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Discussion Starter · #1 ·
Hi,

I just bought a pair of XTR M9100 levers, and have them fitted to a pair of SLX M7100 callipers.

The SLX M7100 levers which were fitted before had a good biting point, and felt solid. The XTR levers bite very late, despite me bleeding air out of the system, from both ends, following the exact Shimano dealer manual instructions.

The only thing I have managed to do to improve the bite point, is to inject more brake fluid up into the system from the caliper, but I am loath to keep this extra volume of oil in there as I fear the lever reservoir end cap will burst on hard braking (and my method here is not mentioned in any of the documentation).

Anyone got any insight into this, as I am running out of ideas...

Cheers
 

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Ridden XT on all bikes for the past 10 years

I’ve found my 9100 not to my liking
The front end hardly does anything
The rear dose nothing then locks up.
And the rear was slow to return, it would rub for ages.
So I got the bike shop to re oil and bleed, replacing the resin pads with metal.
Sadly Still no good
Then I replaced them with 9120. Perfect
Not finished with the 9100 I got another bike shop to fit them to my old bike, but they couldn’t get them to work properly either
 

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Discussion Starter · #3 ·
Update;

I have managed to get the front brake biting well, but it took a LOT of bleeding, using the following;

1. Tapping everywhere on the entire brake assembly for AGES, with a bleed cup on the lever, and getting as many bubbles out as I could there. Was a seemingly endless exercise.
2. Dragging bubble filled fluid back out of the calliper end of the system, using a syringe, and reinjecting bubble free fluid in.

After spending about half an hour on this, the brake finally started feeling tight and sharp.

The rear one will get the same treatment next.

So in short, there were a lot of bubbles in the system. Hardly a revelation, I know, but thought I would share.
 

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The Shimano brakes should not overfilled to prevent bursting the rubber membrane, but a good bleed is essential.

Also make sure the pistons are not sticking. I had to work mine over several times last month to get the front from rubbing after prolonged braking. I used mineral oil on the pistons, working them in and out several times and then a good clean.
 

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Do you mean the lever reach grub screw, or the free stroke adjustment screw. If you mean the latter, then this does not exist on the BL-M9100 levers.
Do you mean the lever reach grub screw, or the free stroke adjustment screw. If you mean the latter, then this does not exist on the BL-M9100 levers.
ugh, you are right. i confused this with the 9120 ones. and yes i mean the free stroke adjustment screw. hmmm, wondering how it works for those levers then. because if i bleed mine and i don't undo that screw i get exactly the symptoms you describe: bubbles until the end of time. hmm hmm.

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ugh, you are right. i confused this with the 9120 ones. and yes i mean the free stroke adjustment screw. hmmm, wondering how it works for those levers then. because if i bleed mine and i don't undo that screw i get exactly the symptoms you describe: bubbles until the end of time. hmm hmm.

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or more concise. it seems that opening that screw makes bleeding much easier.

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