[silentservice703]

There are numerous accounts of air in the rear brake system of several models of the 3-Cylinder bikes.
I was perusing a Ducati Forum and ran across the following issue with the crimping on certain ABS equipped Ducati bikes.
As this issue pertains to a very similar, if not the same, equipment on the MV bikes, I thought it might be of interest and might be the actual problem.

 

[dansoarr]

interesting indeed.

 

[PTsalas]

Thanks for posting though I don't think that might be it. My F3 doesnt have ABS and the problem is there.

 

[lussoscs]

There are numerous accounts of air in the rear brake system of several models of the 3-Cylinder bikes.
I was perusing a Ducati Forum and ran across the following issue with the crimping on certain ABS equipped Ducati bikes.
As this issue pertains to a very similar, if not the same, equipment on the MV bikes, I thought it might be of interest and might be the actual problem.

View attachment 478843

Interesting Indeed
Thanks

 

[Panchomeneguzi]

I think the problem is because the rear caliper is upside down. The valve points down, so the air stays inside the caliper in the opposite side to the valve. I removed and Turned it and then bleed the air. Problem solved for me

 

[silentservice703]

@Panchomeneguzi ... if you look across brands, you will see that most rear calipers are in that orientation.

 

[Mounatin Fun]

I think the problem is because the rear caliper is upside down. The valve points down, so the air stays inside the caliper in the opposite side to the valve. I removed and Turned it and then bleed the air. Problem solved for me

I'm curious...Do all MV models have the same rear brake hose ( sorry I'm not very technical).

Panchmeneguzi - how long ago did you do this as it appears the problem appears solved for many with bleeding etc for a few weeks to then find out their rear brake is useless again.

 

[Highside43]

Mine is fine since bleeding the shit out of it (no specialprocedure, just as normal and I didn't remove anything) when it was a month old, and I hang a 5 litre tub (of PVA glue if it makes any difference) each time it's parked up in man cave. I took it out the other day, first time in months and rear brake worked a treat, anti lock kicks in and slows bike more than I always remember when using it alone.

I know it's not acceptable on a premium product but I don't mind. Hanging the weight off and plugging in the charger is all part of the locking up process now.

Just my 2p's worth.

 

[lucydad]

There are numerous accounts of air in the rear brake system of several models of the 3-Cylinder bikes.
I was perusing a Ducati Forum and ran across the following issue with the crimping on certain ABS equipped Ducati bikes.
As this issue pertains to a very similar, if not the same, equipment on the MV bikes, I thought it might be of interest and might be the actual problem.

View attachment 478843

Could be a logical cause. Grazie!

 

[Panchomeneguzi]

I'm curious...Do all MV models have the same rear brake hose ( sorry I'm not very technical).

Panchmeneguzi - how long ago did you do this as it appears the problem appears solved for many with bleeding etc for a few weeks to then find out their rear brake is useless again.

My brake light stoped working because a malfunction in the pressure sensor. So I had to bleed and replace the sensor.
After that, the brake was useless. I repeated the process but when I thought it will work, it became useless again.
When I asked for help to the dealer, he told me that probably it was an air bubble in the upper side of the caliper, and since the valve is pointing down, that bubble was trapped and couldn't get out.

So, I removed the caliper, turned it so the valve where pointing up, repeated the process of bleeding and filling. Just that and it worked like magic. That was like 20.000 km ago, and never had a problem again. Abs always pup up when I want to test it and I don't have to put all my weight in the rear brake.

 

[Tony F]

MV have issued a new "MV Agusta internal service bulletin that MV dealers and service agents are following" with a new bleed procedure for the rear brake. It seems that the process has been carried out on some bikes with the process being filmed and sent to MV. The MV NZ rep advises that it is an internal document so cant be shared. But he is sorry. Surely someone will leak it!

The source of this was a discussion on the MV New Zealand facebook page where a few owners of 3 cylinder bikes were expressing frustration but the discussion has since disappeared from the page.

 

[silentservice703]

@Tony F: How "new"?

There has been this Tech Bulletin since last summer:

 

[Tony F]

That bulletin is dated June 2017. It was confirmed that there is a later Bulletin on the subject.

 

[silentservice703]

Let's see it!!!!

 

[Tony F]

Yes, anyone have access to it? Its locked up tight over here.

 

[Skintkarter]

MV have issued a new "MV Agusta internal service bulletin that MV dealers and service agents are following" with a new bleed procedure for the rear brake. It seems that the process has been carried out on some bikes with the process being filmed and sent to MV. The MV NZ rep advises that it is an internal document so cant be shared. But he is sorry. Surely someone will leak it!

The source of this was a discussion on the MV New Zealand facebook page where a few owners of 3 cylinder bikes were expressing frustration but the discussion has since disappeared from the page.

Tony, I removed the post from the NZ facebook page, but I'm still keen to hear from other people with rear brake issues on the ABS equipped 3 cylinder platform. I have a theory based on our experience with the bike, but am looking to collate further evidence. Cheers, Richard

 

[esq'z me]

Welcome to the family @Skintkarter !!! I take it you are part of the NZ mob...do you give Simon direction??

 

[Skintkarter]

Hi there and thanks. It's actually my eldest Son's bike and I've taken up trying to resolve the issue on his behalf. Yes we work with Simon here in New Zealand and he is being supportive in terms of getting the brakes bled under warranty, especially since the Dealer and Service Agents in Auckland have either folded (Red Baron) or relinquished or lost the franchise (Cyclespot). Our nearest Service Agent is now halfway down the North Island, or there are two in the South Island. As an engineer and based on our experience with the bike from new, I'm not at all convinced that the new bleeding procedure (which supersedes Service Bulletin #189) will offer anything other than a temporary benefit. I'm also unconvinced that the issue is related to heat soak, given that I looked at a brand new machine in the showroom at Cyclespot which had not been ridden, had 0kms on the clock and had exactly the same issue - namely no rear brake. It would have left with a solid brake pedal from the factory, yet somehow in transit and sitting it was now so full of air as to not operate. This is a serious safety issue, the bike would not pass our local WOF inspection and therefore would not be covered by insurance should an accident occur. I'm particularly keen to hear from anybody else with this issue on the ABS 3 cylinder platform - preferably off forum at this stage. Please feel free to PM me as I collate things. Thanks.

Cheers, Richard

 

[Tony F]

There have been a lot of members raising the issue on this forum Richard, hopefully some will contact you.

Was the new bleed procedure carried out on your son's bike?

A suspension specialist I deal with told me he had a spate of premature fork seal failures which he ultimately put down to a shelf life issue with the rubber deteriorating over time. He is now managing stockturn more closely and says the problem has gone away. Its hard to envisage this type of issue causing such widespread brake problems unless MV has been working through a huge stock pile of M/Cs. But mildly interesting.

 

[Skintkarter]

Hi Tony, no we haven't been subjected to the new bleed procedure yet. I don't think that it's a rubber deterioration issue. Our bike went into Cyclespot at 3000 or so KM's to have the issue investigated. They basically pushed the bike out into the weather each day for 2 months until a set of master cylinder seals arrived, which apparently they hadn't ordered... It was only at that point that they stripped the bike and pronounced that the master cylinder was stuffed (the diagnosis I had delivered the bike with after having the system bled by a service agent 4 weeks before). If it were a seal issue they would have fitted seals, but no they ordered a complete new replacement cylinder. You would only replace the cylinder if the bore was scored or corroded. My money is on the latter but unfortunately I didn't think to ask to see the faulty component. I have another MV owner delivering me a supposed new M/C in a few days time (need to cross check the part numbers) and I'm going to offer to pay for Dillon from TR20 to strip the master cylinder from our bike to inspect it, before anybody attempts the new bleeding procedure.