Front brakes dragging after bleed

[fireypete]

Hello All,
This has got me stumped.  All I have done is put fresh fluid in the reservoir whilst bleeding out at the caliper, you know squeeze lever open bleed valve, close valve release lever so on and so forth.
The brakes were really dragging when I finished, I repeated the bleed process very gently on both sides, small squeeze of lever, just a little fluid out and it seemed to help..a bit. I cannot fathom how i may have built pressure up in the calipers...
I did the Interceptor 650, same issue but i think I over filled the reservoir, not so on the Tiger.
Help me MR Wizard....Oh and Ms Wizard and gender non specific wizards out there

[Paul2bikes]

Is the fluid at mid-level between the marks?

Have you serviced the calipers? If not, could be dirty pistons, or corrosion behind the dust seal in the groove forcing seal tight on piston so it is not releasing.

[fireypete]

Hello Paul
The fluid level is now a little under the high mark.  I'm going to pull the front wheel so I can better look at the pistons, I would think they are dirty.  They did not drag much before I touched 'em.  If I lift the front wheel and give it a  decent spin with the other hand i get a  full rotation,and thats it.
The rear, I did the same, and its good.

[Zevk]

Hi fireypete,

perhaps during the process, a calliper piston got slightly “hung up” ie crud collected between piston and seal

Try to remove the calliper, spray brake cleaner and use your partners / brother / sisters toothbrush, to scrub out the brake dust, while pressing the piston in and carefully squeezing the front and rear brake, scrub away, then clean with brake spray cleaner

While the calliper is off the rotor, remove and clean the brake pads, inspect thickness and clean the shudder brackets, brake pins and pad detents

Apply bendix blue grease (sold in sachets at Supercheap auto) to the pad tangs and backing plates

Sorry if you know or have already done all this…

Hope this resolves your problem 

[Zevk]

Hi fireypete,

perhaps during the process, a calliper piston got slightly “hung up” ie crud collected between piston and seal

Try to remove the calliper, spray brake cleaner and use your partners / brother / sisters toothbrush, to scrub out the brake dust, while pressing the piston in and carefully squeezing the front and rear brake, scrub away, then clean with brake spray cleaner

While the calliper is off the rotor, remove and clean the brake pads, inspect thickness and clean the shudder brackets, brake pins and pad detents

Apply bendix blue grease (sold in sachets at Supercheap auto) to the pad tangs and backing plates

Sorry if you know or have already done all this…

Hope this resolves your problem 

[Paul2bikes]

Originally Posted by fireypete

Hello Paul
The fluid level is now a little under the high mark.  I'm going to pull the front wheel so I can better look at the pistons, I would think they are dirty.  They did not drag much before I touched 'em.  If I lift the front wheel and give it a  decent spin with the other hand i get a  full rotation,and thats it.
The rear, I did the same, and its good.

I like the fluid level more towards the mid-mark. You don't need to remove the wheel, just remove the calipers, clean up as ZevK said, then check for free movement of the pistons, if you can't push each in by hand, they need a full service with new seals, most likely that dust seal groove will be corroded, needing a clean out then a lick of rubber grease in there & the seal.
Good luck with it.

[Rhead]

If you can spin the wheel by hand, it should be fine. Mine are always a little sticky after messing with them. A ride using the brakes a lot fixes that every time.

[chwinc]

Originally Posted by Rhead

If you can spin the wheel by hand, it should be fine. Mine are always a little sticky after messing with them. A ride using the brakes a lot fixes that every time.
[/quotez]
Totally agree with Rhead take it for a spin apply brakes as normal ,it will allow the seals to retract the pistons properly

[fireypete]

Thanks guys.  I'm "working from home today"   So, the interceptor can sit in the shed and I will give the Tiger a good run..I will pull those calipers off this weekend for a look.

[fireypete]

Ok, took the Tiger out and the brakes felt HOT after 5k, nursed her home and whilst they were not as hot as the first 5K I  pulled the calipers and gave a basic clean, bit of lube. Couple of Pistons had tiny bit of corrosion on the very edge. Still a bit of drag, but unless they get hot during a ride (not using them) I wont worry.  Perhaps the seals have had it and are grabbing?  No signs of a leak anywhere.  I must confess, the brake fluid I changed out was rather horrible...