How to prevent boiling out your rear brake....

[Rox Lemans]

 

Viola. Guzzitech has a custom bracket to fit a rear 4 piston caliper onto your v11 Sport. Another plus is the bracket has a better wheel spacer thanot what came from the factory.

So far I am loving it but need to get used to it because the rear now has some serious bite.

[Kiwi_Roy]

That looks great!

 

Can you provide a link to the parts

[Lucky Phil]

If you're boiling the rear brake fluid on your V11 then you have either an issue with the rear brake system maintenance wise or your riding style. The std rear setup is entirely adequate.

Ciao 

[andy york]

Sorry, I have to say it. 

Adequate for what ? Normal street riding,yes, its ok. For anything else, track, mountains, or any form of "hard" 

riding it is not adequate. It is to small and does not have enough capacity. There is also a lack of airflow in its current position.

Been wanting to upgrade for years, Life keeps getting in the way 

 

andy

[Kiwi_Roy]

The small square pads last no time at all, mine were down to the metal when I got the bike. The ones shown here should at least last as long as the front.

 

 

Sent from my shoe phone!

[GuzziMoto]

It is not a mod that I would do, but it ain't my bike.

I don't agree with Todd on everything, including when he proposed that set up. But if it works for you, congrats. It is always nice to address an issue you have with your motorcycle.

[Scud]

When Chuck, Rox, and I rode the Santa Monica Mountains recently (with subsequent visit to Todd's GuzziTech shop in Malibu), Rox did lose rear brake pressure (and it came right back after cooling). Todd said he frequently loses rear brake pressure in the mountains. There are some seriously long and steep climbs/descents.

 

Riding style is probably part of it. I tend to go heavy on the front brake and think of the rear sort of like an emergency brake. I've never lost front or rear brake pressure. But I couldn't keep up with Rox while descending Tuna Canyon, and I'm pretty sure Todd would leave us both far behind.

 

I posted this image before, but for context, here's Tuna Canyon: an 1,800 foot drop in 4 miles. Single-lane, one-way, downhill only - no risk of encountering opposing traffic.

 

 

This kind of terrain will give any bike's brakes a workout - and send the V11's oil sloshing backward during full-throttle ascents. (see Roper Plate for solution to that)

[czakky]

Never had that problem with the rear brake myself. But I don't encounter 1800 foot drops on a single lane track very often either!

Thanks Rox/Scud for the info.

[docc]

Right? 1800 feet in four miles!

 

Even with a four piston caliper, the V11 rear is positioned low in the spray and "upside down." No matter what, it is probably desirable to remove it regularly (every tire change?) and turn the nipple to the top for bleeding, as well as taking time to move each-and-every piston in and out until they all move freely.

 

As the original fitment caliper only has the two pistons, it is critical to make sure they stay moving freely and evenly. As has been said, the pads have very little contact area and the rear brake is minimal at best. Even staying after mine, they only last about 10,000 miles.

 

Really interesting fitment, the four-pot to the rear!

[Lucky Phil]

You know in 45 years of continuous riding and bike ownership, sports riding, track riding,dirt riding and literally dozens of bikes from BMW K100's to RC30 Hondas and the present fleet of 1198 Ducati,V11, GSXR1000 track bike, SS Ducati etc I have never replaced a set of rear brake pads due to wear.The only time I have had to deal with overheating rear brakes was with racers due to unconscious dragging of the brake (they all swear on a stack of bibles they don't do it but that was always the reason)

The only use I have for a rear brake is to hold the bike on a slope at the lights and tighten the line if I'm running a little wide in a turn and don't really want to get fully off the throttle. 

Don't ever recall using one on any of my sports/sports touring bikes for actually stopping or slowing.

If you were talking cruisers then I might see the reason but on a sports bike...sorry I cant see the need.

BTW 1800' in 4 miles is not a huge gradient 8.5% average or so. About what it takes to get the attention of a serious cyclist.

My regular ride used to be 2230' in 7.75 miles or 5.4% and I never even considered brake fade as likely, that's without using the rear.

Ciao

[footgoose]

As you noted in a previous post, Phil, it comes down to riding style. In my 50 years of motorcycling, I've owned a few variants as well. Never ridden on a track though. My first self inflicted crash was a result of an emergency stop at a wet and loose pot hole, using the front brake only. I was quite young and really only had a helmet on because it was raining. Landed right on my head and only twisted an arm. Ever since, I've been a fan of the rear brake, and not just in the wet. It gets roughly 10 to 25% of combined pressure at all my normal stops. And just short of skid on wet or gravel. My V11's and the DR650 seem to eat rear pads faster than others I've had. About every tire change. The V11 oem rear is sufficient for my use, but I will use it. I don't believe I'd be as 'lucky' as you only using the front.

[Lucky Phil]

 

Here's a picture of the rear brake setup on my old 888 Corse. The disk and caliper carrier were machined up by me and its effectiveness was minimal, just how I like it.

Look at any newish superbike/sportsbike rear brake setup and you will see the priority they put on rear brake power and stopping ability.

The question to ask yourself is why....the answer is that they don't really expect you to use it for stopping which leads to the obvious question for those riding sporting motorcycles and wearing out/overheating their rear brakes...does my riding style need reviewing?

 

 

 

Current V11 setup

 

Ciao

[Scud]

Seems that for riders who do use the rear brake regularly, the 4-piston caliper would be helpful. More surface area = longer pad life and more heat dissipation. 

 

I'm switching to DOT 5.1 fluid for all brakes as extra insurance. It has a higher boiling point than the DOT 4.

 

To the riding style point: the shortest stopping distances are recorded when the bike does a mild stoppie - with the rear wheel in the air. Obviously, the rear brake provides 0% of stopping power if there's no tire contact to the street. But these tests are done in controlled environments. On the street, with potential potholes, sand, oil, etc. it makes sense to use some rear brake. I'd much rather risk locking up the rear than the front.

 

To Andy's earlier point about regarding mountain riding, I do worry about overheating my front brakes in the mountains, and it's not just the grade of the road. For example, the orange section in the attached image represents a 900 foot descent in 1 mile. That's a 17% grade. The entire highlighted route represents a one mile vertical descent in 15 miles (that's net and excludes all the in-between ups and downs). It's not just the steepness, but the corners (where I do some trail braking) that concern me - and the frequency and duration of them. This kind of twistiness goes on for 100 miles. So I push it a while, then take it easy a while - thinking that this will cool the brakes. 

 

 

BTW as for another preventative technique re rear brake:  I find that the engine slows the rear wheel plenty and I don't need the rear brake much.

[sp838]

Is that a Galfer wave rotor?

[Bruce Reader]

does the bracket adjust the space from the wheel to the swingarm (lhs) ?

Where is it on his site ?

 

Cheers

 

Bruce