Harsh change back derailleur

[zalle]

Hi guys, I own a full e+ 2018 giant, with a yamaha pro motor, 10 speed xt shadow back derailleur.

I notice that the rear shifter is very harsh when in high power and higher gears. It produces a strong "clunck" and sometimes I even feel the bike shake.

At the shop (over a web chat) they say : " it will clunck as you should not be in a higher gear on the highest level of power. Nor should You be changing gear under load."

Well, I know that, but should it happen?

Any ideas?

 

[anotherkiwi]

They are right, you shouldn't do that.

Yes it should, consumer level derailleurs aren't up to all those Watts coming down the drive train. Don't worry we all do it sometimes - you should try with an unrestricted GSM at full power

 

[zalle]

Errr... What's a GSM? Wikipedia says "GSM (Global System for Mobile communications)"

Anyway, thanks. So I should just be more careful? Thing is I had a Focus Thron, with an eclypse 2 motor, and it always changed very smoothly... It wasn't as powerful though.

I've been told the Focus had a gearchange sensor, and the giant doesn't. Would this be the culprit?

 

[anotherkiwi]

GSM = Chinese mid motor kit sold by Woosh. I rode mine for a while unrestricted and it was quite amusing having a bike that would give a kick of acceleration even in the top gears when at full power.

I think Yamaha might use some kind of gear change sensor similar to the way Bosch do it. But it won't expect you be to changing the top gears at full power I expect.

 

[zalle]

Oh, ok, I know GSM. Thanks for your reply.