Ultegra disk brake lever & caliper question

pete1336

I've just bought my first ever disk brake bike. I've only ever had rim brakes before. My new steed is equipped with ultegra di2.
On all previous rim brake bikes my preference has been to have as little brake lever travel as possible before the caliper engages and pads contact the wheel rim.
When I first rode my new bike I was really surprised at how much lever travel there was before the pads came into contact with the rotor and the bike came to a stop, the lever was practically touching the drops. I know the free stroke can be adjusted a little via the 2mm allen screw under the hood housing but having done this on one of the levers there isnt much difference at all to my mind. There still feels quit a bit of travel before pads engage.
It's a brand new bike and the mechanic at the retailer where I bought it from assured me the brakes where properly bled and set up.
So then, my question is...is there any other adjustment possible which will reduce the lever travel so that the brakes activate earlier? With rim brakes you had fine and course adjustment available at the caliper itself. I take it no such adjustment is available on the R8070?
Thanks in advance.
Peter

david37

no adjustment is available at the calliper on hydraulic disc other tha position on the fork or frame

You could try a mini bleed which is a ten min job. Remove the lever bleed port, add the funnel with some brake fluid in it, squeeze and release the lever. If there is any air it should show as bubbles in the funnell.

Rotate the bars so the funnel is at 45deg repeat until bubbles stop

rotate the other direction by 90deg repeat until bubbles stop

return the funnel to upright and repeat.

This should get any residual air out of the system and also ensure the system is full of fluid.

This should get you to the optimal position. it will never feel the same as very good rim brakes. It's different. I personally prefer the lever feel of rim brakes.

Remember you will need to remove the bleed port again in the future so do not tighten much at all. Or youll damage the head of the screw, or the threads in body or screw, or both. .3 to .5nm. i.e. barely finger tight.

that is about your lot if the brake is new.

once theyre set up they're relatively maintenance free, especially if the bike is used regularly.

pete1336

david37, appreciate your reply. Thanks

wongataa

You could reduce the space between the pads and the disc. You will need the bleed funnel attached and have some brake fluid in it. Carefully pull on the brake levers to advance the pads a little. Take the bleed funnel off and put the bleed port cap back on. Now there will be less space between the pads and disc so the bight point will be sooner.

Downsides are that if there is a little misalignment you will be more likely to get brake rub and you could advance the pads too far quite easily and have to put the bleed funnel back on to capture the extra fluid and press the pistons back into the caliper.

First.Aspect

I don't think this is a good idea. There is minimal clearance anyway.

You will get used to the long lever travel. Pros set up their rim brakes like this anyway because you have better grip strength and feel when your fingers are less extended. Also rather easier to brake from the hoods when the brakes bite with the levers closer to the bar.