Chain won't stay on big ring

[Russell]

Can anyone give me an idea why my chain refuses to stay on the big ring? As soon as I press on the
pedals it pops back to the small ring! The bike is an old Raleigh Rapide road bike.

cheers Russell

 

[kat]

Possibly you need to adjust your front mech. If it is too far over to the left it will not allow the chain to stay on the outer ring. I know what bits to twiddle on a hybrid type bike (the gear cable as it comes out of the shifter) but not sure on a road bike.

 

[Marten Gerritse]

Russell wrote:

> Can anyone give me an idea why my chain refuses to stay on the big ring? As soon as I press on the
> pedals it pops back to the small ring! The bike is an old Raleigh Rapide road bike.
>
> cheers Russell

massive play on the bracket axle? /Marten

 

[Pete Biggs]

Russell wrote:
> Can anyone give me an idea why my chain refuses to stay on the big ring? As soon as I press on the
> pedals it pops back to the small ring! The bike is an old Raleigh Rapide road bike.

I can't remember the Rapide. Has it got a single, double or triple chainset? If not single, make
sure front derailleur is not interfering.

Make sure any chainring bolts are tight, check for bottom bracket play, then check whether the
chainrings are true - may be warped - can sometimes be bent back.

Failing all that, there might be something weirder going on, like an ususual chain angle or wrong
chain tension if the bike has single/hub gears.

~PB

 

[Russell]

Russell <[email protected]> wrote in message news:[email protected]...
> Can anyone give me an idea why my chain refuses to stay on the big ring? As soon as I press on the
> pedals it pops back to the small ring! The bike is an old Raleigh Rapide road bike.
>
> cheers Russell

Thanks for the replies good people I will check out all your ideas tomorrow. Pete B, the bike is a
dinosaur I bought s/h for £20 & only use it for commuting - nobody would ever want to nick it, but I
lock it anyway. Its a
42/52 on the front and 7 coggy things on the back.

cheers Russell

 

[Arthur Clune]

Russell <[email protected]> wrote:

: Thanks for the replies good people I will check out all your ideas tomorrow. Pete B, the bike is a
: dinosaur I bought s/h for £20 & only use it for commuting - nobody would ever want to nick it, but
: I lock it anyway. Its a
: 42/52 on the front and 7 coggy things on the back.

I suspect that the big ring is worn out.

Does it matter though? A 42 on the front is good for 22mph or so - do you really want to go faster
commuting?

Arthur

--
Arthur Clune http://www.clune.org Power is delightful. Absolute power is absolutely delightful -
Lord Lester

 

[Pete Biggs]

Andy Dingley wrote:

>> Can anyone give me an idea why my chain refuses to stay on the big ring?

> Front chainring is worn out.

I can understand this causing the chain to skip under load or to de-rail intermitently but I'd be
surprised if this was the only reason preventing the ring from working at all for a few revolutions.
The wear would have to be incredibly chronic ...but I suppose that could be the case.

~PB

 

[Russell]

Pete Biggs <pLime{remove_fruit}@biggs.tc> wrote in message
news:[email protected]...
> Andy Dingley wrote:
>
> >> Can anyone give me an idea why my chain refuses to stay on the big ring?
>
> > Front chainring is worn out.
>
> I can understand this causing the chain to skip under load or to de-rail intermitently but I'd be
> surprised if this was the only reason preventing the ring from working at all for a few
> revolutions. The wear would have to be incredibly chronic ...but I suppose that could be the case.
>
> ~PB
>
>

I don't *think* its a wear problem although this really is a **** bike we're talking about. I really
havne't had a moment to check anything yet. Its not really that the chain skips off the big ring,
the downtube shifter just moves itself back to the forward position. Before it was too bad it was
quite useful as it would only change down automatically when I hit a steep hill! Now it does it as
soon as I apply any pressure to the pedals.

Russell

 

[Andy Dingley]

On Wed, 16 Apr 2003 18:24:46 +0100, "Pete Biggs" <pLime{remove_fruit}@biggs.tc> wrote:

>I can understand this causing the chain to skip under load or to de-rail intermitently but I'd be
>surprised if this was the only reason preventing the ring from working at all for a few
>revolutions.

Well none of us know really, because we've not seen it.

It's just that whenever I hear "Raleigh" I see visions of shagbat old nails, with chainrings like
sawblades and a chain like Hammersmith Bridge. You probably have to beat the chain with a stick to
make it go round corners, and it rides about halfway up the teeth.

Besides which, all bikes are worn out. It just depends how fussy you are when you look at them.

 

[Pete Biggs]

Russell wrote:
> I don't *think* its a wear problem although this really is a **** bike we're talking about. I
> really havne't had a moment to check anything yet. Its not really that the chain skips off the big
> ring, the downtube shifter just moves itself back to the forward position. Before it was too bad
> it was quite useful as it would only change down automatically when I hit a steep hill! Now it
> does it as soon as I apply any pressure to the pedals.

Gear lever is probably a simple friction type so try increasing the friction by using the ring or
screw on the side. Might also help if front mech is not right on the limit when on the big ring, ie.
with the limit screw, allow it to be shifted out just a touch further than it needs to go.

Also, clean and lubricate the cable guide under the bottom bracket. See:
www.sheldonbrown.com/autoshift.html - This refers to unintentional _up_shifting of the rear gears
but I think the phenomenon could also happen with the front cable (which would of course cause
downshifting).

~PB

 

[Russell]

"Pete Biggs" <pLime{remove_fruit}@biggs.tc> wrote in message
news:<[email protected]>...
> Russell wrote:
> > I don't *think* its a wear problem although this really is a **** bike we're talking about. I
> > really havne't had a moment to check anything yet. Its not really that the chain skips off the
> > big ring, the downtube shifter just moves itself back to the forward position. Before it was too
> > bad it was quite useful as it would only change down automatically when I hit a steep hill! Now
> > it does it as soon as I apply any pressure to the pedals.
>
> Gear lever is probably a simple friction type so try increasing the friction by using the ring or
> screw on the side. Might also help if front mech is not right on the limit when on the big ring,
> ie. with the limit screw, allow it to be shifted out just a touch further than it needs to go.
>
> Also, clean and lubricate the cable guide under the bottom bracket. See:
> www.sheldonbrown.com/autoshift.html - This refers to unintentional _up_shifting of the rear gears
> but I think the phenomenon could also happen with the front cable (which would of course cause
> downshifting).
>
> ~PB

Just went out to look (lunchtime hence Google) and that's fixed it! There's a plastic screw on the
side of the lever which I easily tightened by hand.

Bad news is, I've got a split & bubble in the front tyre (Ultra-gatorskin 25mm) - I was commuting
on my (slightly more) decent race bike last week and had exactly the same thing in a
GP3000$B!r!r!r!r(B. Now can anyone suggest a way of fixing these small sidewall holes? I tried
glueing a piece of inner tube into the GP3000 but it wouldn't stick (with the normal puncture
repair glue).

thanks to everyone for the help! Russell

 

[Call Me Bob]

On 17 Apr 2003 05:02:34 -0700, [email protected] (Russell) wrote:

>Bad news is, I've got a split & bubble in the front tyre (Ultra-gatorskin 25mm) - I was commuting
>on my (slightly more) decent race bike last week and had exactly the same thing in a GP3000????.
>Now can anyone suggest a way of fixing these small sidewall holes?

Don't try, it's not safe. I wouldn't want to ride a tyre in that condition, you're just waiting for
the blow out to happen. If you're going home on it tonight you should (IMHO) keep your speed down
and be very careful.

>tried glueing a piece of inner tube into the GP3000 but it wouldn't stick (with the normal puncture
>repair glue).

You can fix a split temporarily with a tyre boot. Park Tools do them, they are kind of credit card
shaped strips of thin, but tough, plastic. They have adhesive on one side and can be stuck inside
the tyre to stop the innertube forcing its way out and blowing. Just an emergency "get you home"
measure really, not designed as permanent repair.

Bob
--
Mail address is spam trapped To reply by email remove the beverage

 

[Call Me Bob]

On 17 Apr 2003 05:02:34 -0700, [email protected] (Russell) wrote:

>Bad news is, I've got a split & bubble in the front tyre (Ultra-gatorskin 25mm) - I was commuting
>on my (slightly more) decent race bike last week and had exactly the same thing in a GP3000????

Oh yes, just thought, are you sure your brakes are properly aligned with the rim? Sidewall problems
should be quite rare and as you have two split tyres you should check that the blocks (something
else?) aren't catching the tyre under braking. This will very quickly shred a tyre and is
particularly dangerous because the damage occurs when you need your brakes most - a blowout
approaching the corner at the bottom of a fast hill is not what you want (aargh!).

Hold in your brake levers and check exactly where the blocks contact the rim. Also make sure there
is no play in the brake mechanism, this can allow the blocks to move when applied in anger.
Obviously, adjust their positioning if necessary.

Bob
--
Mail address is spam trapped To reply by email remove the beverage

 

[Arthur Clune]

Russell <[email protected]> wrote:

: Bad news is, I've got a split & bubble in the front tyre (Ultra-gatorskin 25mm) - I was commuting
: on my (slightly more) decent

I'd never repair this, except as an emergancy get-me-home. Think about the what happens when your
front tyre fails when you are doing 40mph down a hill. Then think about the dental bills v cost of
a new tyre.

Very small sidewall cuts can be repaired with superglue. Remove the tyre from the rim and put a
small bit of superglue in the cut. Don't bother about smoothing it down or anything (the road will
do that soon enough) but be careful not to get any sharp edges on the inside that will give you
punctures. This is only ok for small cuts though.

Arthur

--
Arthur Clune http://www.clune.org Power is delightful. Absolute power is absolutely delightful -
Lord Lester

 

[Pete Biggs]

Call me Bob wrote:

>> Bad news is, I've got a split & bubble in the front tyre (Ultra-gatorskin 25mm) - I was commuting
>> on my (slightly more) decent race bike last week and had exactly the same thing in a GP3000????
>
> Oh yes, just thought, are you sure your brakes are properly aligned with the rim? Sidewall
> problems should be quite rare and as you have two split tyres you should check that the blocks
> (something else?)

With two different bikes, though. But same brand tyres, and yet again, it's Continental. Conti and
sidewall failures go together like, er, sausage and tomato ...scuse me while I take another bite of
my s&t sandwich .... mmm, niiiice.

Russell, if you do want to ride it home, just stuff anything in there that will stop the tube
bulging out (if it is) - maybe some thick plastic sheeting/bag material - won't necessarily need to
be glued, but try tape.

Ride with low pressure and keep speed very low - especially round the bends.

~PB

 

[Russell]

Arthur Clune <[email protected]> wrote in message news:[email protected]...
> Russell <[email protected]> wrote:
>
> : Bad news is, I've got a split & bubble in the front tyre (Ultra-gatorskin 25mm) - I was
> : commuting on my (slightly more) decent
>
> I'd never repair this, except as an emergancy get-me-home. Think about the what happens when your
> front tyre fails when you are doing 40mph down a hill. Then think about the dental bills v cost of
> a new tyre.
>
> Very small sidewall cuts can be repaired with superglue. Remove the tyre from the rim and put a
> small bit of superglue in the cut. Don't bother about smoothing it down or anything (the road will
> do that soon enough) but be careful not to get any sharp edges on the inside that will give you
> punctures. This is only ok for small cuts though.
>
> Arthur
>
> --
> Arthur Clune http://www.clune.org Power is delightful. Absolute power is absolutely delightful -
> Lord Lester

Don't worry guys, I should have said I didn't ride to work today as I was racing tonight. The bike
was in the back of my car. I will check out the brake alignment on both bikes as I've used
Gatorskins for a couple of years with no problems. This (was) my first set of GP3000's.

Russell