brake lever too firm (!)

[superawesome]

I know this sounds weird. The brake lever for my front brake is too firm. So it applies too much pressure too fast. Of course this is not my opinion, but the inspector at the roadworthiness check said that. So I gotta fix it.

Bike is a 1978 GS1000 with a standard brake (two single-pods), brake pads are fairly new (2 years old, maybe 2500km). I did switch to steel-braided brake lines 2 years ago (and yes, it was softer before, as it said '1978' on the old brake lines). I did not rebuild the calipers yet (would have done that if I had too little pressure...). I maybe have about 15mm from very light braking to full force (measured at tip of lever). I know it is not much but it did not really bother me, as brake power is good.
Since there is nothing to alter at the lever itself, how could I lower the pressure?

I still have the old brake lines and could put them in for the re-check, but then I want to avoid unnecessary work...

Thanks

 

[fastbysuzuki]

First can you clarify, is this inspector saying that the brakes are pulling up to sharply or grabbing/snatching. Or there is exesive Lever movement and has a spongy feel to it?

Reading through what you have written and the improvements you have made i.e. New brake hoses etc I am struggling to see a problem unless I am miss reading something
what are you meaning by (two single pods)?

Just a thought seeing you are in Basel are you a member of "Top Secret" ?

 

[superawesome]

Haha, while I enjoy the annual Fasnacht, I am not an active drummer. How do you know of Top Secret?

Should be 'single pot', not pod. My bike has two discs with a single-pot caliper each.
The problem (apparently) is that it brakes too sharply. (I also don't see a problem, but the inspector does)

 

[cowboyup3371]

I'd say find a new inspector

 

[fastbysuzuki]

Well cowboyup3371 beat me to it, personally I would take it to another place to have it tested I would bet it will pass with no problem.
on occasions testers have been pulled over something they have previously passed by the governing body when that happens the tester becomes very very picky for a period in time until the nervousness wears off and things return to normal.

How do I know about Top Secrect I watched them at the Edinburgh Military Tattoo 2012 been a big fan since then

 

[superawesome]

I'd say find a new inspector

Would love to, but it doesn't work like that here (anymore). I have to go to the exact same place again. I can be lucky to have another guy at the re-check, but might end up with the same bloke...

 

[GregT]

If the inspector wants less initial bite, an old race trick is to trim the pads. If for instance a rider had an insensitive foot as a result of an accident, you'd cut the rear pads back to a narrow strip of material on each so that he couldn't lock the rear inadvertently.
It would work on the fronts too. I'd cut the moving pad back a little and try it. The moving pad will have the bigger effect IMO on sliding calipers.

 

[Baatfam]

I really, really think we are missing something here. I have never met a GS with brakes that work too good. Not original brakes, anyway.

 

[roeme]

Eeeh...while I did manage to rebuild one my GS front brakes to a hefty bite; that really shouldn't bother an inspector at all. You managed to get an idiot (which is all too common here in Switzerland).

Maybe bleed the brake a little bit.

Other than that I suggest you do the same thing the last time one of those twats (young greenhorn inspector) wanted to take my bike off the road: I grabbed a senior inspector and kindly asked him for a second opinion.

Buuuuuuut....15mm from none to full force (i.e. locking) _does_ seem too aggressive in my opinion as well. That is not even the diameter of the nub at the end of the brake lever. It doesn't leave a lot of wiggle room for changing conditions (i.e. heat or water buildup) to not lock up the brakes inadvertently.

Not sure about your riding style. Might be fine for puttering through the city; but for me that would be way too sensitive.

 

[fastbysuzuki]

Eeeh...while I did manage to rebuild one my GS front brakes to a hefty bite; that really shouldn't bother an inspector at all. You managed to get an idiot (which is all too common here in Switzerland).

Maybe bleed the brake a little bit.



Buuuuuuut....15mm from none to full force (i.e. locking) _does_ seem too aggressive in my opinion as well. That is not even the diameter of the nub at the end of the brake lever. It doesn't leave a lot of

Not sure about your riding style. Might be fine for puttering through the city; but for me that would be way too sensitive.

Bleeding will make it better (if there is any air in system)

15 mm Lever travel is what I would say is a good setup (mine has about the same)

lever travel is not not an issue, as previous post states these brakes are 1980 in comparison to a modern bike they are no where near the same.

The issue here is the tester is a complete moron, and personally I would not consider any bodge ups or alterations to make the system worse (why would you)
can you not ask for a different tester?

 

[Gorminrider]

It can help temporarily to release a bit of fluid from the calipers but another thing I have found was the caliper "bolts" the system slides on can get sticky..(I can't think of a name for these "bolts") ..particularly: on my caliper slide-bolts, one of them has a kind of rubber collar and certain greases don't "agree" with it, despite being "safe for brakes" (hi-melt temp is how I interpret this..?)
or just do the calipers..eg: the piston can get rusty if the boot fails..the more your OLD pads wore down, the more the piston was extended to the weather...when you simply replace pads, that rusty part gets pushed back onto the seals...
But then there's the hydraulics themselves..ie: did you replace the master cylinder? a bigger bore will move more fluid faster so brake lever travels less...

or, your inspector is used to car brakes....? He'd likely fail some of my bikes too..all mine have slightly different components on the front discs and ALL are different to use...

 

[Guest]

How do they quantify and measure brake lever firmness? Is there a spec?
Did this "inspector" ride your bike? Did he have a suggestion for a "remedy"?

Rather than challenge him its probably best to just crack a bleeder and introduce a little air into the system just to pass inspection. Bleed it out after passing. Its always a crap shoot opening any kind of discussion with police , border guards , security guards and inspectors. (especially if you've been drinking)

BTW
My 1150 is like that , I think the brakes are more about applied pressure than lever travel, (I like very little). Modulating brake pressure seems to come quite naturally. My 1150 still requires a lot of effort at the lever compared with modern bikes, but there is not much lever travel. ( until the fluid gets old )

 

[bwringer]

Yep, the inspector is a moron.

If you're stuck with him, crack a bleeder and let in an air bubble. Bleed to calibrate your pet air bubble to taste so you get more travel yet hopefully you won't kill yourself on the way to the inspection point.

Then bleed it normally once you get the stamp of Official Moron Approval.

 

[superawesome]

So I phoned them up today and asked for the "Hallenchef" (senior inspector) to "ask a technical question". When I got him on the line, I said I was confused with what the tester said about the brakes, and that I'd like to get an idea of what I can do to meet the regulations (as I even phoned the manufacturer of the brake lines who had no real suggestions (after stopping to laugh loudly)).
He agreed me to come along and him taking a look at the bike. So he took a ride, talked to another (more senior) guy, who also took a ride (seems like the whole station wanted to get a ride on an old GS ).
The latter admitted that the problem is that the front wheel tends to block too fast, but then said that there is no technical solution for that, so it should be ok to pass the test. He suggested that I should learn how to deal with a blocking front wheel when braking.
All in all it was a fair treatment I must say.

I still have to go for re-check, but the brakes are not a problem anymore. Still have to focus on replacing chain and sprockets now, and then it should be good to go.

Thanks everybody for suggestions - case closed

 

[salty_monk]

My guess is that if the calipers are not rebuilt you could have stiff/sticky seals.

All pistons retract a little away from the rotor when you let the lever go - I suspect your old seals are holding them out close to the rotor & so no "work" is being done / lever travel being used to actually get them back to the rotor surface.

You may find your wheel doesn't spin so well if you raise the front end and spin by hand.

The only other time I've experienced something like this is when a set of pattern (Galfer from memory) brake pads (on the KLR) were slightly oversized & were hanging up in the caliper carrier. That had the same symptoms as above. A file on the edge of the backing plate soon sorted that out.

Of course it could also just be the inspector doesn't know what he's looking at as previous suggestions....

 

[superawesome]

Thanks for the note, Salty Monk

I was actually surprised how well the front wheel spins but you might still be right with the stiff seals. I will rebuild the calipers anyway (using one of BassCliff's fine tutorials) since I did order all parts a few months ago, but did not have time yet. PO was a cheapo and who knows what he saved on when doing the job?! I found all rubber parts needed replacement on the bike so far, would be a surprise if the calipers were any different...

 

[fastbysuzuki]

Hi, glad you have sorted out your problem regarding the brakes I think I may have come across a video of the tester that failed your brake failing his last test.