Shimano M665 bleeding?

bobbydigital

Just wondering if anyone has experience bleeding these brakes?



I have bled many systems without any big issues, I can get avids up to pressure, spot on, no issues but these seem like a huge pain in the butt.

I've tried the Shimano method, which is pump lever a few times, hold lever, open bleed nipple, close nipple, pump brake and repeat.

I've tried reverse bleeding, so pushing fluid from the caliper up into the reservoir and removing any bubbles from the reservoir.

I get no air coming out of the system now.

Using the proper Shimano brake oil.

I've tried tapping the caliper, hose, master cylinder with the end of a screw driver to release any bubbles, left a velcro strap around the brake over night but it's just not as good as I'd expect a SLX brake to be, the lever just doesn't feel as solid as expected. It bites not too far from the extended position but it's spongy still.

I have an old hope for the front brake, the little mini caliper and the lever on the master cylinder for that is spot on.

Dump your avids they said, Shimanos are easy to bleed! :twisted:

LimitedGarry

This brake is at least 9 years old tech. Should have gone with M666 or later.
Where did you get the 665 anyways? Even the M666 is out of stock pretty much anywhere.

whyamihere

The way I used to bleed the old Shimanos was the same as you would do for a car. Attach a hose to the bleed nipple, open it, pull the lever, close it, release the lever, repeat, and make sure the reservoir is kept topped up.

It's a hell of a lot easier with the new brakes which you bleed using the funnel.

bobbydigital

LimitedGarry wrote:

This brake is at least 9 years old tech. Should have gone with M666 or later.
Where did you get the 665 anyways? Even the M666 is out of stock pretty much anywhere.

I got it from a bike shop ebay seller, new old stock, it's not for my personal bike but a bike I will sale, so keeping costs down, I just needed any decent hydraulic brake and thought, shimano, slx, radical master cylinder, should be good!

whyamihere wrote:

The way I used to bleed the old Shimanos was the same as you would do for a car. Attach a hose to the bleed nipple, open it, pull the lever, close it, release the lever, repeat, and make sure the reservoir is kept topped up.

It's a hell of a lot easier with the new brakes which you bleed using the funnel.

Yeah that's I did for a long time, air stopped coming out after about 5 minutes, but overall I kept going back to see if I could make them feel better, lever bites early enough just it flexes a bit, wasn't sure if it was just a bad design hence why like you said they use the funnel brakes now.

02gf74

whyamihere wrote:

The way I used to bleed the old Shimanos was the same as you would do for a car. Attach a hose to the bleed nipple, open it, pull the lever, close it, release the lever, repeat, and make sure the reservoir is kept topped up.

It's a hell of a lot easier with the new brakes which you bleed using the funnel.

Yeah that's I did for a long time, air stopped coming out after about 5 minutes, but overall I kept going back to see if I could make them feel better, lever bites early enough just it flexes a bit, wasn't sure if it was just a bad design hence why like you said they use the funnel brakes now.

these type with reservoir are easy to bleed, just be sure the level is kept topped up else your bleeding is undone when air gets into the system. without knowing how hard you are pulling on the lever and how much flex there is, it is hard to make a reasoned comment but if you have not air bubbles, then the system is as good as it can be. The lever may feel a bit spongey due to design , I generally find shimano (xt/xtr) brakes pretty solid - could be how it is for lower end brakes.

The Rookie

Never had any issues with that style lever, mount it flat, remove the resevoir cap, drain the resevoir using a syringe and tube then fill syringe and fill via the calliper, make sure the pistons are pushed fully back first.