STI shifter question

Garry71

I've just bought my 1st road bike, a Carrera Virtuoso with a 2 ring chainset.
When shifting between rings, it's as if I have to make 2 attempts. Do they use shifters designed for 3 rings?

When I shift from the large ring to the small one, I get a small click on the shifter, and then have to almost force the shifter to get a big click which then moves the chain across.
Is this because the bike is new and stiff, or is it something to tell Halfords about?

Also, when shifting from the small ring to the large one, I have to hold the brake lever across untill the chain moves, instead of the chain moving on the click.

I've never had this type of bike before, so could it be something I'm doing wrong?
Before I spark off another Halfords thread, I have to admit to putting the bike together myself :oops:

Garry

John.T

The short clicks are to trim the front mech to stop chain rub. You need to move the lever full travel to change. Go to the Shimano website and download the tech sheet for your model of shifters. This will tell you how they work and also how to set them up. This might be a good idea if Halfords did it to start with.

fossyant

Yon need to adjust the trim on the mech - it should shift up in one go then you can trim the mech depending upon what sprocket you are using. - I.e play with the adjusters. You don't really want to be tied to a bike shop to maintain your bike.... god help us all !

Now it's best to learn this as it's an essential part of biking. I've always built my bikes up from components - i.e. speced up a frame, had it made for me, ordered wheels, and built it !

Bikes aren't hard to adjust/fix, you just need some mechanical appreciation - all you need to do is move the adjusters in and out to get the best set up.

Garry71

Thanks for the replies.
I've found the relevant docs on the Shimano site, and now understand what's supposed to be happening when operating the controls.
I'll set the front mech adjustments again tomorrow, as the chain sometimes falls off the smaller ring when changing down from the large one. The trim click is probably adding onto the low adjustment I'd already made on the mech assembly.

Thanks again
Garry