Never done this before, is it as “simple” as explained here?
http://www.epicbleedsolutions.com/blog/shorten-shimano-hoses-without-bleeding/

I have the olives, barbs, and yellow hose clamp.

Measure twice, cut once and away I go?

In theory it is that easy.

I had an issue inserting the connector insert.

Net result I need to now bleed both brakes 😳

Thanks, I’ll have no issues taking to the LBS if things go wrong, but its a new skill I’d like to learn, followed most likely by bleeding brakes.

It is really incredibly simple. One of the highest differences between expected complication and actual ease of any bike job there is. The hardest part is tapping in the new insert into the cut hose. I grip the hose with pliers and tap it in with a hammer, probably not textbook but I haven’t died yet!

Way to go with expectation management there flatboy! 😀

The hardest part is tapping in the new insert into the cut hose.

this, I had a nightmare with one, at this point you cant just put it all back together again and take it to the LBS so I ended up with oil everywhere*. But a rebleed sorted it all out

*I can be cack-handed at times

I had a few Shimano brakes to do and decided to invest in a Jagwire needle driver and one of their hose cutters. Takes out all the faffing with a hammer, ensures a clean cut, and avoids issues such as those experienced by letmetalktomark. Of course it’s possible to do the job without these tools but they do remove plenty of the risk of things going wrong if you are a bit heavy/cack-handed like me. Needle driver is About £19 from Amazon* and cutter is £11.

I followed the Epic instructions closely using one of their bleed kits (hose, syringes and Shimano fluid) and it went okay.

Review of both Jagwire tools here: http://www.bikerumor.com/2012/01/05/review-ja/ .
Video of needle driver in action: https://www.youtube.com/watch?v=-030kPzvwJE

*other vendors are of course available…

I’ve shortened plenty of Shimano brake hoses without the need for bleeding afterwards. However, in a number of cases, if the bike had been upside down for any length of time, and then righted, the levers would need a load of pumping before they would firm up again (oo-er).

To eliminate this they needed a bleed-lite. ie Fit the bleed funnel on the lever, put some fluid in, gently depress the lever a few times, doing this with the lever level, then tipped forward and then tipped backwards. This eliminated any small amounts of air that entered during the cutting process.

For fitting the barb I’ve found that putting the hose in the yellow ‘clamp’, clamping that lot with a small vice (actually the G-clamp from a desk swivel-lamp) and a tap with a pinning hammer works well.

Apart from the mildly tricky tapping, all you’re doing is undoing a nut, cutting something and tightening the nut back up. It’s no harder than shortening a gear cable.

Is there a way to block the end of the hose if you need to feed it through your frame before cutting to size to stop the fluid leaking out so you can just do a top up instead of a full bleed or is that just wishful thinking? (presuming you bought them already bled i.e. a sealed unit)

I followed that exact guide over the weekend with no issues and didn’t need to bleed after. The one thing I found was the barb needed quite a bit of force to get it in and the hose slipped in the yellow clamp box, gave it a quick wipe and all was fine.

I find a pair of mole grips quite satisfactory to hold the yellow blocks with the hose in. You really aren’t tapping hard with the hammer, so it’s fine for me…

I’d agree that in every case so far while the brake may have been usable it’s wanted a rebleed to be perfect again though.

Yeah it was quite simple, I managed to get the rear barb in fine, but bugger up the front one. Probably take it to the LBS and get them to do it, but it was a useful learning experience.