Author Topic: Front brake dragging.. from the spring loaded arm? (Read 2314 times)

singedebile · « **on:** February 17, 2011, 01:28:22 PM »

'75 cb550f

I figured out why my inside pad was dragging i think and its because the arm is sticking so it does not return after releasing the brakes.. I am assuming its supposed to recenter itself..

I havnt seen mention of this and wasnt sure how to search for it..

Do you have to disassemble the pivot point? or is there a way to adjust it? do I "have" to take off my front wheel (my bike is in my room now.. i can do it but there is not much room).

Roach · « **Reply #1 on:** February 17, 2011, 01:33:15 PM »

if im correct the pivot should swing free it doesnt have a spring in it or anything aslong as it lubed it should move.

hows the spring look? has it lost its bounce?

singedebile · « **Reply #2 on:** February 17, 2011, 01:44:40 PM »

the spring still has a bit of spring to it, but its not a super hefty spring and cant quite overcome the arms stiffness

underachiever · « **Reply #3 on:** February 17, 2011, 01:47:00 PM »

You don't have to remove the wheel though it helps to get it off the ground so you can spin it to see if it's dragging. If adjusting the centring screw/bolt doesn't remove the dragging it should be serviced. Remember that the clearance to the inside pad is really tight, .006".

You can just unbolt the halves of the caliper to get them out of the way, then undo the bolts holding the arm in place and remove the centring bolt, nut and spring. Then you can take it all off, take it apart and give it a thorough cleaning and re-greasing. It should swing easily.

While it's off, it's a good time to polish'er up.

singedebile · « **Reply #4 on:** February 17, 2011, 01:59:57 PM »

alright, so i guess take the arm apart is pretty straightforward.. i just took the front wheel off ..time to keep unbolting stuff

flybox1 · « **Reply #5 on:** February 17, 2011, 02:02:28 PM »

Quote from: Roach on February 17, 2011, 01:33:15 PM

if im correct the pivot should swing free it doesnt have a spring in it or anything aslong as it lubed it should move.

with or without the spring, it should swing freely.
lift and spin your front, if it drags, as others have said, remove, clean and lube the pivot pin, and you should be good to go.
a ride around the block, using only your rear brake will let you feel the front rotor for heat. after you stop.
if its warn, its still draggin'

TwoTired · « **Reply #6 on:** February 17, 2011, 02:04:37 PM »

The square section seal in the caliper distorts to a parallelogram when the piston is pushed towards the disk. Upon release the seal returns to square and retracts the piston away from the disk.

The spring you speak of, compresses slightly when the brakes are applied to allow the stationary side contact with the disk.

With no pressure or contact with the puck on the piston side, the stationary pad is adjusted for 0.006 In. clearance to the rotor via the adjuster under the spring.

If the piston is not too pitted where it contacts the square section seal (distorting the seal's square contour), or the caliper isn't binding from corrosion and hardened brake fluid, the caliper side puck should free 99% of the contact with the disk and the spring should do the same to the stationary pad.

Cheers,

singedebile · « **Reply #7 on:** February 17, 2011, 02:11:01 PM »

ok then maybe it wasnt just this that was making the pad stick, if and should i still remove the pivot pin? ive spun it around a bunch of times now that its off and it a bit better. How do I take the pivot out? is it threaded in?

and while im at it, apart from going for the stock look does that 'rain shield' do much? should I put it back? My bike is never going to be a show bike but if it doesnt do anything (maybe modern brake pads alleviate the problem that it solved?)then I will leave it off.. but I am happy to put it back on.

ps: this is the most involved thing I have done with the bike so far.. im having quite a bit of fun i have to say, I also just took the MC apart (after much much fun.. i slightly different kind, with the cir-clip)

britz73 · « **Reply #8 on:** February 17, 2011, 02:16:39 PM »

The pivot point has a mounting cap and pin. There should be 2 o'rings - 1 either side. Remove from caliper mount and take it apart, very easy. Don't loose the o'rings. Lube up to your hearts content and it will free up.

TwoTired · « **Reply #9 on:** February 17, 2011, 02:19:40 PM »

The splash guard is to keep rain, road gunge, and puddles from flinging onto the rider in a steady stream.

The bike won't care if you leave it off, the rider will.

singedebile · « **Reply #10 on:** February 17, 2011, 02:30:32 PM »

Quote from: TwoTired on February 17, 2011, 02:19:40 PM

The splash guard is to keep rain, road gunge, and puddles from flinging onto the rider in a steady stream.

The bike won't care if you leave it off, the rider will.

haha no i dont mean the fenders, i like them.. was even thinking of getting a mudflap! I was talking about the little plastic thing over the disk brake

TwoTired · « **Reply #11 on:** February 17, 2011, 02:35:13 PM »

Quote from: singedebile on February 17, 2011, 02:30:32 PM

Quote from: TwoTired on February 17, 2011, 02:19:40 PM
The splash guard is to keep rain, road gunge, and puddles from flinging onto the rider in a steady stream.

The bike won't care if you leave it off, the rider will.

haha no i dont mean the fenders, i like them.. was even thinking of getting a mudflap! I was talking about the little plastic thing over the disk brake

So was I.
It spins, it gets wet, water fly's off into the path of the rider.

singedebile · « **Reply #12 on:** February 17, 2011, 02:37:57 PM »

Quote from: TwoTired on February 17, 2011, 02:35:13 PM

Quote from: singedebile on February 17, 2011, 02:30:32 PM
Quote from: TwoTired on February 17, 2011, 02:19:40 PM
The splash guard is to keep rain, road gunge, and puddles from flinging onto the rider in a steady stream.

The bike won't care if you leave it off, the rider will.

haha no i dont mean the fenders, i like them.. was even thinking of getting a mudflap! I was talking about the little plastic thing over the disk brake

So was I.
It spins, it gets wet, water fly's off into the path of the rider.

even better! interesting.. I will leave it on then. I wonder why modern bikes dont have them

and back to the task at hand... the arm is moving well now and I am going to start reassembling everything from the the caliper to the MC. The pad is stuck and im working on that now (ive read a bunch of advice on it already so it should only be a matter of time)

thanks for the help!

seanbarney41 · « **Reply #13 on:** February 17, 2011, 03:00:03 PM »

What's good to use for lube on that pivot pin? Mine has been working well for years. Took it apart for cleaning/polishing/maintenance and whatever lube was in there looked more like motor oil than grease.

britz73 · « **Reply #14 on:** February 17, 2011, 03:06:22 PM »

I would suggest "Never seize", but not sure if you have this in the US? Whatever you choose you may need to consider compatibility with the alloy..........my 10c anyway.

seanbarney41 · « **Reply #15 on:** February 17, 2011, 03:12:09 PM »

Is that just a basic anti-sieze compound such as you would use on a spark plug or an exhaust header stud/bolt?

britz73 · « **Reply #16 on:** February 17, 2011, 04:12:34 PM »

Yep. It's a real pain in the arse to get off your hands..............

singedebile · « **Reply #17 on:** February 17, 2011, 04:14:58 PM »

a quick question, i just put the MC back together and was going to try pushing the front pad out by pumping the brakes.. but i have an "extra" oval like washer with a hole and a bump on it that goes with the brake lever.. its not mentioned on the diagram for the shop manual and I cant figure out which way it should face and if it should be on the top or bottom.

sniper1 · « **Reply #18 on:** February 17, 2011, 04:33:19 PM »

I had the same exact problem. It had nothing to do with the spring. Replace the piston seal. Its about a 30 minute project, no more dragging or squeaking. I did a write up on it on here. I messed with the brake system for about three weeks before I got the new seal and dropped it in, reassembled it and now it works great,,,,,,,well good for a '77 disk brake, anyway.

seanbarney41 · « **Reply #19 on:** February 17, 2011, 04:44:45 PM »

Quote from: singedebile on February 17, 2011, 04:14:58 PM

a quick question, i just put the MC back together and was going to try pushing the front pad out by pumping the brakes.. but i have an "extra" oval like washer with a hole and a bump on it that goes with the brake lever.. its not mentioned on the diagram for the shop manual and I cant figure out which way it should face and if it should be on the top or bottom.

yeah, that thing goes on the bottom the brake handle pivot bolt, that little bump goe sin an indentation on the bottom of the mc. Why and what for?...I don't know

Hinomaru · « **Reply #20 on:** February 17, 2011, 05:10:18 PM »

Quote from: singedebile on February 17, 2011, 04:14:58 PM

a quick question, i just put the MC back together and was going to try pushing the front pad out by pumping the brakes.. but i have an "extra" oval like washer with a hole and a bump on it that goes with the brake lever.. its not mentioned on the diagram for the shop manual and I cant figure out which way it should face and if it should be on the top or bottom.

Refer to the 1975 CB550F parts diagram:

http://www.mrcycles.com/fiche_section_detail.asp?section=123093&category=MOTORCYCLES&make=HONDA&year=1975&fveh=2942

That oval plate (#14) keeps the rubber bush (#13) from falling out. The rubber bush keeps your brake lever from rattling around by removing the free play. If your rubber bush is missing or has seen it's better days, go ahead and replace it. You'll be glad you did.

seanbarney41 · « **Reply #21 on:** February 17, 2011, 05:31:39 PM »

Woah, woah, woah...I had no idea there was ever a rubber bushing involved! That makes a lot of sense! Don't tell me there is supposed to be one in my sloppy clutch lever too!

chippyfive50 · « **Reply #22 on:** February 17, 2011, 07:52:55 PM »

Mine was dragging ever so slightly.
It was because when I reinstalled the wheel and tightened the caps, the fork on the side without the flange on the end of the axle(non disk) was not seated in flush on the inside.
This caused the wheel to be cocked just a CHair, just enough for my brake to heat up over a mile , and start squeaking, dragging.
Losened the caps, whacked the fork on the Side, fixed.

Duke McDukiedook · « **Reply #23 on:** February 17, 2011, 10:52:28 PM »

Quote from: singedebile on February 17, 2011, 02:37:57 PM

Quote from: TwoTired on February 17, 2011, 02:35:13 PM
Quote from: singedebile on February 17, 2011, 02:30:32 PM
Quote from: TwoTired on February 17, 2011, 02:19:40 PM
The splash guard is to keep rain, road gunge, and puddles from flinging onto the rider in a steady stream.

The bike won't care if you leave it off, the rider will.

haha no i dont mean the fenders, i like them.. was even thinking of getting a mudflap! I was talking about the little plastic thing over the disk brake

So was I.
It spins, it gets wet, water fly's off into the path of the rider.

even better! interesting.. I will leave it on then. I wonder why modern bikes dont have them

and back to the task at hand... the arm is moving well now and I am going to start reassembling everything from the the caliper to the MC. The pad is stuck and im working on that now (ive read a bunch of advice on it already so it should only be a matter of time)

thanks for the help!

The amazing Carmac forsees a caliper rebuild in your future... Look to Lloyd's rebuild info in the brake FAQ...

News:

Author Topic: Front brake dragging.. from the spring loaded arm? (Read 2314 times)

Hinomaru