Bicycle Mechanics - Shimano Shifting Problem

I have a Shimano 105 triple set-up on a steel road bike.

It is 5 years old with about a total of 8000 miles.

Recently I cannot seem to be able to set it up right.

When I get a sweet change going up the gears it is tardy coming down. I then adjust to get going down right then the tardiness changes to going up.

I replace my change regularily and recently fitted a new Shimano Ultegra rear derailleur and a new Shimano middle chain ring as I use the middle ring 80% of the time.

This did not cure the problem.

Where do I go from here . Replace the cassette? It has 8000 miles on it (the same as the rest of the parts).

Replace the changers ? - (very expensive).

All suggestions gratefully received (please dont say change to Campag)

Have you checked that the RD hanger is square to the wheel?

More than likely you need new shift cables and cable housings. Always replace the housings when replacing the cables. Also try squirting copious quantities of WD40 into the shifter internal mechanisms.

Al

It really doesn't sound like a shifter problem. It sounds like the rear setup has a bias, as it would with a bent hanger, where the chain "wants" to move in a certain direction. You can counteract that with the barrel adjuster, but then the RD will be too far in the other direction and it will eventually move the chain. So my bet's on the hanger alignment.

But you could be right about the housing. 8000 mi on a housing is a lot. Offsetting a slow housing with the RD would have a similar effect to counteracting a bent hanger.

It really doesn't sound like a shifter problem. It sounds like the rear setup has a bias, as it would with a bent hanger, where the chain "wants" to move in a certain direction. You can counteract that with the barrel adjuster, but then the RD will be too far in the other direction and it will eventually move the chain. So my bet's on the hanger alignment.

But you could be right about the housing. 8000 mi on a housing is a lot. Offsetting a slow housing with the RD would have a similar effect to counteracting a bent hanger.

Yeah, you could be right.

RD hanger is square and new cables fitted recently.
Dont understand housing do you mean shifters?

RD hanger is square and new cables fitted recently.
Dont understand housing do you mean shifters?

Housing is the tubing that the cables run through. Dirt, water, and corrosion crude builds up inside the housings and causes excess friction. The excess friction ******* the derailleur function, especially when the cable is released from the shifter and pulled by the derailleur spring. The housings should always be replaced when the cables are replaced. The short housing just before the rear derailleur is especially vulnerable to dirt and water spray.

Al

+1 on housing replacement. ALWAYS replace housing and cable together. Roughly 90% of shifting issues are caused by cable/housing issues including correct routing.