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1Back to top Go down   new front  brakes pulsing Empty new front brakes pulsing on Fri May 30, 2014 6:29 pm

audibob

audibob
Life time member
Life time member
I changed all my discs/ pads after suffering low speed pulsing. 
The original rear brake pulsed as well as the fronts.
 Not a happy bunny..... low speed pulsing is back again, although the new rear disc is good, so just the front .
The front wheel doesnt appear to be out, but I need to borrow  a dial gauge.
The front brake action is very grabby. Hopefully two caliper kits and fresh fluid will cure it. Will check the brake lever pivot arm. The pulsing is very annoying, its like one side is braking then the other. 
Is there anyway the ABS system could be "Pulsing ". The Red lamp goes out when i apply the brakes as it should. 
Any other ideas?
Bob


__________________________________________________
Yamaha 90
Honda CD 175
Honda CB 360 
Triumph T 140V Bonneville
Triumph T150 Trident
Honda CB750 F1
Cz 175
Yamaha XS 750
R 100/7
R 80
K100 LT
K100 LT current bike
    

2Back to top Go down   new front  brakes pulsing Empty Re: new front brakes pulsing on Fri May 30, 2014 7:45 pm

kartooo

kartooo
Silver member
Silver member
just tape a piece of plastic to the frt fork and have it touch the disc.
then rotate the wheel. should be obvious if you rotor is warped.
i use the handle of a cheap plastic kid's paintbrush.


__________________________________________________
85 k100rt current
04 vulcan 1500 classic sold
07 bonneville black sold
05 fjr1300 sold
04 r1150rt sold
91 k100lt sold
r80rt sold
85 K100 sold
    

3Back to top Go down   new front  brakes pulsing Empty new front brakes pulsing on Sat May 31, 2014 3:20 am

audibob

audibob
Life time member
Life time member
Hi Kartoo,
not sure of the chances of a new disc being warped, but I guess it can happen, they are floating discs which I had hoped would be better. I will set the wheel on stands and check disc runout and the wheel itself. I will also check the alignment of the forks too. I have a new set of non sintered ebc pads so will try them to see if the effect is reduced. The HH sintered pads are very grabby. Caliper seal kits have been ordered,will then check the master cylinder seals and hoses. Cannot expect to have no niggles on a 25 year bike, but seems a lot of people have experienced this and has taken a lot of time/ money to cure it.
Happy days.....


__________________________________________________
Yamaha 90
Honda CD 175
Honda CB 360 
Triumph T 140V Bonneville
Triumph T150 Trident
Honda CB750 F1
Cz 175
Yamaha XS 750
R 100/7
R 80
K100 LT
K100 LT current bike
    

4Back to top Go down   new front  brakes pulsing Empty Re: new front brakes pulsing on Sat May 31, 2014 5:58 am

xpc316e

xpc316e
Gold member
Gold member
I cannot imagine that this problem has anything to do with the ABS system.  If the problem cannot be solved, then it may be ameliorated by removing the bolts and rotating one disc with respect to the other and then retightening things.  That changes the phases of the pulsing of the two discs, and may help to cancel out the worst of it.


__________________________________________________
VIN 0191428, 1991 K100LT, formerly owned by Lancashire Constabulary. This old warhorse is now 'out to grass' and living in retirement in Suffolk, where it will be showered with appropriate love and care.

VIN 6459609, 1992 K1100LT, another ex-Police machine, even though she now looks like she is a former fire engine.
    

5Back to top Go down   new front  brakes pulsing Empty Re: new front brakes pulsing on Sat May 31, 2014 7:25 am

bushyintas

bushyintas
Silver member
Silver member
when you fitted the new disc was everything very clean where the disc bolts on, possibly not seated completely to wheel making the disc slightly out of true.


__________________________________________________
Bushy

k100 RT 1988 #0095723
K100 RT 1984 into Custom Single seat.  #0024503
    

6Back to top Go down   new front  brakes pulsing Empty New front brakes pulsing on Sat May 31, 2014 7:50 am

audibob

audibob
Life time member
Life time member
HI Guys thanks for both replies.
I guess the ABS being at fault was a long shot. Seems as though the fault has transferred to the new discs. I shall have the unit on the bench later so will check both discs and wheel for run out. I will try moving one disc around its hub fixing at a time to see if the effect is reduced, that is a good idea. Pen and paper at the ready.
Both sets of new sintered pads have a nice even contact on them . They are very grabby , not something I am used to. I do have an unused set of non sintered ebc pads, so may try them at some point.
I did make sure everything was clean prior to assembly, I may try and check for run out where  the disc sits the on the hub.The spindle seems to be ok. The front wheel bearings do have very slight movement, will change them too. The fork action is very harsh, as if there is too much fluid in there. Will drain out measure quantities, and refill with correct amount.
Better get on with the rear caliper overhaul before I move onto the fronts. Happy days
Bob


__________________________________________________
Yamaha 90
Honda CD 175
Honda CB 360 
Triumph T 140V Bonneville
Triumph T150 Trident
Honda CB750 F1
Cz 175
Yamaha XS 750
R 100/7
R 80
K100 LT
K100 LT current bike
    

7Back to top Go down   new front  brakes pulsing Empty caliper bolt setting on Sat May 31, 2014 10:24 am

audibob

audibob
Life time member
Life time member
Anyone know the torque setting for the caliper body to body  bolts before i bolt her up, and why only one seal in the repair kit?


__________________________________________________
Yamaha 90
Honda CD 175
Honda CB 360 
Triumph T 140V Bonneville
Triumph T150 Trident
Honda CB750 F1
Cz 175
Yamaha XS 750
R 100/7
R 80
K100 LT
K100 LT current bike
    

8Back to top Go down   new front  brakes pulsing Empty Re: new front brakes pulsing on Sat May 31, 2014 11:05 am

Inge K.

Inge K.
VIP
VIP
@audibob wrote:Anyone know the torque setting for the caliper body to body  bolts

30 Nm +/- 5 Nm.

Only 1 seal?.......it should be 2 of each of the 3 different seals in the set.


__________________________________________________
Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

9Back to top Go down   new front  brakes pulsing Empty New front brakes pulsing on Sat May 31, 2014 2:04 pm

audibob

audibob
Life time member
Life time member
Thanks Inge, 
I think I read someone else commented on only getting one "O" ring.  He found the correct type and size so will find the thread and order  some spares .


__________________________________________________
Yamaha 90
Honda CD 175
Honda CB 360 
Triumph T 140V Bonneville
Triumph T150 Trident
Honda CB750 F1
Cz 175
Yamaha XS 750
R 100/7
R 80
K100 LT
K100 LT current bike
    

10Back to top Go down   new front  brakes pulsing Empty Re: new front brakes pulsing on Sat May 31, 2014 2:07 pm

Inge K.

Inge K.
VIP
VIP
O-ring : 6,6 x 1,8 mm


__________________________________________________
Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

11Back to top Go down   new front  brakes pulsing Empty new front brakes pulsing on Sun Jun 01, 2014 3:35 am

audibob

audibob
Life time member
Life time member
Thanks Inge,
I will phone moterwerks uk and ask why the repair kit contained only one 0 ring.


__________________________________________________
Yamaha 90
Honda CD 175
Honda CB 360 
Triumph T 140V Bonneville
Triumph T150 Trident
Honda CB750 F1
Cz 175
Yamaha XS 750
R 100/7
R 80
K100 LT
K100 LT current bike
    

12Back to top Go down   new front  brakes pulsing Empty new front brakes pusling on Sun Jun 01, 2014 4:48 pm

audibob

audibob
Life time member
Life time member
Busy day.
Rotated discs around the hub, but pulsing constant.
 Fork oils drained ( 330ml) and refilled with 300ml which has made the front end nicer. Upper and lower leg bolts replaced, someone must have used an english set on this bike..just had enough grip to remove them. 
Front brake fluid changed. Inspected both front calipers for piston movement, and found someone had tried to get one out with a pair of molegrips, the face that pushes the pad was really chewed up, why would anyone do this??. I wonder whether the chewed piston may be pushing the pad out of line slightly,  to create the pulsing. I need to remove it and see if the face is still flat.
 Most of the seals were a yellow colour, would these be original or just age related
 I will probably end up replacing the front pistons and seals . 
I have fitted a new set of non sintered ebc pads for the time being. 
Next weekend will be a more in depth look at the wheel, and see if the disc seat hubs are true, and the new discs of course.
Good fun....


__________________________________________________
Yamaha 90
Honda CD 175
Honda CB 360 
Triumph T 140V Bonneville
Triumph T150 Trident
Honda CB750 F1
Cz 175
Yamaha XS 750
R 100/7
R 80
K100 LT
K100 LT current bike
    

13Back to top Go down   new front  brakes pulsing Empty Re: new front brakes pulsing on Sun Jun 01, 2014 5:04 pm

sidecar paul

sidecar paul
Life time member
Life time member
The 'yellow' dust seals sound like the (better) silicon seals. The black ones are not so heat resistant.

Paul.


__________________________________________________
'84 K100RS (0014643) (owned since '85), 86 K100RS (0018891) with Martello sidecar (built as an outfit in '88),
'51 Vincent (since '67),'72 Montesa Cota (from new), '87 Honda RS125R NF4 (bought 2015) 
....No CARS never ever!
    

14Back to top Go down   new front  brakes pulsing Empty new front brakes pusling on Sun Jun 01, 2014 5:36 pm

audibob

audibob
Life time member
Life time member
Thanks Paul, I was beginning to wonder how old my bike really is....


__________________________________________________
Yamaha 90
Honda CD 175
Honda CB 360 
Triumph T 140V Bonneville
Triumph T150 Trident
Honda CB750 F1
Cz 175
Yamaha XS 750
R 100/7
R 80
K100 LT
K100 LT current bike
    

15Back to top Go down   new front  brakes pulsing Empty new front brakes pulsing on Tue Jun 03, 2014 2:42 pm

audibob

audibob
Life time member
Life time member
After fitting the non sintered pads,  there is feel to the front brakes again, too early to say but doesnt seem be any pulsing. I intend to remove the front pistons, fit new seals, and  replace the damaged piston with the  good one from my rear caliper, which will have two new ones. If the front hoses are original, and they probably are, then as everyone suggests that they might be collapsing, will change those too. 
Will  check the wheel for straightness too , not quite like painting the Forth road bridge......but seems never ending at the moment, all part of the fun I keep telling myself, cant wait the change the head bearings...
infamy infamy its got it in for me...


__________________________________________________
Yamaha 90
Honda CD 175
Honda CB 360 
Triumph T 140V Bonneville
Triumph T150 Trident
Honda CB750 F1
Cz 175
Yamaha XS 750
R 100/7
R 80
K100 LT
K100 LT current bike
    

16Back to top Go down   new front  brakes pulsing Empty Re: new front brakes pulsing on Tue Jun 03, 2014 2:58 pm

mike d

avatar
Life time member
Life time member
I keep telling myself, cant wait the change the head bearings...
infamy infamy its got it in for me...

If you are also a full member of the BMW Club (UK), then they have a Tool Hire service. It includes a suitable slide hammer extractor for the bearing cups, so the job is easy.

Mike

    

17Back to top Go down   new front  brakes pulsing Empty new front brakes pulsing on Tue Jun 03, 2014 5:19 pm

audibob

audibob
Life time member
Life time member
HI Mike,
 thanks for that info, anything to make the job easier.
Bob


__________________________________________________
Yamaha 90
Honda CD 175
Honda CB 360 
Triumph T 140V Bonneville
Triumph T150 Trident
Honda CB750 F1
Cz 175
Yamaha XS 750
R 100/7
R 80
K100 LT
K100 LT current bike
    

18Back to top Go down   new front  brakes pulsing Empty New front brakes pulsing on Fri Jun 20, 2014 5:27 pm

audibob

audibob
Life time member
Life time member
Stripped both front Calipers, cleaned , red rubber grease on  seals and  pistons etc, refitted and bled. I decide to refit the HH sintered pads again .  Checked both calipers for actuation and retraction when I released the brake lever, and found all pistons acting  together.
The brake action is now much smoother, very positive due to using the HH pads again, with only a slight hint of any pulsing.  Must have done something right!!
There is slight play at the brake lever before actuation, but this may be normal. I can certainly get her nose diving just using two fingers on the lever...So for the time being I am happy. 
I will check the wheel itself at some point.
Now where was I with the list "to do"
Bob


__________________________________________________
Yamaha 90
Honda CD 175
Honda CB 360 
Triumph T 140V Bonneville
Triumph T150 Trident
Honda CB750 F1
Cz 175
Yamaha XS 750
R 100/7
R 80
K100 LT
K100 LT current bike
    

19Back to top Go down   new front  brakes pulsing Empty Re: new front brakes pulsing on Fri Jun 20, 2014 5:46 pm

billtr96sn

billtr96sn
Silver member
Silver member
As a side point, sintered pads are known for giving less 'feel' but better braking


__________________________________________________
Something witty is supposed to go here... help!! new front  brakes pulsing Uk-log10
http://www.billsbikechat.co.uk
    

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