Help please-Jockey wheel/cassette touching!

[Oldbloke]

Hi all & Happy New Year

I need some expert advice please...

I ride a Spesh Roubaix Elite, bought it used off e-Bay a year ago.

It's got the standard spec for this model, 105 r/mech with a 11-28 SRAM cassette.

To minimize contact between the upper jockey wheel & 28T cog, the "B" screw has been screwed in to it's limit, but the rubbing has got worse during past year (ridden 3k kms)

I've tried shortening the chain with minimal success; not sure what else I should do; is it a case of changing to a longer cage and/ or to a 27T maximum gear cassette?

Hope this makes sense...

All advice gratefully recieved

Terry

 

[youngoldbloke]

You might find some useful information here sheldon brown b screw - especially re. adjusting the b screw

 

[screenman]

You did 3,000 kms last year I take it the chain has been changed. When it was changed did you check the new one for length.The mech still sounds like it requires adjustment.

 

[Oldbloke]

I tried putting a longer B screw in but the increased angle to the stop meant the end of the screw slips off the stop.

Didn't occur to me to put the screw in the other way as per Sheldon, I'll try that

Changed the chain at which point I tried reducing by one link, very slight improvement. Am now about to change to an Ultegra chain to see if that helps, (fingers crossed!)

 

[fossyant]

Did you ever feel the need to get a longer chain............ faffing about with the B screw won't help. Get a new chain, and start with 4 more links.

Then go to 2 more if it works (easier to remove than add).

The chain is being pulled too tight, so get a longer chain.

Also check. Big Chain ring (front) and small sprocket (at rear wheel) both jockey's (on the mech) should be one on top of other........ at 90 degrees to road.

 

[gbb]

Thinking about it logically (IMLE) the manufacturer wouldnt have put a bike out with such close tolerances. Has something changed in the bikes lifetime or is something bent.
Hanger ? any sign of damage or bending ?
Has the chain been changed in the past and had a shorter chain incorrectly fitted (this would tie in with Fossys observation, trying a longer chain)
If its had a short chain fitted, does that force the previous owner to have the wheel further forward in the dropouts than would be normal, bringing it into conflict with the jockeywheels. Not sure if thats possible even, but just a thought.

 

[fossyant]

gbb, the bike was bike bought second hand, and even I do not trust bike shops...........

 

[Oldbloke]

Did you ever feel the need to get a longer chain............ faffing about with the B screw won't help. Get a new chain, and start with 4 more links.

Then go to 2 more if it works (easier to remove than add).

The chain is being pulled too tight, so get a longer chain.

Also check. Big Chain ring (front) and small sprocket (at rear wheel) both jockey's (on the mech) should be one on top of other........ at 90 degrees to road.

 

[Oldbloke]

OK thanks, I'll give this a try tomorrow.

When I last changed the chain, I measured the new against the old. I then measured as per Sheldon, ie, largest cogs front & rear then add 1 link; this was longer than the original & allowed the mech to move closer to the cassette.

 

[Oldbloke]

Thinking about it logically (IMLE) the manufacturer wouldnt have put a bike out with such close tolerances. Has something changed in the bikes lifetime or is something bent.
Hanger ? any sign of damage or bending ?
Has the chain been changed in the past and had a shorter chain incorrectly fitted (this would tie in with Fossys observation, trying a longer chain)
If its had a short chain fitted, does that force the previous owner to have the wheel further forward in the dropouts than would be normal, bringing it into conflict with the jockeywheels. Not sure if thats possible even, but just a thought.

 

[Oldbloke]

ok thanks for replying.

The hanger looks straight and not abused; I don't think there's any room for movement in the dropouts.

I'll try Fossy's suggestion tomorrow, I've run out of linkpins today!

 

[Oldbloke]

gbb, the bike was bike bought second hand, and even I do not trust bike shops...........

 

[Oldbloke]

and never again will I buy a bike unseen off e-Bay, bloke had good feedback etc but gave pack of lies in description. Due to long delay in delivery due to bad weather & him vamoosing out of the UK, I had no recourse.

An expensive lesson learnt there