[pbergie]

New Member, I ride a 97' 1500 Aspencade. LOVE IT. I bought it as a fixer-upper, and have gone through the gammit of trials and tribulations, all the while learning quite abit about my 'cherry girl.'
HOWEVER, I've stumbled upon a real toughy....
Symptoms: will get on bike at times, and rear brake works just like it is supposed to, lots of back-pressure on pedal, and all is good.
THEN, sometimes I will get on the bike, or even riding it, and the rear brake controll will just just drop out!, like NO brake pressure. I usually end up pumping the hell out of it, and limp it home, but have found NO leaks, full resevoir, no perceptable issues whatsoever.
ANY help would be greatly appreciated, I would REALLY like to avoid the dealer if possible.
Thanking you all in advance,
Paul:wtf:

 

[John J]

Have you bled new fluid through it yet? You probably already have and already know that the rear brake controls the front left too. As you say you can pump it back into life it does suggest air in the system.

 

[satan]

This scenario is not too uncommon where contamination (or indeed excessively low fluid level or air infiltration into the fluid level) may exist in the master cyinder.

If you're not certain of the maintenance on the bike - a FULL flush of the coupled braking system with fresh/new DOT4 fluid would be a first step, and if the issue epersists, then look at rebuilding the rear mastercylinder.

 

[fgh]

IMHO that's most likely a master cylinder problem. I would rebuild it.

 

[Wingsconsin]

IMHO that's most likely a master cylinder problem. I would rebuild it.

Try the COMPLETE flush first ..Brake fluid is cheap...

THEN - the master cylinder rebuild if there is no improvement..

Flushing sometimes does not clean out all the sludge from the caliper either...if you have to do the MC then consider doing the Calipers as well...the only then left then would be brake lines...stainless steel braided would make it the trifecta and your brake would work better than new...

 

[glhonda]

Bad axle bearings could also be the culprit (not likely, just something to check) Too much run out in the rotor/wheel can push the pistons back enough to cause a "double or triple" pump to get a firm pedal.

 

[redwing52]

What can happen is that when the piston seal gets old and looses it's resilience it does not always seal. The hydraulic force on a GOOD seal will force it to expand and seal as it should. With a hard worn seal the fluid just goes right by and returns to the reservoir. That's why you see no leaks. The fluid just retrurns back to the reservoir. Is it more likely on cooler days as the cold will make the seal even less resilient and aggravate the issue. A flush might fix it but it is brakes maybe a better solution is the rebuild. Not that hard or expensive.

 

[ALEX BERECZKY]

Bleed the brakes (rear and front left), and also hang a weight (ex: 1 gallon paint can) on the foot pedal overnight, to assist in bleeding the line.

 

[pbergie]

Thank You all for the suggestions and advice. It is appreciated.
I think I will start with the obvious, work up from there. I'll try anything short of spending a fortune at the dealership. I would rather spend the money riding!
See you on the road.....

 

[Wingsconsin]

DO it yourself and SAVE $$

Thank You all for the suggestions and advice. It is appreciated.
I think I will start with the obvious, work up from there. I'll try anything short of spending a fortune at the dealership. I would rather spend the money riding!
See you on the road.....

Each rebuild kit is about $35 ..
One Front caliper - One Rear caliper - One master cylinder = $105.00 & Brake fluid is cheap...
Your time is FREE - It is really easy as long as you don't hurry and do it efficeintly - the dealer (stealer) would be a lot more $$.
While you are in there check & replace if needed brake pads..about $25 each set..? Another $50..For les than $200 it will be nearly perect again...If you don;t know how there are tutorials online here that can help or maybe someone near you could come over...Or bring it to my house near Milwaukee and I will teach you..I have all the required tools...

 

[dizzy]

It's not unusual for 1500 to get a spongy brake pedal during storage. I always find the air at the left front caliper. Usually doesn't come and go like your description. A quick bleed and they're good to go.

Could be a loose fitting, or a bad brake hose. Some of the brake plumbing is hard to see. Sometimes brake fluid weepage might not be obvious without looking really close and some observation of brake fluid loss over time. Some good suggestions posted above. Best be getting it fixed...takes a long time to pull down from highway speed with just the lever.

 

[Ken Bergen]

As it happens when in motion I'd be looking for disc run-out.

Humm, isn't that what glhonda said earlier?:?

 

[glhonda]

As it happens when in motion I'd be looking for disc run-out. Humm, isn't that what glhonda said earlier?:?

Don't listen to that gl guy. I know him personally and he's a JERK!!

 

[Ken Bergen]

Don't listen to that gl guy. I know him personally and he's a JERK!!

Being a JERK doesn't mean he's wrong as even a JERK can be right occasionally. :raspberry::ROFL:

 

[glhonda]

Back on topic.

 

[96aspencade]

Just another reminder to bleed the L front "before" your rear caliper. :waving:

 

[wilmo]

My 1200 did that as well before I rebuilt the calipers. Didn't rebuild the master cylinder. Brakes are fine now. The pistons would bind up due to the corrosion behind the o rings. It eventually locked up forcing me to fix them. If you haven't, I would recommend rebuilding the calipers, cleaning the corrosion goes a long way.

 

[Original Wingnit]

New Member, I ride a 97' 1500 Aspencade. LOVE IT. I bought it as a fixer-upper, and have gone through the gammit of trials and tribulations, all the while learning quite abit about my 'cherry girl.'
HOWEVER, I've stumbled upon a real toughy....
Symptoms: will get on bike at times, and rear brake works just like it is supposed to, lots of back-pressure on pedal, and all is good.
THEN, sometimes I will get on the bike, or even riding it, and the rear brake controll will just just drop out!, like NO brake pressure. I usually end up pumping the hell out of it, and limp it home, but have found NO leaks, full resevoir, no perceptable issues whatsoever.
ANY help would be greatly appreciated, I would REALLY like to avoid the dealer if possible.
Thanking you all in advance,
Paul:wtf:

As a wing owner for more years than I care to count, this is a typical complaint generally seen after a 1500 wing sits for a period of time.

It is rare that the rear master cylinder goes bad on a 1500...unless it has had no maintenace through its life time.

Check the rear master fluid level.
Remove the left front rotor cover.
Pump the brake pedal 5 times.
While holding the pedal down, loosen the brake line banjo fitting (not the bleeder valve).
Tighten the banjo fitting and release the pedal.
Repeat the above process 2 more times.
Check the brake fluid level and add as necessary.

Remove the left rear saddle bag.
Pump the brake pedal 5 times
While holding the pedal down, loosen the brake line banjo fitting (not the bleeder valve).
Tighten the banjo fitting and release the pedal.
Repeat the above process 2 more times.

This will get most of the air out of the system.

Now bleed the front left caliper using the same technique as listed above, but bleed it using the bleeder valve.

Once there is no air in the front, move to the rear caliper and repeat the above process using the bleeder valve.

This is a 2 person process doing it this way, but it works well. The reason I say to do the initial bleeding through the brake line banjo fittings is that it is much faster at removing air in the system.


Good luck with the fix.