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Discussion Starter #1
Maybe it's just my personal opinion, but I feel the rear brake on my 2018 f3 800 isn't the best,
Quite spongey, and needs pumped a few times to improve bite.
My local dealer says all MVs based on the F3 platform are the same, as the heat soak from engine and exhaust effect the rear brake master cylinder.

Has anyone else experience with this? And any advice on improving the rear brake?

Thanks guys.
 

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90% of F3 owners experience this.
The rear brake on F3 is a total nightmare to be honest.

Had my brake fluid change last week done by MV mechanic at dealer.
Rear brake is basically useless. Yes it brakes a bit but dont expect to lock rear wheel up.

Its 'normal' that it doesnt function propperly. Expect it to go bad real quick aswell.

*This counts for models with brake resorvoir up high behind side plate. Cant say how low mounted at brake pump work.
 

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Discussion Starter #3
90% of F3 owners experience this.
The rear brake on F3 is a total nightmare to be honest.

Had my brake fluid change last week done by MV mechanic at dealer.
Rear brake is basically useless. Yes it brakes a bit but dont expect to lock rear wheel up.

Its 'normal' that it doesnt function propperly. Expect it to go bad real quick aswell.

*This counts for models with brake resorvoir up high behind side plate. Cant say how low mounted at brake pump work.
Well that sucks haha
 

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Discussion Starter #5
The lower right foot operated wheelie control pedal works well enough to prevent looping out. Does it have any other function?
On previous bikes I liked to use the rear brake alot, mostly for slow/tight manoeuvres
 

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Yep, my 2018 Euro 4 model F3 (I believe they changed the location of the reservoir for these, according to MV dealer at service time) is also pants. I've bled it with about 500ml going through it a few weeks ago, it lasts for a day (great at first) but by the end presses to the floor faster than Osama bin Laden used to, with as much effect as Gretna Thunberg on turning Jeremy Clarkson into a Greenpeace ambassador.

Now, after use and when parking it up back in the man cave, I pump the brake and hang a 5L tin of paint off the lever. Seems to work, I just accept it as one of the idiosyncrasies of owning a non run of the mill bike. I know it's unacceptable, especially for the price, but hey ho. I can put up with it.

I will experiment with heat shields over the winter, and some fluid once suggested on here somewhere (Putoline I think, grade 4.0 but rated to 5.1??? I'll have to trawl the archives but it was 9nly in the last few months it was suggested)
 

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Discussion Starter #7
Yep, my 2018 Euro 4 model F3 (I believe they changed the location of the reservoir for these, according to MV dealer at service time) is also pants. I've bled it with about 500ml going through it a few weeks ago, it lasts for a day (great at first) but by the end presses to the floor faster than Osama bin Laden used to, with as much effect as Gretna Thunberg on turning Jeremy Clarkson into a Greenpeace ambassador.

Now, after use and when parking it up back in the man cave, I pump the brake and hang a 5L tin of paint off the lever. Seems to work, I just accept it as one of the idiosyncrasies of owning a non run of the mill bike. I know it's unacceptable, especially for the price, but hey ho. I can put up with it.

I will experiment with heat shields over the winter, and some fluid once suggested on here somewhere (Putoline I think, grade 4.0 but rated to 5.1??? I'll have to trawl the archives but it was 9nly in the last few months it was suggested)
Amazing reply ever.

Tbh I've already ordered an aftermarket slip on exhaust to try and defect some of the heat, and while I'm in about that area I might see what I can do with some heat reflective material.

I'll post back in the future with my results.

But I totally agree... For the price you pay for a new f3 a working rear brake would be lovely
 

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I can lock up my rear wheel with the brake pedal. Is it particularly aggressive? No, but it will make the tire skid if I try.

The front brake is the primary agent for slowing down from speed. Rear brake is really only a chassis stabilizing agent or anti-wheelie device. Unless you are on a Harley or other heavy weight cruiser.....

If your brake fluid is good, your system is bled properly, and you have good brake pads....the rear brake will work as it should.
 

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yup. totally useless brake on the rear. on my 2015 f3, my rear caliper, just out of nowhere, cracked in two while i was out on the track and puked its oil all over my rear wheel, despite like never using the rear brake! put a new brembo on and it's just as useless...
 

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yup. totally useless brake on the rear. on my 2015 f3, my rear caliper, just out of nowhere, cracked in two while i was out on the track and puked its oil all over my rear wheel, despite like never using the rear brake! put a new brembo on and it's just as useless...
That could have been nasty.

Last sentence made me smile - comforting to know 8m not the only one exasperated with it.

I took a screen shot of the conversation a while ago about the fluid, I will also give this a go over the winter, along with heat shield experiments.
 

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The whole heat thing is BS....

My 1199 Panigale, has the reservoir right next to the engine, and if you have ever ridden one of these bikes you know how hot they get.
Also the brake master is not far off from the massive rear header.. so again i call BS.
but i don't have abs on the bike.


I would think if you have ABS this is more of the module taking away power to the caliper, and giving crap lever pressure, the bike does this to the front as well.
Or it could very well be the brake master itself, not sure which version it is..
 

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Discussion Starter #13
It's all BS haha,

Well if anyone finds a solid way to improve the rear brake, let us know.
 

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It's all BS haha,

Well if anyone finds a solid way to improve the rear brake, let us know.
Swap pads, dump the ABS if you have it. If i can find the time i will see which brake master is on the back, compared to say my Panigale, which had stellar rear brakes (heat soaked and all).
 

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That could have been nasty.

Last sentence made me smile - comforting to know 8m not the only one exasperated with it.

I took a screen shot of the conversation a while ago about the fluid, I will also give this a go over the winter, along with heat shield experiments.

To update on this, I can say that the new fluid didn't work for very long. The rear brake on my F3 is almost completely gone again :)
This leads me to probably pursue getting proper rear-sets from Walter-Moto that the WSBK F3 bikes are using, which mounts the master cylinder to it, instead of the engine.

Someone is saying that the heat thing is bullshit, I'm not too sure before having tried to move the entire system.

Heres my thread by the way:
https://www.mvagusta.net/forum/45-f3/243421-rear-sets-rear-brake-master-cylinder-mount-2.html#post2602707
 

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My rear brake is great when I first start riding it, but fades to nothing throughout the day. The more I use it, the faster it fades so if I only use it a handful of times, at the end of the day it's still useable.

No problems whatsoever with the front brake, that's solid all the time (just how I like it). I have the ABS set to level one, but can't honestly say that it's ever kicked in, or not that I've noticed while riding. When I first got the bike, and while running in, I did experiment with the ABS by stomping on the rear brake and feeling the ABS kick in. Just wanted to know what it felt like as never ridden a bike with any electronics before.

Interesting to note that Sneaky Owl didn't have any joy with the fluid change, I obviously missed the update on the thread.

Trouble is, I also like my MV rearsets so reluctant to change. I'll just put up with it for now, and as bike is away for the winter. I'll experiment with heat shields, possibly relocating the reservoir, fluid changes...etc...
 

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Here is why I believe the heat reason is not valid for the three cylinder bikes: the rear brake master cylinder is mounted just adjacent to the oil sump. The exhaust is located in the other side of that sump. The sump is relatively cool.
On the 4 cylinder bikes, the rear brake master cylinder is mounted directly adjacent to the exhaust and the catalytic converters which adds a ton of heat.
By example, my ABS 2015 B3 800RR brakes were bled and solid. The bike was put away in storage for 11 months. The bike had not been started, yet when the rear brake was actuated it was air bound...after simply sitting still. A quick bleed at the caliper and back in business
 

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Maybe it's just my personal opinion, but I feel the rear brake on my 2018 f3 800 isn't the best,
Quite spongey, and needs pumped a few times to improve bite.
My local dealer says all MVs based on the F3 platform are the same, as the heat soak from engine and exhaust effect the rear brake master cylinder.

Has anyone else experience with this? And any advice on improving the rear brake?

Thanks guys.
One thing I did do that helped was reposition the lever so it sits higher, I put it as high as it will go so it's almost touching the fairing. That has done nothing for the performance but it now starts working where I like the lever to normally sit.
 

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It is definitely not a general Italian thing, the F3 is „special“ in that regard. My 2015 F3 had been a nightmare in that regard, freshly bled it was acceptable at most and did not last long. The F4‘s rear stopper is significantly better, but still mediocre compared to e.g. the RSV4 (which is ok for a superbike taking into account that the rear brake on a sports machine is more used as a stabilizing factor).
It is strange that MV repositioned the fluid reservoir‘s position on the E4 models and this is still an issue. Supports Silent‘s analysis that heat is not the root cause. A thing to resolve on the next update of the F3...
 
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