Gear Changing Niggle

arlowood

Hi there

Just took delivery of my new Trek Madone 5.9 (2011 model) last Sunday and did my firsty serious ride today of 30 miles. Overall I am mightily impressed with the smoothness of the ride but i experienced an intermittent problem with the gear change. Drivetrain is Ultegra brakes, shifters and 11-28 rear cassette with a Dura Ace compact chainset and Dura Ace rear mech.

Changing down the gears (ie larger to smaller cog) works fine but I did have a problem changing up on one or two occassions. When I flicked the paddle to change up, the lever moved all the way across but did not activate the change (almost like an air-shot at golf). A second waggle of the lever seemed to do the trick in most cases.

It's not a major issue but more of a niggle that the shifting can't be relied on 100%.

Is this something that I can fix by tweaking the barrel adjuster or is it just a symptom of a new set up bedding in and it will get better eventually

arlowood

Hi guys

Apologies. I should have said changing from smaller to larger cog at the start of the second paragraph. It's the changing from larger to smaller cog ie up the gears, where the problem is encountered

Monty Dog

Make of shifters? If the problem is when you go from bigger sprocket to small, then it's usually a sticky cable problem. If it's an upshift failing to engage then it could be down to the shifter - if so, suggest a quick trip to your LBS is worthwhile for further diagnosis.

arlowood

Monty Dog wrote:

Make of shifters? If the problem is when you go from bigger sprocket to small, then it's usually a sticky cable problem. If it's an upshift failing to engage then it could be down to the shifter - if so, suggest a quick trip to your LBS is worthwhile for further diagnosis.

Hi Monty Dog

Ultegra shifters with a Dura Acer rear mech. Problem is when I flick the inner lever to change up the gears ( ie from a larger to a smaller cog) nothing happens. The lever moves across but the rear mech is not activated to move the chain across. A second flick did the trick usually.

Only happened about 3 times on the ride but was still annoying as I have never had the problem with the 105 system on my current bike.

The bike is due to go back for its free service in 3 or 4 weeks time. If the problem is still there I will get them to fix it unless there is a simple remedy that I can implement.

jgsi

Easy enough to re do the rear mech cable adjustment.
YouTube has many a vid.
It sounds like a bit of cable stretch and too much slack when the chain is on the smallest rear cog.
take a few minutes to familiarise yourself with the low and high adjusters and what they do and have a go if you feel confident. The barrel adjuster has probably not enough free play to make a proper adjustment.

fosst

This is probably the same thing that caught me and a few mates out when we got hold of 6700 shifters....
If you catch the outer lever when going for the inner, nothing happens. If your system works fine most of the time and the shifter gives you a "change" where you feel no tension from the cable/mech then I bet that is what is happening.
Worse when wearing gloves?

arlowood

fosst wrote:

This is probably the same thing that caught me and a few mates out when we got hold of 6700 shifters....
If you catch the outer lever when going for the inner, nothing happens. If your system works fine most of the time and the shifter gives you a "change" where you feel no tension from the cable/mech then I bet that is what is happening.
Worse when wearing gloves?

Hi Fosst

Could be what you suggest. Did another 25 miles yesterday and had the same "missed change" problem on several occasions.

I'm wearing fairly thick gloves as you might expect in this weather so I may be catching the outer/brake lever inadvertently when I try to flick the inner paddle. On my next ride I will try to avoid any contact with the outer lever when changing to see if that cures the "air-shot" niggle.

fosst

Try it on a workstand...but trying to make it happen.
It only takes a light touch on the outer to cause this, you will know then if the air shot (better description than mine!) is what we are talking about.
Still sounds like it to me.

arlowood

Just returned from a 30 miler. Glorious crisp sunny day here but a bit chilly in the old foot department by the end.

Anyway, as suggested by Fosst, I was particularly careful when changing up through the gears to avoid touching the brake lever when i activated the inner paddle.

That seemed to do the trick - managed the whole ride with only one "air-shot" and i think that was due to loosing concentration a bit and brushing the brake lever with my gloved finger.

Will keep it under review until the bike goes back for its service in a few weeks time.

My only conclusion is that Ultegra changing mechanism must be extremely sensitive if a brush on the outer lever stops the inner from changing up as it should.