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Hey guys, the rear brakes on my F3 800 seems worthless- are you guys experiencing the same level of "ineffectiveness' with your F3 rear brakes?

My setup is stock and has allot of downward travel but the stopping power is almost non-exsistant- any workarounds?

(I know most of the stopping power is from the front- but I still want effective rear brakes.)
 

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I have had three F3's over the last five years and the rear brakes on each one have been useless.

The only time that it is effective, is after being bled correctly, it will then last only a few hundred miles.

There have been many recommendations on how to improve the problem, but as far as I am aware there is is no real cure:shocker:
 

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The rear brakes are only useful for chassis stabilization or wheelie control, they were never meant to stop you....if they were that strong you would be constantly locking up the rear wheel or activating the ABS system (if equipped).
It's not just MVs....other high performance sport bikes also have relatively weak rear brakes.
If you absolutely stand on the pedal it will lock the rear brake. Try it.
That said, this isn't a Harley.

The master cylinder location is very close to the exhaust system and related heat. High quality brake fluid and proper bleeding will ensure the best performance possible.
 

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One other thing to do is to install a heat insulation material between the exhaust and the rear master cylinder.
 

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MY reak brakes do stop the bike, but I am unable to lock up the rear wheel no matter how hard I press on lever.
This wonders me when I wanna take of the rear wheel nut. Is it even possible since from factory the nut is torqued harder than 220nm (im geussing harder since everyone struggles big time to get the wheelnut off)
 

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MY reak brakes do stop the bike, but I am unable to lock up the rear wheel no matter how hard I press on lever.
This wonders me when I wanna take of the rear wheel nut. Is it even possible since from factory the nut is torqued harder than 220nm (im geussing harder since everyone struggles big time to get the wheelnut off)
The difficulty removing a rear wheel nut is not really due to overtourqing. The aluminum nut and the steel axle develop galvanic corrosion and it only takes a very little amount of corrosion to create a lot of stiction causing difficulty removing the nut. The cure is to use an anti-seize compound on the threads of the axle, thus eliminating the corrosion issue.

Now, back to the rear brake: The rear brake has plenty of power to keep the rear from moving when undoing the nut. A properly maintained rear brake will stop the bike, albeit not as efficiently as two 320 discs being clamped by four pot calipers as on the front. That is not the design of the rear brake. As has been mentioned by others, the rear is for chassis stabilization and hill holding.

The torque value holding your rear wheel nut is 162-177 ft-lbm. This is not extraordinary.
 

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The F3 800 is meant to be ridden as a sport bike. I do not use the rear for anything while aggressive riding in the twisty stuff. Even if I did the back wheel is off the ground and useless as a brake anyway.

What I do use it for is:

1) During wheelies as a safety precaution. I don't even actually use it here. I do it all with my throttle hand.

2) Sometimes when at a light depending on if I want to make my upper body upright. This also depends on being in neutral and which foot is on the ground. Its just a way to rest if I need it.

3) Removing rear wheel. I use a breaker bar with me on the seat facing backwards. Left foot on brake and both hands pulling breaker bar towards me.

Make sure though that you have no air in the brake. Make sure it isn't bottoming out. Make sure your rear reservoir is actually full. The bladder inside can fool you into thinking it is full.
 

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To all kind gentlemen who never use their rear brake: "how to you back it in" without using the rear brake?
Asking for a friend...
 

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To all kind gentlemen who never use their rear brake: "how to you back it in" without using the rear brake?
Asking for a friend...
You pitch it in like a dirt tracker..... It's breaking the rear tire loose from steering action, not locking up the rear wheel brake. Ever done any flat track racing?

Should add a note...very aggressive rear pad material will increase rear brake power...and eat up the rotor. :D
 

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Right esqz'me

Just take a look at some videos where the rider has the right foot hanging off the bike at entry. They are not on the rear brake at all obviously... but the rear is stepping out. The left leg adds to the stability of the rear and can be used to pull the rear in line physically. I don't back in the bike on purpose by the way. I spend more time on the street where entering hot is not wise. No run off areas. I am more aggressive on exits than entries.

I also don't typically shift mid turn (race pattern or not). So both my feet are on the balls on the pegs. This allows me to do a switch back with ease. No worry of toes hitting the street. No loss of stability in the chassis.

FYI... I did adjust the rear brake to have less movement before engaging. There is a clip and lock nut mechanism at the master cylinder. Don't over do it though... or else you'll be dragging the rear brake.
 

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I was of the same opinion about the rear brake being ineffective so as quick test I disabled ABS and the slightest pressure on the pedal locked up the rear. It not that the rear brake is ineffective it's that there is no weight and traction for the tire to slow you down.

Just my two cents.
 

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Right esqz'me

Just take a look at some videos where the rider has the right foot hanging off the bike at entry. They are not on the rear brake at all obviously... but the rear is stepping out.
Have you ever heard of a Thumb Brake?
 

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True, but not needed for rear to step out.

https://www.motorbikefans.com/mm-jl-interested-thumb-operated-rear-brake-motogp/

Wanted to add that with the reverse engine crank the tendency for the rear to lighten up under braking is reduced. My previous bike would step out more often and easier. The 3 cyl platform stays more planted under braking. I have engine braking set for sport(less engine braking) and the slipper adds to the wheel staying connected with the road and not sliding.

Have you ever heard of a Thumb Brake?
 
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