Mysterious shifting problem new bike.

[Kbrook]

3 weeks old, bought online so no option to take it back to the shop, plus I like to sort issues out myself, or with the help of Cycle chatters.

Shimano 105 R7000 hyraullic group set with the exception of a non series RS510 chainset. Wont shift from small to big chainring at all under load(going uphill) and takes several revolutions to change from big to small under load. I’ve adjusted the cable tension to death and all I can achieve is to get it to shift both ways if I stop pedalling for a second.
I’ve had group sets from Claris to Ultegra and never encountered this issue and it’s got me puzzled. I can live with it but it’s just annoying. Anybody had a similar problem or can suggest what the issue might be.
Ive even changed the front derailleur from the one that came on the bike to one I know is ok, it does exactly the same with both.

 

[Sharky]

Wont shift from small to big chainring at all under load(going uphill)

Don't recall if I have ever done that!

 

[SpokeyDokey]

3 weeks old, bought online so no option to take it back to the shop, plus I like to sort issues out myself, or with the help of Cycle chatters.

Shimano 105 R7000 hyraullic group set with the exception of a non series RS510 chainset. Wont shift from small to big chainring at all under load(going uphill) and takes several revolutions to change from big to small under load. I’ve adjusted the cable tension to death and all I can achieve is to get it to shift both ways if I stop pedalling for a second.
I’ve had group sets from Claris to Ultegra and never encountered this issue and it’s got me puzzled. I can live with it but it’s just annoying. Anybody had a similar problem or can suggest what the issue might be.
Ive even changed the front derailleur from the one that came on the bike to one I know is ok, it does exactly the same with both.

R7000 FD is a nasty thing to adjust.

Trek US said that they were a PITA to set-up plus my supplying dealer couldn't get it right (and nor could I) so it was swapped out for the last of the pre-R7000 105 series - much better.

 

[Kbrook]

Don't recall if I have ever done that!

I know it’s not normal but I’ve never had a problem before

 

[Kbrook]

R7000 FD is a nasty thing to adjust.

Trek US said that they were a PITA to set-up plus my supplying dealer couldn't get it right (and nor could I) so it was swapped out for the last of the pre-R7000 105 series - much better.

They are a pain so I’ve swapped mine out for a Dura ace 9000, which I know is ok

 

[fossyant]

Upper limit screw, let it over shift a little to pop the chain on the big ring !

 

[Kbrook]

I wonder if the non series chainset may be an issue

 

[fossyant]

I wonder if the non series chainset may be an issue

Nope.

Front Mech adjustment

 

[T4tomo]

I wonder if the non series chainset may be an issue

there is no reason why it should be assuming its a standard double or compact. if you have something mad like e.g. 52-30 the bigger jump might be causing an issue. its still a Shimano road series chainset

 

[Kbrook]

I was only suggesting chainset as I’ve tried everything else. Im confident the front mech has been set up exactly as per Shimanos instructions. I shall give it another look at though.

 

[T4tomo]

sometime just slackening the cable off and starting again from scratch with the limit screws can work, rather than micro adjusting everything.

 

[fossyant]

. Im confident the front mech has been set up exactly as per Shimanos instructions.

We're not !

 

[SpokeyDokey]

Maybe someone who has successfully set up an R7000 Fd will be along to chime in.

I tried and it is a right B.

Shimano trying to solve a problem that on most bikes doesn't exist ie long arm clearance issue. Even with 35mm tyres on my long arm 105 has decent clearance.

 

[Dogtrousers]

I'd love to give some useful advice, but unfortunately when I set my R7000 front mech up, everything worked OK. It's fine. And looking at the thread above you've probably done all the things I'd suggest. My approach is just to twiddle randomly with random adjusters until it works.

 

[Roseland triker]

Too much cable tension and not enough over shift available for the mech.
Also shifting up under load is poor gear changing,build up speed and let the chainset spin without load during shifting...