Braking system

[getagrp1k]

I want to remove or deactivate the Linked part of the braking system, I cant stand it. I cannot tighten up my line if need be while riding the twisties, will trade for non abs if worse comes to worse. It looks like i need a new right caliper since it has 2 lines going to it and the fluid it blocked by thru passage to the other side, not sure about the rear.

 

[charismaticmegafauna]

I think you're screwed? At least in the near future...

The market has spoken: and they all want a computer to do their braking.

[sarcasm]You can't possible be smart enough to know how much brake to apply when and where -- only computers can do that..![/sarcasm]

Seriously..., I think most riders who take all aspects of their riding as critically important -- will just need to adjust to (many of) the current motorcycle offerings.

Or, restore and up-date a pre-computer-controlled bike?

 

[wfooshee]

I can't comment on what you feel while riding, of course, but you might be making more of the link than actually exists. There is no link from front to rear, only from rear to front. The link is to only one of the four piston pairs, and has a threshold of pressure that must be reached before the link actually works. Light to moderate rear brake, no link. Heavier rear brake, then the link opens. There is no through passage at the front to other pistons; the line from the rear goes only to that one pair of pistons, and that pair does not work with the front brake lever.

 

[madmike2]

IIRC, the back must be applied fairly heavy to activate the front piston though I don't remember the percentages. It could be they are exactly linked but I'm old and my brain doesn't remember.

As an experiment, why not plug the front caliper and cap the line to that piston, then ride the bike. That test ride should tell you if the front is activating and if that is the issue while trail braking into a corner.

Should you decide to replace the front caliper, the forks are different from Gen I to Gen II so I don't believe the calipers will swap.

Edit: A clever person could build a manifold at the caliper and run a secondary line to the link piston rather than having a machine shop bore a passage.

 

[bramfrank]

Madmike2 is correct - the fact is that the rear brake (which by all accounts should be used very, very sparingly) is linked to one of the front pistons, but only in proportion to the rear and only after a threshold has been reached.

Indeed, pulling the line to the front and capping it will eliminate the link and, with a banjo bolt and appropriatelky made cable, you could put that 4th piston to work with the front lever.

However, perhaps you need to look into suspension or alignment issues - the link is VERY unobtrusive and you are the first person in the 4 model years that the brakes have been linked who pretty much even noticed that the feature is there..

 

[UselessPickles]

I want to remove or deactivate the Linked part of the braking system, I cant stand it. I cannot tighten up my line if need be while riding the twisties, will trade for non abs if worse comes to worse.

Are you complaining because you know for a fact that you have experienced undesired braking behavior caused by the linked braking system, or are you just theorizing that it will happen? I've never heard anyone complain about the linked system on the FJR actually interfering with desired braking behavior. I only see people complain that they don't like the idea of linked brakes because [insert reason here], but they haven't actually ridden an FJR with linked brakes. If you are using the rear brake hard enough in a corner to activate the linked brakes, then maybe you're just going much too fast to begin with to the point that you'd just lock up the rear tire if it was not a linked system?

Or, restore and up-date a pre-computer-controlled bike?

The linked braking is not computer controlled. Maybe you're thinking of ABS.

I just looked at the service manual, which has a section explaining the linked brakes. There's 2 valves involved. A "metering valve" prevents any pressure from the rear brake pedal from being applied to the front brake until a certain threshold is reached, then a "proportioning valve" comes into play after the metering valve opens, and it splits the brake pedal pressure between the rear and front brakes. The valves are arranged in such a way that only the additional force beyond the threshold of the metering valve is split between front and rear. When you exceed that threshold, rear brake pressure does not suddenly drop to help apply the front brake. As you press harder, you just won't be increasing rear brake pressure as much as before the threshold because the additional pressure is split between front and rear. Likewise, the front brake won't suddenly grab as you apply pressure to the brake pedal. And yes, the rear brake pedal only activates one set of pistons on the right front caliper (...only after the metering valve opens).

Basically, the rear brake pedal acts like a normal unlinked brake system until you press it hard. How hard? I dunno. But I've seen reviewers comment on how it is a well-executed system that allows you to use the rear brake for low-speed maneuvers and trail braking in corners.

From the manual:

The operation of these two valves ensures that the braking feeling of conventional brakes is maintained when a small amount of force is applied to the brake pedal, such as when making U-turns, and prevents early locking of the rear wheel when a large amount of force is applied.

 

[SkooterG]

You should have posted this on a Friday!!!

I would really like a detailed explanation on how the linked braking is causing apparently poor handling attributes.

 

[FJRBluesman]

Just forget about your brakes and use your feet.... like Fred Flintstone.

 

[madmike2]

You should have posted this on a Friday!!!

I would really like a detailed explanation on how the linked braking is causing apparently poor handling attributes.

Which is the basis for my suggestion about the experiment.

Since I'm not the one riding nor am I a witness to what is happening I am left to aid in dispelling any reason for handling/cornering problems. The experiment I outlined above would eliminate a suspected braking problem and should cast light in another direction.

1.) Suspension

or

2.) Weight of the FJR being 200 lbs. above what he's used to riding

or

3.) Technique (see number 2 above)

It will be interesting to follow the process and hear the end results/conclusions.

Maybe he could find someone locally that has a non-linked brake bike and swap, however, if corners are being charged hard enough that a vast amount of trail braking is required to correct the cornering line, finding that "other" owner might prove a difficult selection problem. :blink:

The above is merely my humble opinion and not in any way based on fact.

 

[jpcfjr]

I didn't realize my FJR had brakes. Interesting... :blink:

 

[madmike2]

I didn't realize my FJR had brakes. Interesting... :blink:

Yes, well, there are those who actually twist the right grip-thingy and find they need more than engine compression to slow for the rapidly approaching bend in the road.

They're usually the same owners who find suspension upgrades to be a fine addition to their riding school and track day curriculum.

Er...uhm...YMMV. :blink:

Uh corse....theyers allays "Flipper's" owner.