FITTING BRAIDED BRAKE HOSES
Get more feel!
As we’ve covered in the brake servicing section, your brakes are vital to a safe and enjoyable ride.
Ensuring all the components in the system are in good fettle gives them the best chance of performing to their optimum and boosting your confidence. Going a little hot into a corner and not having the faith in your brakes can end badly.
Braided brake lines don’t make your brakes any ‘better’ but what they do do is make them (fractionally) more efficient, more predictable and they give more ‘feel’. As a bit of an extra bonus they also have a longer service life than stock, rubber hoses.
Rubber hoses can, over time start to perish and bulge as the brakes are applied (the more force you apply the more they can bulge).
This bulging gives you a bit more ‘squish’ in the feel at the lever and means the pressure the fluid exerts is not being directed entirely to the brake pistons - some effort is being expended into the walls of the hoses.
Braided lines have a more rigid sidewall in the form of a braided ‘sheath’ around the hose that resists this bulging, resulting in a more solid and consistent feel at the brake lever. They also tend to have stainless or zinc coated fittings (called banjos) at the end of the hose which resist corrosion.
How To Fit them
In order to replace stock brake lines with braided lines you’ll need to disconnect them from the system, this means you’re going to lose fluid and introduce air into the lines, so you will need to bleed the system once you’re done.
It would be our recommendation that you look to replace your brake lines at the same time as overhauling calipers and /or upgrading a master cylinder, as you’ll be opening the system up.
Remember brake fluid is nasty stuff – Wear gloves and don’t let it drip on your paintwork. It’ll eat through it in no time.
What you’ll need:
- New braided lines, specifically for your bike - most manufacturers have all the measurements for pretty much every model out there. They should come with new copper washers - if not, you’ll need to get these too.
- A decent socket and spanner set – you’ll mainly be using a 13mm socket, for the banjo bolts and a 11,10,9 or 8mm ring spanner for the bleed nipples (depending on your specific bike)
- A low range torque wrench
- Fresh brake fluid (Check the quantity and kind your bike needs and remember never to mix DOT5 fluid with other varieties – they aren’t compatible)
- A brake bleeder -various types are available – a simple piece of the right diameter hose works in a pinch, BUT you’ll make life a lot easier for yourself if you get a ‘one-man’ kit or preferably a vacuum bleeder. These can be had for as little at £15.
- You can also use a syringe to ‘push’ and ‘pull’ fluid into the system if you get a stubbon airlock
- Mechanics gloves and plenty of ‘blue roll’ for wiping up any spilt fluid
- A mug of tea!
The following guidance refers to the front brake set up, but the theory is the same for rear brakes.
Ok, let’s get cracking.
To start get your bike on level ground.
Open your front brake master cylinder fluid reservoir and, if you’ve got a syringe, suck out as much of the fluid from the reservoir as you can. Remember to dispose of old fluid correctly. It’s nasty stuff.
Now move down the brake lines to the calipers. Where the lines join caliper(s) undo the banjo bolt. Remember this will be difficult to undo if you’ve removed the calipers from the forks so do this before unbolting the calipers, if you’re planning to overhaul them at the same time.
At this point fluid will start to weep out so have some blue roll to hand and, once you’ve removed the bolt, point the end of the line into a container to catch any remaining fluid as it runs out of the line.
Do the same on the other side.
Now move back up the lines and undo the banjo bolt where the lines join the master cylinder, again there will be some fluid seepage here so have some blue roll to hand.
Now the lines are disconnected, remove them from the bike – you may have to undo various fixings/clips to get them free.
Installation is the reverse, but make sure you use new copper washers either side of the hose banjos.
Torque all banjo bolts up to the manufacturer specified torque.
Now it’s time to put the fresh fluid in and bleed the system. Top up the reservoir and then, starting with the caliper furthest from the master cylinder, attach your brake bleeder to the bleed nipple on the caliper and apply vacuum (or pump the brake lever, slowly, opening and closing the brake bleed nipple each time you pump the lever - opening as you squeeze, hold once the lever is fully in and then close the bleed nipple before releasing the lever - and repeat)
Bleeding brakes can be very frustrating and time consuming if you get a stubborn air lock. Keep going and after 30 or so strokes on one caliper, lock the nipple off and switch to the other side and repeat. After some time you should expel all the air from the system and find you get the firm feel back in the lever.
You master cylinder may also have its own bleed nipple. If it does, also bleed the system here. If not then you have 2 further options.
- You can either replace the banjo bolt with a new one that has an integrated bleed nipple -most braided brake line manufacturers can supply these, or
- If not then you can do it by loosening and re tightening the ‘seal’ at the banjo bolt as you pump the lever until you can see that fluid is being pushed past the copper washers, then nip the bolt up as you have the lever pulled in - to avoid sucking any air back into the master cylinder.
Once the lever is firm, make sure the reservoir is topped up to the right level, put the reservoir cap back on and give everything a final clean down (if you’ve spilled any fluid use some water to wash it away promptly)
When you first ride the bike after switching or overhauling any braking components test the brakes gently and in plenty of time to ensure its all working as expected.
If running race rearsets without a mount for the road brake light, install a banjo switch