I think I have a brake problem

Using the pedal only the brakes are so weak they hardly slow the bike at all. Will hardly hold stationary on a slight hill. On the main stand if apply the hand brake the rear wheel still turns freely. If I apply the pedal brake the rear does lock but on the road has very little effect. This is a relatively low k jap import 5th gen 98.

Any ideas would be appreciated.

Don

 

completely drain all of the old fluid, inspect your calipers and master cylinders for any visible leaks and inspect the brake pads. if there are no visual signs of any leakage and the pads are within spec, flush all of the lines with new fluid and bleed according to the manual. you should see an improvement.


.....

 

Ya got me on that one. lol

As mentioned above. Flush the brake systems and bleed it after the visual inspection. If there are any signs of leaks or hose seepage, you need to address that first.

 

I had the same problem on my '99 after bleeding the brakes with an airbleeder (Vac-U-La), had to rebleed by hand...think it has to do with the LBS. I agree with flushing and bleeding the system.

 

Just heading to the shed to remove rear caliper for a look see.

 

The front brake will not actuate the rear unless the bike is in motion. The actuation of the linked system to the rear is done by the rotational force exerted on the left front caliper. Now if you push on the right front caliper in the direction of wheel rotation, the rear brake should apply. Make sure the caliper slides and caliper pistons are not frozen up, The rear brake requires a moderate amount of force to achieve a notable amount of braking as the rotor is quite small. This is done in an attempt to eliminate rear wheel lockups caused by too much rear brake.

 

Brakes are important. Follow above advice, but educate yourself on how the brake system works. Proper maintenance, fluid, pads, etc all play an important role. It's not so bad once you learn, and gives you more satisfaction with your bike.

 

Ok thanks for all of the information and now I understand how the front influences the rear. When I took off the caliper I noted that the pistons were ok and functioned as expected. The pads look like brand new. I plan to see if I can wear them in a little and bleed the brakes with new fluid. Will be back when those tasks are complete.

Don

 

Brake fluid absorbs moisture and turns to crap after 3-4 years, so above recommendations to flush and refill should go a long way toward improvement.

With linked brakes you'll need to closely follow service manual instructions.

 

Have not bled system yet but will. The rear pads are like new ( bike is new to me). Have been dragging the rear brake a little and have noticed an improvement but still weak. If I jump on the pedal the bike slows but not with any authority or feel. Pedal is very hard.

Don

 

Hi Don,

If the pads are like new and you didn't install them it could have "el cheapo" hard compound pads installed, they are plentiful on eBay.... What I would do first is bleed the entire braking system manually by hand. You'll need to remove the rear wheel and pivot the rear caliper down to gain access to the bleed nipples. Check also the rear pistons move freely. Failing that I would be replacing the pads with a good quality set if you're still concerned. Also, when you press the foot brake hard whilst riding, you should feel the front also being applied( front end dips ).

Regards,
Navman

 

Don't expect dramatic stopping power from the rear brake, its not gonna stop like the front one does because it can't. Weight transfer during braking will cause the rear wheel to lockup long before you achieve serious deceleration like you get when you give the front brake a good squeeze.

 

Yes I am wondering about the rear pads. More work to do to solve this. Pistons work fine.

Cheers

 

If you're looking for a set of brake pads the general consensus is to get the EBC HH compound pads. I know I'll be picking them up when my OEM ones wear out. The OEM pads have pretty good bite but tend to be grabby at low temps when first starting out or riding in cold weather, making the front brake touchy when coming to a stop. I'm hoping the EBC's are a little more controllable.

 

So what I have done now is to take the front calipers off and grease the pins which were quite dry causing the front brakes to drag a bit. Wanted to clean them up a bit as well as part of the tidy up process. Have not tried things out since as has done nothing but bucket down. Going to do a full flush and bleed after Christmas. One other thing is the pedal height adjustment was all siezed up rusty. Freed that up. Pedal travel is still minimal and hard on contact. Will pull off the rear caliper soon.

Don

 

hmm, I am not sold on that thinking just yet. But they have been in business for some time.

 

I was going to ask what the recommended was - took the words outta my mouth. Cheers

 

Things are better after bleeding the rear brake through the front nipple. Some air came out. Also cleaned pads and caliper with brake kleen. Need to ride another VFR to compare performance. Do now get fork dive with a good stomp on the pedal and reasonable stopping performance