big sprockets) ?
Does it happen in all front gears, or only some ? Assuming you disturbed
nothing at the back, even with the different bottom bracket, the rear should
still work fine on the middle and larger cogs.

- Nigel

--
Nigel Cliffe,
Webmaster at http://www.2mm.org.uk/

Nigel Cliffe said:

Quoted message said:

I purchase the Alivio chainset 22/32/44 with the appropriate BB un54,
110mm long. These were easy to install but I have had a nightmare
trying to get the gear selection to work. After much fiddling I have
got the front rings to select reasonably, though 2nd maybe dicey, but
I cannot engage the first two gears of the freewheel. I have
shortened the chain by two links, as the previous chasinset was
28/38/48 to take out some slack. The new bb is 12mm shorter than the
old. Otherwise, everything is the same.

Fear that 12mm might be significant. Previous post said +/- 0.5mm
didn't matter.

122mm BB's are pretty common for triple chainsets. I'd be tempted
to do a trial assembly on the old BB (even if its shot) to see if the
mechanisms then run OK.

Let's be specific. What axle length does Shimano recommend for the Alivio
chainset?

~PB

Nigel Cliffe said:

Quoted message said:

I purchase the Alivio chainset 22/32/44 with the appropriate BB un54,
110mm long. These were easy to install but I have had a nightmare
trying to get the gear selection to work. After much fiddling I have
got the front rings to select reasonably, though 2nd maybe dicey, but
I cannot engage the first two gears of the freewheel. I have
shortened the chain by two links, as the previous chasinset was
28/38/48 to take out some slack. The new bb is 12mm shorter than the
old. Otherwise, everything is the same.

Fear that 12mm might be significant. Previous post said +/- 0.5mm
didn't matter.

122mm BB's are pretty common for triple chainsets. I'd be tempted
to do a trial assembly on the old BB (even if its shot) to see if the
mechanisms then run OK.

Let's be specific. What axle length does Shimano recommend for the Alivio
chainset?

~PB

Pete Biggs said:

Quoted message said:

Quoted message said:

Why can I not get the lowest two gears? Is there anything I can try to

get them to work? Any suggestions would be gratefully received.

Many thanks for the responses.

Quoted message said:

I don't know what to suggest without knowing a bit more.....

What happens when you /try/ to shift?

The indexing is two gears out. So when I am in first gear it is on the
3rd cog, 2nd is the 4th cog and so on. Originally, when I put it in
6th or 7th gear, the chain fell off to the right, but I have managed
to adjust this, so that it stays on the 7th (smallest) cog for 5th,
6th and 7th gears.

Quoted message said:

Did you do anything to the rear gear cable?

Not to start with, but when desperation set in I released it and tried
it a bit tighter and a bit looser. It didn't help though.

Pete Biggs said:

Quoted message said:

Can you also confirm that you mean the two /largest/ sprockets,

Yes, the largest has 34t and the 2nd has 24t. If it was only the
megarange that I couldn't get, I would have changed the freewheel, but
it can't get rthe 24t sprocket either.

and your

Quoted message said:

rear derailleur is the type that's most relaxed in the smallest-sprocket
position?

I don't know. How could I find that out?

Nigel Cliffe said:

The new bb is 12mm shorter than the old. Otherwise,

Quoted message said:

everything is the same.

Fear that 12mm might be significant. Previous post said +/- 0.5mm didn't
matter.

BoB recommended the shorter one.

http://tinyurl.com/3ymarq

The problem seems to be that the chainset is too far to the right, the
shorter bb tells me that it is too the left of the old one. This seems
strange to my non mechanical mind.

Quoted message said:

122mm BB's are pretty common for triple chainsets. I'd be tempted to do a
trial assembly on the old BB (even if its shot) to see if the mechanisms
then run OK.

Quoted message said:

Why can I not get the lowest two gears? Is there anything I can try to
get them to work? Any suggestions would be gratefully received.

As others have said, can you be more specific.

Is it the inner most two cogs at the rear (the big sprockets) ?

yes

Quoted message said:

Does it happen in all front gears, or only some ?

It happens as explained to Pete above on the smallest and largest
front ring. The second ring is scraping on the derailleur cage, and
the problem is worse by another gear, ie it is 3 gears out of line and
doesn't engage so well with them.

Assuming you disturbed

Quoted message said:

nothing at the back, even with the different bottom bracket, the rear should
still work fine on the middle and larger cogs.

Yes it does. The rear cogs that engage, engage well for the smallest
and largest front rings.

Quoted message said:

Pete Biggs said:

Nigel Cliffe said:

Quoted message said:

I purchase the Alivio chainset 22/32/44 with the appropriate BB un54,
110mm long. These were easy to install but I have had a nightmare
trying to get the gear selection to work. After much fiddling I have
got the front rings to select reasonably, though 2nd maybe dicey, but
I cannot engage the first two gears of the freewheel. I have
shortened the chain by two links, as the previous chasinset was
28/38/48 to take out some slack. The new bb is 12mm shorter than the
old. Otherwise, everything is the same.

Quoted message said:

Fear that 12mm might be significant. Previous post said +/- 0.5mm
didn't matter.

Quoted message said:

122mm BB's are pretty common for triple chainsets. I'd be tempted
to do a trial assembly on the old BB (even if its shot) to see if the
mechanisms then run OK.

Let's be specific. What axle length does Shimano recommend for the Alivio
chainset?

~PB- Hide quoted text -

- Show quoted text -

Here it is.

http://tinyurl.com/2qao4n

http://tinyurl.com/3bgnbp

But the compatability chart below shows neither my chainset or bb.

http://tinyurl.com/2obhnc

I am getting a bit out of my depth here, so would be interested to
know if you think my bits are not compatable.

In article <[email hidden]>,
raisethe
[email hidden] says...

Quoted message said:

I am getting a bit out of my depth here, so would be interested to
know if you think my bits are not compatable.

Put the chain on the middle chainring and middle sprocket, and sight
along the chain from the front of the bike - does it appear to deviate
sideways where it meets the ring and sprocket?

Rgeardless of whether it does, you may be able to get everything working
OK - while a perfect chainline is desirable it's not essential.

In article <[email hidden]>,
raisethe
[email hidden] says...

Quoted message said:

The indexing is two gears out. So when I am in first gear it is on the
3rd cog, 2nd is the 4th cog and so on. Originally, when I put it in
6th or 7th gear, the chain fell off to the right, but I have managed
to adjust this, so that it stays on the 7th (smallest) cog for 5th,
6th and 7th gears.

There are two common reasons that a rear mech suddenly starts displaying
these tendencies - either the mech is bent, or the cable or its casing
have moved in one of their locating points. Try this:

Hang the bike up so you can rotate the crank with one hand and have a
hand free.
Put the chain on the middle ring.
Undo the clamp holding the rear mech cable and tuck the cable out of the
way somewhere.
Now 'pedal' with your right hand while pushing the rear mech inwards -
rest a couple of fingers on the chainstay, and press your thumb on the
bottom of the parallelogram (not the cage), and let it spring out again.
Does it have a full range of movemement, or does it refuse to go into
some gears or jump off the inside or outside?
If it's not covering the full range check that the limit adjuster screws
aren't screwed in too far - if they're both screwed in about the same
amount and the underside of the head is about flush with the derailleur
body (typically, depending on the mech) then there's likely to be a
problem with the derailleur alignment.
If the above doesn't reveal any problems then it's a cable/lever
problem. Make sure the cable is properly seated and routed, starting
with the nipple and working down to the rear mech. Screw the barrel
adjuster(s) all the way in, and clamp the cable to the mech, making sure
you get it on the correct side of the clamping arrangement and that
there's minimal slack with the chain on the smallest sprocket. Now try
running through the gears with the chain on the middle ring.

raisethe said:

Pete Biggs said:

Quoted message said:

> Why can I not get the lowest two gears? Is there anything I can
> try to
get them to work? Any suggestions would be gratefully received.

Many thanks for the responses.

Quoted message said:

I don't know what to suggest without knowing a bit more.....

What happens when you /try/ to shift?

The indexing is two gears out. So when I am in first gear it is on the
3rd cog, 2nd is the 4th cog and so on. Originally, when I put it in
6th or 7th gear, the chain fell off to the right, but I have managed
to adjust this, so that it stays on the 7th (smallest) cog for 5th,
6th and 7th gears.

Just checking - you haven't had the axle out of the rear wheel ? (eg. to
clean/lube the bearings)
I've done that (taking huge care not to move one cone) and put the axle back
the wrong way round (including swapping the spacers round) and found the
wheel moved over in the frame by significant margin. Put axle back the
correct way, and all was fine.

As others have said, need to get to bottom of why rear mech doesn't work
correctly. This is unlikely to be directly related to front chainset issues.

Back to the front end; my reading of the specs is that you have a sane
Bottom Bracket for the crankset. It says 113mm for 50mm offset from centre
line. 110mm is close enough (only 1.5mm difference each side). So, if
chainset doesn't foul everything, should be OK once adjusted correctly.
Double check this with Rob Morley's recommendation of putting bike into
middle-middle gear and look at chain along its top edge. Does it look
straight and parallel to axis of bike ? Should be near enough straight
(small deviation doesn't matter).

If the front mechanism is fouling things, it needs adjusting; possibly down
(slide down seat tube), check it is truely parallel to the bike. The
mechanism should show about 2mm clear of the outer chainring as the
mechanism swings out past the edge of the teeth. Finally adjust cable
pull.

Next slowly setup the rear gears.

Start by carefully checking cable run to rear gears; its not been
dislodged/kinked in all the repairs ?
Then work through from basics.
- Look carefully at rear derailleur - it is parallel and vertical (not been
bent).
- Disconnect rear gear cable. Check movement of rear mechanism by hand, it
should "spring" automatically to the smallest sprocket. By pushing on the
parallelogram you should be able to make it reach the largest sprocket. If
not, adjust the stop-limit screws on the rear mechanism (there are two, one
for small sprocket, one for large).
- Now connect gear cable. Set the "twiddling" adjusters a fraction above
"fully in". The gear cable it should be just taught when in highest gear
number (smallest sprocket) on shifter.
- Carefully study how the gear shifts, does it climb up each gear correctly
? If not, twiddle adjuster to be a little tighter (adjuster screws out of
housing). Check shifts down to smaller, again, if not shifting, twiddle
adjuster in a fraction. Twiddle carefully, quarter turns and count what
you are doing until you can do it instinctively.
- bike should now change reliably at rear with all sprockets.

- Nigel

--
Nigel Cliffe,
Webmaster at http://www.2mm.org.uk/

raisethe said:

The indexing is two gears out. So when I am in first gear it is on the
3rd cog, 2nd is the 4th cog and so on. Originally, when I put it in
6th or 7th gear, the chain fell off to the right, but I have managed
to adjust this, so that it stays on the 7th (smallest) cog for 5th,
6th and 7th gears.

Quoted message said:

Did you do anything to the rear gear cable?

Not to start with, but when desperation set in I released it and tried
it a bit tighter and a bit looser. It didn't help though.

I would "start again" with the cable. Detatch cable, check cable is ok or
get a new one, put the shifter in top-gear position, attach and tension*
cable, try the gears, adjust cable tension to fine tune the indexing.

If still no joy then I might suspect the derailleur or something is
knackered or badly aligned.

More instructions and tips:
http://www.sheldonbrown.com/derailer-adjustment.html

* Before attaching cable, screw in cable adjuster on derailleur all the way,
and cable adjuster on front of bike (if any) half way. Attach cable then
turn cable adjuster on derailleur anti-clockwise until cable is reasonably
taut. Then try shifting and adjust cable tension as necessary to get the
indexing right.

~PB

raisethe said:

Nigel Cliffe said:

The new bb is 12mm shorter than the old. Otherwise,

Quoted message said:

everything is the same.

Fear that 12mm might be significant. Previous post said +/- 0.5mm
didn't matter.

The difference in BB length is irrelevant if the crank is designed for it.
See my comment below.

Quoted message said:

BoB recommended the shorter one.

http://tinyurl.com/3ymarq

The problem seems to be that the chainset is too far to the right, the
shorter bb tells me that it is too the left of the old one. This seems
strange to my non mechanical mind.

Different cranks have different shapes and can require different BBs to
provide the same chainline on the same bike. So required BB length is very
much dependent on make and model of crankset.

So far I think you've probably got the correct combination.

~PB

raisethe said:

Quoted message said:

rear derailleur is the type that's most relaxed in the
smallest-sprocket position?

I don't know. How could I find that out?

By releasing the cable and seeing which position the derailleur rests in.
But it's probably not relevant so don't worry about it for now.

~PB

Rob Morley said:

In> Put the chain on the middle chainring and middle sprocket, and sight
along the chain from the front of the bike - does it appear to deviate
sideways where it meets the ring and sprocket?

No it doesn't. It deviates to the right (looking from the front)
though where it is deflected by the cage.

raisethe said:

Rob Morley said:

In> Put the chain on the middle chainring and middle sprocket, and
sight along the chain from the front of the bike - does it appear to
deviate sideways where it meets the ring and sprocket?

No it doesn't. It deviates to the right (looking from the front)
though where it is deflected by the cage.

Tweak/pull the front cage so that doesn't touch and look again. This
observation is trying to establish if the middle chain ring is in line with
the middle rear sprocket *without* any of the gear shifting bits
touching/pulling anything. That will confirm that the bottom bracket is
about the right length.

--
Nigel Cliffe,
Webmaster at http://www.2mm.org.uk/

In article <[email hidden]>, Nigel Cliffe
[email hidden] says...

Quoted message said:

Tweak/pull the front cage so that doesn't touch and look again. This
observation is trying to establish if the middle chain ring is in line with
the middle rear sprocket *without* any of the gear shifting bits
touching/pulling anything. That will confirm that the bottom bracket is
about the right length.

As long as the rear triangle isn't out of track. :-)