Brake calliper problem.

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Brake calliper problem.

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beaglebasher
yesterday

I went to change the rear brake pads yesterday. Pulled the old ones out but couldn't get the inner one back in but you could throw the outer one in from across the room. After the odd swear word I realised that the calliper is not even close to being centred on the disc.
It's a 2002 fatboy with a 150 tyre and the calliper is anchored on the axle.
I always knew that the back brake was dragging a little bit cos whenever I got off the bike the disc was always too hot to touch, even when I deliberately didn't use the back brake but I just assumed it would have been a sticky piston so didn't worry about it.
I haven't pulled it apart yet but from what I can see I am thinking the only way the calliper can be offset to the disc is if the wrong spacers have been fitted at some point.
Surely it couldn't have come out of the factory like that. The bike is pretty well bog standard as far as I know.
I will go and take a couple of pics.

beaglebasher
yesterday

Hilly
yesterday

Well it's been through a few tyre changes beages so the possibility is there that someone mixed up spacers at some point, it's not frozen on the pins is it? That's something that does happen quite often.

beaglebasher
yesterday

I used a set of drills as feeler gauges and there's roughly a 3.5 mm difference either side. The inner pad that came out was nearly down to the metal and the outer pad was maybe 10% worn.
Looks like I will have to be machining new spacers.

beaglebasher
yesterday

Quoting Hilly on 16 Nov 2025 09:44 AM
Well it's been through a few tyre changes beages so the possibility is there that someone mixed up spacers at some point, it's not frozen on the pins is it? That's something that does happen quite often.

I am thinking that's the only way it could happen.
The mechanic that changed the tyre the last time must have been a rough prick cos it would need a fair bit of brute force and ignorance to get the bastard in.

Hilly
yesterday

If your sure the caliper is ok maybe the spacers are on the wrong sides? They are different but off the top off my head I can't recall how.

Hilly
yesterday

43654-00A disc side
41595-00B pulley side
According to the parts fiche
Dunno dimensions though

beaglebasher
yesterday

Yeah mate, there's a big difference either side. The one on the left looks like it's well over an inch long and the one on the right is around 1/2 inch. When I pull it apart tomorrow I will know more but I'm thinking I might have to adjust the spacers to move it over about 2mm.

408
18 hours ago

Your left length is shown as 1.875" or 1.897" and the right as 0.475".
If they are much different to that, it is possible someone may have put a different model rear wheel in there.
Check for correct mounting of disc and pulley.

speedzter
17 hours ago

When did you last replace wheel bearings .
Some wheels need to have one side bearing seated first, then the other to just touch the internal spacer.

beaglebasher
15 hours ago

Quoting 408 on 16 Nov 2025 09:05 PM
Your left length is shown as 1.875" or 1.897" and the right as 0.475".
If they are much different to that, it is possible someone may have put a different model rear wheel in there.
Check for correct mounting of disc and pulley.

Thanks for the information 408.
I will hopefully get the time to pull it apart this arvo and try to figure out what's going on.

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beaglebasher
15 hours ago

Quoting speedzter on 16 Nov 2025 09:49 PM
When did you last replace wheel bearings .
Some wheels need to have one side bearing seated first, then the other to just touch the internal spacer.

I got the local mechanic to replace the brake pads when I first bought the bike about 12 or 13 years ago.
I told him to go over the whole bike and do anything that needed done.
He replaced the front and back wheel bearings at the sametime. The same bloke has replaced the back tyre 3 times since then.
I am pretty sure that the inside pad has been rubbing the disc for at least 13 years.

beaglebasher
15 hours ago

The one on the left is the inside pad.

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Retroman
15 hours ago

I had a 2008 Softail Custom bought new, just over 2 years old needed a rear tyre. Out of warranty

Back to the HD dealer (Frasers Perth) 'cause they would fix it right eh ?

Front tyres I do myself, loose wheel in etc etc.

Rears are a Kayhunt to do at home, so in it goes.

190K's later I am out of town and the bike starts shooting bearing balls out the back at 110Km/H. (fucking scary at 40/50 Km/H)

Wheel is moving 2cm left to right, and I ride it home then into the shop the next day, Totally rooted.

The wheel had been put in with both side spacers 180 degrees out, and one was chamfered, now pressing on the inner race.

They claimed " not warranty". I point out the "mistake" on reassembly. I lead the service reception guy to the new bikes in the showroom. Point out the fucking obvious (politely).

The foreman mechanic then says to me at the time, heated conversation, "What the fuck do you know ?"

I reply "don't assume all of your customers are idiots mate" and go straight to the dealer principal and "explain" the scene.

Compromise (face saving) deal for them is, I pay for the new bearing set ($60) and they fit them as "good will".

LOADS of labour in that so I relent and wait around for 3 hours.

Fuck me, when it's done the spacers are in correctly LIKE I FUCKING SAID ! I do another 45,000K's on that bike no worries.

So, in short, yes they can get it wrong, quite easily done

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beaglebasher
11 hours ago

Quoting 408 on 16 Nov 2025 09:05 PM
Your left length is shown as 1.875" or 1.897" and the right as 0.475".
If they are much different to that, it is possible someone may have put a different model rear wheel in there.
Check for correct mounting of disc and pulley.

Just pulled it apart and measured the spacers. The left one is exactly 1.875" and the right one is 0.515" so 0.040" (1mm) longer than your sizes.
I double checked the offset and it's 3mm so if I take 1.5mm (0.060") off the right hand spacer it should bring the calliper in enough to line up with the disc. The spacer will end up being a bit shorter than your sizes but I don't think that will cause any problems.
I don't have a lathe but I'm pretty fuckin handy with an angle grinder!

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408
11 hours ago

Quoting 408 on 16 Nov 2025 09:05 PM
Your left length is shown as 1.875" or 1.897" and the right as 0.475".
If they are much different to that, it is possible someone may have put a different model rear wheel in there.
Check for correct mounting of disc and pulley.

Quoting beaglebasher on 17 Nov 2025 03:24 AM
Just pulled it apart and measured the spacers. The left one is exactly 1.875" and the right one is 0.515" so 0.040" (1mm) longer than your sizes.
I double checked the offset and it's 3mm so if I take 1.5mm (0.060") off the right hand spacer it should bring the calliper in enough to line up with the disc. The spacer will end up being a bit shorter than your sizes but I don't think that will cause any problems.
I don't have a lathe but I'm pretty fuckin handy with an angle grinder!

Doesn't matter how you get there but square is important.

Hilly
11 hours ago

It's gotta be square Beages or you will be spitting bearing balls out much like retros did, outa square puts a side load on them, they don't last long. I'm scratching my head a bit with this one, think I'd need to lay eyes on it to make sense of it, maybe it's an age thing.

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408
11 hours ago

Quoting Hilly on 17 Nov 2025 03:52 AM
It's gotta be square Beages or you will be spitting bearing balls out much like retros did, outa square puts a side load on them, they don't last long. I'm scratching my head a bit with this one, think I'd need to lay eyes on it to make sense of it, maybe it's an age thing.

The increased length of the spacer would be holding the wheel (and the disc) away from the caliper mount.
The disc would be loaded against the inside pad.

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beaglebasher
9 hours ago

I didn't use the angle grinder. I used the linisher and measured it every couple of grinds. It's within a thou of square so that should be OK. Took me a while but.
It's only 5 thou undersize from 408's numbers so it won't be dead centre on the disc but it should be a fuckload better.

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