I have recently bought a 2013 California 1400 Custom…from The Scooter Cafe in Maidenhead , I was thoroughly enjoying the lovely grunty engine ,although fuel economy is not great…but is a big motor and a very heavy bike.
After 500 miles or so I was out close to home when I became aware of vibration, not severe, but unusual as it is normally very smooth. Suddenly there was a loud bang, and i saw a big cloud of smoke in the mirrors…
I pulled in to find flames under the rear panniers, quickly put out using a puddle…on examination i found the vibration had been caused by the rear caliper biding on the disc, then grabbing and exploding, the inner half of the caliper had broken off, and it and both pads had disappeared…
In 40 years of biking , and having owned 30 bikes I have never had anything like it.
The dealer is being very helpful we have sourced a used caliper, which will be overhauled and fitted with a new disc and pads, and he will extend the three months warranty for the time it off the road.
The bike has factory panniers and it is a faff removing them to check the caliper…but is something I shall be doing regularly from now on…
Hi Brevabob, check out the 1400 California section in the Technical section of the club Forum. I recall a Scottish member consuming rear brake pads within 300 miles. There may be some clues to your problem there. Cheers Phil
It’s not an uncommon problem on the 1400s.
Never had a calliper explode but I’ve experienced sticking rear brake on both the 1400s I’ve owned.
There are two causes that I’m aware of. First and less common is a stone or other foreign object getting stuck between the brake pedal and the frame causing the brake to stick on. I’ve had this happen once.
Second & much more common is the pads & or the piston sticking in the calliper.
My remedy is regular maintenance, every six months if possible, especially after winter & salty roads.
thanks for your reply…i am sure it was the piston …and we have a used caliper and overhaul kit as well as a new disc going on…hopefully this will resolve it, and i will be checking religiously from now on…
If the caliper has only got 1 piston, it is a sliding caliper type.
They work on the principle that as the piston extends and presses the brake pad onto one side of the disc, the caliper body slides on guide pins and “pulls” the other pad onto the other side of the disc. Equal and opposite, and all that…
They work quite well…until they don’t.
99 times out of 100, the problem is caused by the caliper seizing on the guide pins so that it cannot move freely and do the “pull” bit, leading to uneven pad wear…or worse.
Only way around it is to religiously keep the caliper pins clean and greased so that the assembly is free to move.
Hi Speedy 23, I’m not aware of any disc brakes Moto Guzzi that used the sliding caliper type of braking system. They have all used, at the very least, dual piston brake callipers. Cheers Phil
Brake pads rub the disc, the friction causes the disc and pads to expand which creates more heat, more expansion until as you found out, a catastrophic failure happens. Luckily for you the disc didn’t shatter and cause a massive seizure together with loss of control of the bike.
Normally in such circumstances you would feel the bike slowing down but being as it is such a heavy bike and new to you you probably didn’t realise it; almost certainly why the fuel consumption was so poor as well.
What causes it?
Inadvertent pressure on the rear brake pedal especially with those of us with big feet.
Insufficient brake pedal clearance that does not allow the pads to cool down after use.
Poor service/maintenance with regard to brake fluid replacement; wrong fluid used with an incorrect boiling point; possibly system not bled properly when fluid was replaced. With regard to the last point I’ve had two bikes which were complete barstewards when bleeding the back brake, both Kawasaki’s for some reason.
Good to see that the dealer is replacing everything under warranty plus extending your warranty. Clearly the dealer did not check the bike’s service history or give it a good going over replacing all fluids and filters if there was no service history prior to selling it to you.
The real cause of the California brake debacle is the master cylinder had corroded inside and was not returning when applied
New master cylinder should be with the dealer this week along with a new ABS sensor…
Hopefully I will be able to get out on it next week…
The drama continues…Guzzi said they would send a new master cylinder…then a week later told the dealer that they had no stock …
I have sourced a used one from Teo Lamers…hopefully we should have that soon…
The bike has been off the road for well over a month…and it is annoying that a manufacturer cannot help with parts for a bike that was in production 3 years ago…
Ironically, since I posted a few weeks back, my 1400 Eldorado developed a similar sticking rear brake problem that I’d previously experienced on my 1400 California.
Like Bob’s bike, on inspection the problem turned out to be caused by the master cylinder not the caliper.
I didn’t suffer total meltdown, but the caliper had got very hot, so I rebuilt it using new seals & stainless pistons. Rather than replace the master cylinder I substituted it with a new Brembo.
The root cause of the issue appears to be the rubber boot that seals the actuating rod where it enters the master cylinder. This boot doesn’t do a great job, allowing moisture & dirt to get to the piston, ultimately causing corrosion & the piston to stick in the bore.
On inspection my 2019 10,000 mile Eldo was already badly corroded.
For those interested in the Brembo modification there’s a great video on YouTube, it’s on the Moto Schrauber channel. It’s in German, but as they say, “a picture paints a thousand words”
Finally I have got my bike back…it seems fine…full service, front and rear brake pads replaced, used rear caliper and used rear master cylinder, new rear disc and new ABS sensor fitted
The Scooter Cafe both collected and delivered the bike…and have repaired the rear brake parts under warranty. They have been excellent to deal with
The biggest frustration has been the inability of Moto Guzzi to supply a new caliper or master cylinder, although my bike is a 2013 machine the California was in production 2 years ago.
Onwards and upwards…I will be going to Ireland in June for the Killarney Bike Festival, hopefully no more issues.
