Unofficial Royal Enfield Community Forum

Royal Enfield Motorcycles => Bullet with the UCE engine => Topic started by: Sectorsteve on November 25, 2013, 03:02:12 pm

Title: Brake pad question and hello again!
Post by: Sectorsteve on November 25, 2013, 03:02:12 pm
Hi all. It's been a while between posts. Hope you're all well and loving your rides.
I changed my front disc pads a little while back but have not noticed they are considerably rubbing on the disc . If you try to spin wheel freely it won't. I've just driven 600 km today from Sydney to beechworth and my fuel consumption is up a lot. Only got just under 300 km per tank which is good but I was getting 400. Could this be because of the front brake? I'd like to fix this before I leave back home in a few days ! Can anyone tell me how to fix this please! Greatly appreciated
Title: Re: Brake pad question and hello again!
Post by: GA-DK on November 25, 2013, 04:31:57 pm
I have not seen this on a bike, but I have had the brake pistons stick on my '89 Dodge diesel.  What a drag!  I would first check for fluid level.  With new, thicker pads, you could have too much fluid and pressing pistons in might spill fluid from MC.  Then check for free travel on pistons.  They should slide back with light finger pressure.  If they do not, that is you problem and dealer should be consulted.  I do not know how you would disassemble and clean.  GA-DK
Title: Re: Brake pad question and hello again!
Post by: barenekd on November 25, 2013, 05:50:57 pm
+1 on  the overfilled master cylinder. You probably topped off master cylinder before you changed pads. Now there's too much in there, not allowing the pads to retract enough.
To disassemble the pistons is quite easy. Take the wheel off, then squeeze the brake lever. That'll pop one of them out, making a big mess in the meantime! The other can be gotten out by refilling the master cylinder and blocking off the first side and squeezing again!
Now, in all seriosity, the piston can be pulled out fairly easily with a pair of water pump pliers, er, ChannelLocks. Still makes a mess when the fluid comes out. It should be necessary though. You might want to clean the gap in the bore with the pistons in with some brake cleaner. If the gaps get a lot of crud in them, that can keep the pistons from retracting.
Bare
Title: Re: Brake pad question and hello again!
Post by: Sectorsteve on November 25, 2013, 09:51:25 pm
Thanks for the replies guys. Sounds like something's sticking. Dunno. Thing is, I didn't do anything with brake fluid. All I did was swap the pads out.
Title: Re: Brake pad question and hello again!
Post by: Ducati Scotty on November 25, 2013, 10:04:35 pm
If the pistons are sticking a little blow out with and air compressor and some cleaning with brake cleaner and a tooth rush may work wonders.  Just pull the caliper off, remove the pads, and clean away.  Use the air compressor before the brake cleaner, not after.  You don't want to blow that stuff into your eyes.

Scott
Title: Re: Brake pad question and hello again!
Post by: Sectorsteve on November 25, 2013, 10:56:51 pm
Thanks legend. Sounds like the go to me!
Title: Re: Brake pad question and hello again!
Post by: Arizoni on November 25, 2013, 11:40:53 pm
Did you lightly grease the rods the brake pads ride on?  If not they may be hanging up on them.

It really sounds like this might be too much brake fluid in the system (even though you didn't add any).
This is easily fixed by removing the rubber cap from the bleed valve on the caliper.
Loosen the hex bleed valve about 1 turn and rotate the wheel. 
If excess fluid is the problem, some will squirt out when the valve is opened.
The open valve will also let the pads push the pistons back a bit when the wheel is rotated.  After doing this, tighten the valve using moderate (not hard) pressure.

If this doesn't fix the problem the pistons may be stuck in place.  If they are, then (and only then) you will have to disassemble the caliper like the others are suggesting.
Title: Re: Brake pad question and hello again!
Post by: Sectorsteve on November 26, 2013, 07:48:35 am
Hey thanks you guys. Thanks to you all my brakes are now sweet. I pulled caliper off and saw that one wasn't really wanting to move. I'm in a one horse town and the only option was a bit of wd40 to lube pistons. Did that wiped it all up but I will grease lightly the rods. I drained some of the fluid out. Did the trick. Free balling now and ready for the 650km commute home tomorrow. Thanks again x
Title: Re: Brake pad question and hello again!
Post by: Mr.Mazza on November 26, 2013, 10:45:52 am
Hey thanks you guys. Thanks to you all my brakes are now sweet. I pulled caliper off and saw that one wasn't really wanting to move. I'm in a one horse town and the only option was a bit of wd40 to lube pistons. Did that wiped it all up but I will grease lightly the rods. I drained some of the fluid out. Did the trick. Free balling now and ready for the 650km commute home tomorrow. Thanks again x

WD-40 is a good temp fix, I'd recommend investing in some anti-seize grease, it's what all mechanics use on slide bars for brakes, lubes and stops it seizing (Hopefully)
They aren't too much for a tin, and it'll last you forever.
Title: Re: Brake pad question and hello again!
Post by: ROVERMAN on November 26, 2013, 01:47:35 pm
Make sure anti sieze is not used around rubber or plastic.The correct lube is silicone grease, i use the brand called sil-glyde it won't deteriorate rubber and is waterproof.
Just my 10 cents worth.
Title: Re: Brake pad question and hello again!
Post by: Ducati Scotty on November 26, 2013, 04:14:05 pm
You can usually get a small packet of silicone grease at the auto store checkout for 99 cents.

Scott
Title: Re: Brake pad question and hello again!
Post by: ROVERMAN on November 26, 2013, 04:55:26 pm
+1 Scotty.
Title: Re: Brake pad question and hello again!
Post by: barenekd on November 26, 2013, 05:50:07 pm
take the cap off the master cylinder and push the pistons back in by hand. See if you're getting any overflow. The new pads may be thicker than the original ones.
Bare
Title: Re: Brake pad question and hello again!
Post by: Blairio on November 27, 2013, 05:00:01 am
If you don't have access to a compressor, the local electronic component store should have tins of 'Sprayduster'. This is basically an aerosol tin of compressed air, used for quickly cooling soldered joints, or blowing dust off circuit boards, heatsinks, fans and the like. Aside from electronics I have used it to clean out oilways in engine casings and airways in carburettors.
Title: Re: Brake pad question and hello again!
Post by: Craig McClure on November 28, 2013, 12:56:40 am
if you clamp a NOZZLE with a small restrictive opening in the valve chuck of a hand/manual tire pump it works very well to blow out dirt from crevices. My Ural came with this attachment for its on board manual tire pump.   Perhaps you could adapt a piece off a cheap HARBOR FREIGHT blow gun.
Title: Re: Brake pad question and hello again!
Post by: High On Octane on November 28, 2013, 03:25:09 am
HF blow guns, how do I say this?  Blow.  I have purchased 3 different ones and they all failed within 2 days use.  I don't know what you guys have for tool stores or brand availability there Down Under but Campbell Hausfeld makes a good one for cheap.

Scottie