MV Agusta Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
255 Posts
Discussion Starter #1
Well, here's the story:
I've bought my Brutale last year in november and during the winter I've done some maintenance stuff so she can be ready for the start of this season and to check all those "weaknesses". Among other things, I found that the front wheel bearings were busted and, having the wheel off, I've noticed something interesting: front brake discs are not a pair, although they seem to be.
On the left says MIN.TH.4,0 mm and on the right MIN.TH.4,5 mm.:wtf:
I've measured the discs and now they are: left aprox. 4,3mm and right aprox. 4,8mm. Searching through the service manuals, it says that 910R Brutale has 4,0mm discs fitted as standard and 312R has 4,5mm discs as standard and both bikes seems to have same brake calipers.
So, my questions are:
1) The brake calipers on the 910R Brutale can work with any of the above brake discs size ?
2) How will those different size brake discs affect the braking on short term ?

What do you think?

Laur.
 

·
Registered
Joined
·
14,534 Posts
Laur;
i wouldn't worry about it......since they obviously aren't worried about Brutale discs being 0.5 mm thinner when worn out

F4 riders take note:stickpoke

you can wear your discs down to 4.0 mm before replacing them:drummer:
 

·
Registered
Joined
·
255 Posts
Discussion Starter #4 (Edited)
So what are you saying is that it doesn't matter that one disc is thicker than the other? Will have no negative effect on front braking?

Laur.
 

·
Super Moderator
Joined
·
22,072 Posts
So what are you saying is that it doesn't matter that one disc is thicker than the other? Will have no negative effect on front braking?

Laur.
No problem Laur, the calipers don't know what they're squezing.
 

·
Registered
Joined
·
255 Posts
Discussion Starter #6
I was worried about those discs and almost bought another set but didn't know if the 4,5mm ones were ok.
Now I can relax and enjoy riding it.
Thank you guys!


laur.
 

·
Administrator
Joined
·
20,107 Posts
The thicker discs can take more heat....the F4 is designed to have higher top speed than the Brutale. Thicker disc also adds weight. Other than that, like Donsey said, calipers don't care. Braking power will be equivelant. Sounds like someone damaged one disc on your bike and got a replacement that didn't match.
 

·
Registered
Joined
·
255 Posts
Discussion Starter #8
Yeah, I guess something like that happend and, because the 910R Brutale discs are not easy to find, he replaced it with one that looks like it but was not aware of the differences in discs thickness.
Does this means that a disc from 312R with MIN.TH. 4,5mm ca be worn till 4,0mm thick without any worries of breaking it ?


Laur.
 

·
Registered
Joined
·
14,534 Posts
Yeah they only crack at about 3.8mm
well, the Brembo warning was at 4.0 mm on Brutale discs, 4.5 mm on F4 discs so what was the problem?
could it be that you went 0.7 mm under the limit? you tell me

we raced 5,000km in a day, in endurance racing, rotors went over 2 years......

oops, they were iron rotors, not street, sintered stainless POS

oh, yes we didn't use flexy Brembo calipers or pads either:naughty:

just Lockheeds with racing metallic pads that were obviously full of a brass (?) alloy

the discs were always perfectly flat and shiny.....
just like on serious race cars......unlike the Brembos on my BMW GS

Donsy, go measure the line pressure in a hard stop......i did ~300PSI....on my Aprilia (as close as i could measure it while doing a hard stop)

cars run 1,000 PSI......think about it.....you have no tire contact patch area in comparison to cars
 

·
Registered
Joined
·
255 Posts
Discussion Starter #10
Hey guys, I'm bringing this thread up cause I need your knowledge again regarding my front brakes.
The front brake line fittings of my Brutale were realy rusty so I tried to clean them and give them that shiny look again. It worked but for a short period of time, now the rust has come back.
I've found some nice looking brake lines for sale but they are off from a 989 Brutale and I don't know if they will fit on my 910R calipers. The caliper end fittings looks the same like on 910R but I'm not sure if it's the right angle or the right length.
If anyone knows this details please let me know, so I can give her back some of the old brilliance.

Cheers,
Laur.
 
1 - 11 of 11 Posts
Top