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Main Area => General GS500 Discussion => Topic started by: conoral11 on January 30, 2010, 07:40:45 AM

Title: Rear brake pedal wobble - Is it normal
Post by: conoral11 on January 30, 2010, 07:40:45 AM
Hey there,

I've been riding my bike for a while now, and have done numerous things to it. Shes in good working order (Although i've just had to buy a new battery, my last one sulphated itself!)

I'm a bit curious to how the rear brake pedal should feel. My rear brake works fine but when you press the pedal downwards, theres alof of side to side play with it.

On my Dads Honda there is no side wobble at all, but theres quite a bit on the GS.

I've tried placing washers inbetween the pedal and rearset, with not much luck (A rubber one worked and solved it, but then the pedal just got stuck hehe).

Can anyone confirm if the side to side wobble is a common thing on the GS?

Many thanks

Conoral11
Title: Re: Rear brake pedal wobble - Is it normal
Post by: scottpA_GS on January 30, 2010, 08:19:14 AM

No, not normal at all..

is your rotor bent maybe? and the fluid pulsing back is creating the movement?
Title: Re: Rear brake pedal wobble - Is it normal
Post by: conoral11 on January 30, 2010, 09:36:14 AM
It does it even when on the center stand, so I doubt it is the rotor, plus I get no pulsing when braking. Before I rebuilt my caliper I had my rotor checked for flatness and it came back clean.

Does that mean my rearset and pedal have worn badly?

Conoral11
Title: Re: Rear brake pedal wobble - Is it normal
Post by: BaltimoreGS on January 30, 2010, 09:52:36 AM
My old GS has about 2-3mm of play side to side when I push at the tip.  If you have a lot of play the shaft is probably worn out.  Warped rotors would cause a pulse in the pedal when braking, no effect on lever action when stopped.

-Jessie
Title: Re: Rear brake pedal wobble - Is it normal
Post by: dauphinc on January 30, 2010, 10:01:18 AM
Double check that everything is secure holding it in. Take off the heel guard (3 Allen heads) and go from there. A good mechanic is also a good investigator.  :thumb:
Title: Re: Rear brake pedal wobble - Is it normal
Post by: conoral11 on January 30, 2010, 10:08:32 AM
Thanks for all the info guys, its really helping!

I've checked, re checked, took it off thinking I was doing something wrong checked. I think the idea that my spindle on the pedal might be worn is a good one. Does anyone have the inside measurment of the slot and the measurment of the pedals diameter?

I remeber, having everything disconnected and just the pedal placed in the rearset that it "wobbled" and thought to myself, if only I could make a shim that would sort it.

Just need to work out whats worn before I start replacing things

Conoral11
Title: Re: Rear brake pedal wobble - Is it normal
Post by: bobthebiker on January 30, 2010, 12:58:27 PM
my first thought is that a sleeve inside the pedal going on the shaft would probably do the trick, but you'd still need to know which part is worn first.   
Title: Re: Rear brake pedal wobble - Is it normal
Post by: conoral11 on January 30, 2010, 01:13:26 PM
I'll borrow a caliper from uni next week and measure both parts.

What would be a suitable material to make a sleve from, since I can't see the gap myself?
Title: Re: Rear brake pedal wobble - Is it normal
Post by: jeremy_nash on January 30, 2010, 02:02:02 PM
I woud just get one from someone parting out a bike on here, just seems better to replace a brake component, then TRY to shim it
Title: Re: Rear brake pedal wobble - Is it normal
Post by: conoral11 on January 30, 2010, 02:08:22 PM
That was my origonal intent, but without knowing what is out of spec I could buy the whole hog and get reset + lever, or I could find out whats up and get just the lever or reset for example.
Title: Re: Rear brake pedal wobble - Is it normal
Post by: jeremy_nash on January 30, 2010, 02:12:08 PM
oh, ok I see then, I'll go check mine out
Title: Re: Rear brake pedal wobble - Is it normal
Post by: jeremy_nash on January 30, 2010, 02:14:03 PM
less than 3mm play in mine
Title: Re: Rear brake pedal wobble - Is it normal
Post by: conoral11 on January 30, 2010, 02:15:07 PM
Do you notice it when you operate it  with your foot?

I notice it quite badly when I do
Title: Re: Rear brake pedal wobble - Is it normal
Post by: jeremy_nash on January 30, 2010, 02:22:26 PM
no, I never knew, have ridden it barefooted, with sandals, sneakers, hiking boots, and even proper riding boots, never knew I even had any play in it at all.

how far back and forth does yours move?
Title: Re: Rear brake pedal wobble - Is it normal
Post by: conoral11 on January 30, 2010, 03:20:12 PM
Theres no backwards forwards movement in the pedal, just side to side, haven't got access to the bike right now (its stored at a frriends garage).

I'll get to it during the week when he's back and take a measurement. Its enough to make the brake feel strange, and notice it when moving it by hand.
Title: Re: Rear brake pedal wobble - Is it normal
Post by: conoral11 on January 31, 2010, 10:47:14 AM
I've manged to get hold of a whole rearset assembly with master cylinder for very cheap, should arrive within the week. Hopefully i'll be able to measure them all and work out where the wear has occured!

I'll keep you guys informed, thanks for all the info so far.

Conoral11
Title: Re: Rear brake pedal wobble - Is it normal
Post by: sledge on January 31, 2010, 01:36:10 PM
The rear brake pedal assembly is a triumph of manufacturing cost V function. They are not what anyone could call quality piece of engineering built to high tolerances. Assuming the return spring on the rear hasnt gone AWOL allowing the whole thing to slop around the wear will be on the pedal pivot or the bush that supports it...or both, neither of which could be called substantial. Or..... there might not be any wear at all and you might just have a pedal with a pivot diameter that is at min manufacturing tolerance together with a bush of a diameter that is at max tolerance. Upshot being they fit together like a d*** in a shirt-sleeve.

Find a good used one with less play than yours, clean the pivot off and pack it with waterproof grease then fit and forget. Its the cheapest and easiest solution.