front brakes feel grabby

[svsteve]

97 std. 30000 miles. My front brakes don't work as smooth as they used to. They feel kind of like they are not working then they grab and will slow me down. I tried changing the fluid but no better. Is there a rebuild kit available for the calipers that anyone knows of? Could it be master cylinder? Any thoughts appreciated. Thanks. Steve

[gordonv]

Air in the system.

How did you do the job?

[svsteve]

no air in lines. they were grabby before changing fluid.

[The emperor has no clothes]

When was the last set of brake pads ? And has any fork oil got on them ?

[svsteve]

brake pads are fine, no fork oil on them. I feel it in the lever when I squeeze. Feels like something is hung up then lets go.

[hubcapsc]

I think you're on the right track with the rebuild.

A couple of sets of seals, some new brake shoes, pop out the pistons
and clean them up like new, clean and grease up the pins the calipers slide
on, and clean (don't lube) the pin that goes through the shoes...

Valkyrie front brakes can be really good.



-Mike

[98valk]

remove calipers.  extend pistons. clean outside of pistons with 0000 steel wool. air blow clean, wipe down, air blow again. wipe again, re-install calipers.  use DOT4 LV.  has higher wet boiling temp (allows 3-4 yrs replacement in most cases vs 2 yrs for DOT4) and will give a more consistent firm feel over a wider range of temps.

[JC19]

I had a similar situation recently. And yes, a rebuild is a really good idea. What I found to help me was a little lube on the plunger that the lever pushes against. The rubber seal seams to be slightly deteriorating.

[knockdolian]

If your calipers aren’t binding I’d be looking at the master cylinder.

[Earl43P]

I disagree and it's a simple fix.

The bushing that the front handle presses upon to actuate the master cylinder piston needs a little (Lubriplate) lubrication or replacement, and then lightly lube the contact point. This is an inexpensive part and a common wear item that produces this exact symptom.

You may also need a new front brake lever because the nub that presses that bushing also wears.

Edit: I see that JC19 covered that!

[Ricky-D]

Consider that the brakes are performing as they should.

The brakes on the Valkyrie are the best performers found on most all motorcycles. The brakes are top notch.

Grabby brakes, heck, that's what they are supposed to do. Grab that rotor and make it stop turning.

You can go to any extreme replacing all the components and find there is no change because there was nothing wrong with the brakes to begin with.

It the brake pads are in good condition as well as the rotor, you are good to go.

And keep in mind, the brake pads can be made of many different materials, all of which have different braking characteristics. Some more "grabby" than others.

***

[Bagger John - #3785]

I think people are getting "grab" and "drag" confused.

If the brakes drag after application, a caliber rebuild is definitely in order. If - on the other hand - you cannot linearly apply the brakes, I'd have a look at rotors and pads...followed by the lines.

[Jess from VA]

One of the things I do that helps my brakes a lot (besides servicing them at tire changes and rear end lubes) is this:  when I wash my bikes, I liberally spray wheel cleaner or S100 all over the brakes/calipers (and wheels) and scrub them up real hard with stiff bristle brushes.  Then rinse liberally (and I blow dry with a Stihl leaf blower, before towel dry).  You must not let mild corrosives (wheel cleaner and S100) dry before rinsing.  This always gives a noticeable improvement in brake function (but it's not new pads).

There are all kinds of spray mag wheel cleaners at the auto parts.

S100


Even though S100 says it is total bike cleaner, I do not use it on my whole bike or any paint.  

I wash the bike in sections, from the bottom up, and will use S100 on the brakes, tires, underneath and engine.  Collection of stiff bottle brushes goes into tight spots.  I change the (hot soapy) wash water after doing the crummy bottom, before doing the top.



When servicing my brakes, I clean them with gun cleaning bore cleaner and old brass/bronze brushes on a pistol rod.  Especially on the pushed out (but not all the way out) pistons.


OR this:




 

[98valk]

S100


Even though S100 says it is total bike cleaner, I do not use it on my whole bike or any paint.  

I wash the bike in sections, from the bottom up, and will use S100 on the brakes, tires, underneath and engine.  Collection of stiff bottle brushes goes into tight spots.  I change the (hot soapy) wash water after doing the crummy bottom, before doing the top.

hey Jess, spraynine is the same product as the S100. works the same, smells the same and a lot cheaper and can be bought in a gallon size.  first time I used S100, the smell hit me and I pulled out my old bottle of spray nine. same stuff.

https://www.spraynine.com/

[Jess from VA]

How about that?

Spray nine (from outer space).   

[svsteve]

Good advice JC19 and Earl43P. Took a look at the lever and plunger, added some lubrication and its as smooth as ever. I gotta get something better to use than wd40, but it solved my issue. Thanks Guys

[Bagger John - #3785]

I gotta get something better to use than wd40

That stuff isn't a lubricant per se. It's a "Water Displacer". (See if you can spot what I did there.)

Its lubricant properties are coincidental, and since WD-40 is a solvent it'll flush out and remove any existing lubricants - such as grease. This tends to make sticky or binding matters worse in short order.

Look for some LPS-1. I use a mixture of it and white lithium grease, applied to the lever pivot bolts and plunger barrels.

[Skinhead]

Good advice JC19 and Earl43P. Took a look at the lever and plunger, added some lubrication and its as smooth as ever. I gotta get something better to use than wd40, but it solved my issue. Thanks Guys

I use belray grease on my levers and pivots, if you don't replace the bolt, and it is worn, (grooves), you can rotate the bolt so that the smooth part of the bolt faces where the lever pivots, and lock it in place with the jamb nut on the bottom of the pivot bolt.  Order replacement bolts and replace them next time they show signs of wear.  BTW, I disagree with RickyD on his statement.   My brakes were doing the same thing, Lubing the levers and rotating the pivot bolt, fixed the issue.  Both brake and clutch levers are often overlooked maint. items, like door hinges on cars.  No lube=wear.

[RonW]

Both brake and clutch levers are often overlooked maint. items, like door hinges on cars.  No lube=wear.

Two days ago, both my clutch lever and brake lever started squeaking on it's own. My hearing didn't suddenly improve.