Front Calipers - How to retract more ?

Hello everyone,

I recently replaced front pads and had the rear done about 2000Kms ago. What I noticed is that the front calipers do not retract all way so the wheel spins freely.

When I turn the wheel by hand with moderate force the wheel turns around one time and then stops.

If I can some how get the calipers to retract more then there will be a significant increase in less fuel consumption.

I have bled all the lines and even did the trick of opening the reservoirs, push the pads back, close the reservoirs and then only start to pump the levers so that it forms a vacuum but it still no joy ! :frown:

Ive had the bike now for 8 months and had done 8000Kms (24000 total).

Its a non abs model and I get around 320Km/tank.

My questions are :

1. Is this normal ?
2. How many rotations does your front wheel make before stopping when using moderate force ?
3. The back seems totally free compared to the front, is this normal ?
4. What can be done to get the calipers to retract more ?

Any help will be highly appreciated !

Cheers
Mario

 

Sounds like there is definitely too much force on the front wheel.

Did you clean the caliper pistons before pushing them back in?

 

Elwray, no I did not. I did not feel that I needed to because they look like new.

There are no dirt there and every time I took the calipers off to inspect all works and looks well....

 

As long as they aren't getting stuck out then that shouldn't be the problem...

I'm sure someone will be along shortly with some more knowledge... sorry couldn't be of more help.

What kind of pads did you put in there?
What year is the bike?

 

Not a problem mate,

She's a 04 and the pads are Ferodo...

I think everyone is still on hols !

 

I think you're right... my office was pretty empty last week, and there aren't too many more people here today.

I just did front and back pads on my 2003 Non-ABS with EBCs. The only thing I really noticed was that the front brake lever had much less travel with new pads than the [very] old ones.

When you bled the lines, did you follow through all of them? I believe it was 1 on the right front to the front cyl, 1 on the front left to the front cyl, and a second on the front left to the rear cyl. Then also the proportional valve and the rear valve on the rear caliper to the rear cyl.

Though if there was air in the lines you'd probably have the opposite issue that you're having now...

 

Ye ! I bled all the lines which was faultless anyway...

1. Front calipers
2. Rear caliper
3. Midway valve under the seat
4. Boost cylinder on left front caliper
5. Second nipple on left front caliper

It seemed to make the wheel spin more freely but after one ride its back to square one !

Yeah, if there was air in the system then it will only happen after a ride or when the brakes are hot, but my problem occurs even when the bike is cold and not been ridden. This is the fist time I come across this type of problem and I work on bikes everyday of my life !

 

Following inspections points I found on the Dutch VFR owners club forum are:

- Using the correct torque value of the wheel axle.
- Cleaning the guiding pins LEFT_FRONT_BRAKE_CALIPER nr 11 on the fiche.
- Inside the caliper you might find some mixture of old brake fluid which can be thick. Overhauling the caliper, replacing the seals and polishing the pistons can help.

Check chapter 15 for hydraulic brake or chapter 16 for ABS of the service manual which is available through the link I posted in your starter valve question.

Arno

 

kinda sounds like the pistons in the calipers did not retract at the same level when you installed the brakes.
no if you go for a ride and put bike on the center stand without using alot of brakes for the final stop, does it spin free?
also there is a line on the axle that you need to be able to see when you tighten axle bolt or it will cause drag on the rotors, looking head on at the bike it will be on the right side.
make sure you can see the line before and after to tighten up the axle.

 

Thanks for the replies Arno(again) and vfr rider !

I have checked the no11 pins on the caliper and yes they can be at fault if they are dirty but they are not!

Also don't think that the calipers need overhauling but what I haven't checked is the axle...maybe it is in too far, will go and have a look tomorrow and report my findings !

Cheers

 

Right,

Had a look today, axle was a bit more in than the norm but did not change anything.

So I too the calipers off again, made the plungers come out and cleaned everything with carb cleaner just to make sure there isnt anything stuck between the plungers and walls.

No change !

I havnt ridden the bike yet since its stripped for a good clean, as soon as I do I will let you guys know.

Any other suggestions ?

Thanks
Mario

 

Do you have the wheel spacers in correctly? Is the pressure relief hole inside the master cylinder resevoir clean?

 

You might have a warped rotor....does it always catch in the same spot ??

ever notice a pulsation in the brake lever ??

 

I just finished the brakes on my VFR, New pads, New fluid,cleaned etc.... I have the same results. The back does turn better than the front and I get about one turn on the front. I will ride it in the spring and hopefully they will just wear ..

 

Spacers are in correct, if they wernt then one of the rotors would catch on the fork leg.

Took the master cylinder off, stripped it and cleaned it - no dirt.

Not a warped rotor, no pulsation on lever, always catching.

It seems to already chow the inner left side pad more than the others but it is definitely both calipers at fault as I have tested it both ways.

Can someone please spin their wheel and count the rotations ? Maybe its all normal but in my books a wheel shouldn't turn so tight !

 

could be a dirty bore or mild corrosion. I just spent $700 unexpectedly on my Toyota Landcruiser last week for this very situation (new pads & rotor) due to the bore becoming corroded and the piston not retracting... something like this may help:

KD Tools - Brake Cylinder Hones, Stones, and Flex-Hones

use with extreme caution as less is more - you dont want to change the tolerance of the bore, just clean it up

 

Uh, not to be a douche here as this seems to be a brake related issue, but, have you checked the wheel bearings/spun the wheel with NO calipers installed to see if it still drags?????

 

Wheel spins fine with no drag calipers removed ! :smile:

 

One last bit...........There is an article in this months cycle world magazine describing similiar issues and they make reference to a bleed hole in the reservoir that allows transfer of fluid to go back, if this is clogged the fluid will not go back.
Page 67 article ( no hands braking) CYCLE WORLD