Help replacing rear brake pedal

Hi,

I dropped my 2016 GRiSO at about 1km /hour and have bent the brake pedal.

I don't have a way of lifting the bike so I'm working at floor level and can't see too easily what needs to be dismantled to replace.

Amy guidance would be MUCH appreciated! I'm sure it'll be simple and obvious AFTER I know how it's do.


Cheers, Mark

Oh and an early heads up. Due to health issues I've decided that whilst I find riding " The Beast" an absolute blast that I'm going to sell and be content with riding my smaller and lighter V7. PM me if you might be interested . I'm in Melbourne Oz

After you have popped the clip (17) off the clevis (16) to disconnect the pushrod (14), remove the spring (23). The actual lever is fixed via a pin (24) that screws in from the back. A 5 or 6mm Allen key (I don't recall exactly) is required. Simply screw it out. The pin has two o-rings (25) on it to maintain the pin lubricant. Don't lose the washer (26).


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Thanks a lot Mark! That looks straightforward apart from the access at floor level and old bones.

One more question. Will I be able to pop 22 out of the "toe rest" with a screw driver or will I need circlip pliers?

That #22 E-clip doesn't look like its recessed so a pair of pliers should be able to push it out of the groove.
My pedal is slightly bent inward too so that job is on my to do list.

Yeah, wee screwdriver or pliers will get the e-clip off.

Thanks guys!

Sorry to resurrect an ancient thread but I've just changed over the pedal on mine. All went well except when I managed top knock the spring off. Can I find the top hole for it? No. Any help gratefully received.

edit-how it happened-low speed spill after I met a tractor coming towards me at speed the wrong way on the one way lane.

It seems that this thread provides an indirect answer to the question "Can the brake pedal bend and can it be bent back to perpendicular to the frame?"  Per my photo it seems to me that my pedal hasd been bent inwards and should in fact be perpendicular.  If so how can I do the bending?

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Remove, gentle heat and very careful persuasion. Too much persuasion and you will have two parts to the brake pedal - that simply won't work well and will require spending hard earned $.

Probably good to accept it a bit straighter rather than perfect. Also scour the suppliers to see if they have one and at what price (usually the number of first-born offspring).

Thanks, I've done some research on bending aluminum and it is complicated and not necessarily easy. So I'm unsure if I'm going to actually undertake this but if I'm feeling really lucky I might take a shot at it but probably not until summer.

Whatever you do don't try and un-bend it in-situ. The mounting will already be weakened by the knock that bent the lever and if you try and reef it the weedy little 6mm(?) threaded shank will snap. It may snap when you try to undo it to get the lever off.

Pete Roper wrote:

Whatever you do don't try and un-bend it in-situ. The mounting will already be weakened by the knock that bent the lever and if you try and reef it the weedy little 6mm(?) threaded shank will snap. It may snap when you try to undo it to get the lever off.

Agree completely!

Mine was bent like the one in the picture. I discovered it while on a trip far from home. After doing some research, I went to a local welding shop where we attempted to heat the pedal to about 600*F to soften the aluminum a wee bit. We got it too hot, discolored the paint, but it did straighten nicely.

My understanding is that you heat it up to about that temperature to rid the aluminum of the hardness it acquired as a result of bending during the impact. Called annealing. You let it cool down gradually (no quenching) and then you can bend it some.

Aluminium work hardens easily and as Gselvo says the bend is enough to work harden it so there is a risk of snapping if oyu bend it back.

Heating it for 5-10 mins is intended to remove that work hardening.
The temperature needed depends on the constituents of the alloy so its a guess

But with pure aluminium (sorry guys - UK spelling) it is the same temperature that soap blackens.

I have tried that succesfully on brake and clutch levers off other bikes ... good luck

Another easy indicator is to make some marks on the material with a Sharpie and heat until Sharpie marks disappear. Let it cool gradually before re-shaping. If you quench it it will become brittle and you'll be fucked. As mentioned, different alloys will have different annealing temps, but this will be close enough for what you're trying to do.

Street wrote:

Another easy indicator is to make some marks on the material with a Sharpie and heat until Sharpie marks disappear. Let it cool gradually before re-shaping. If you quench it it will become brittle and you'll be fucked. As mentioned, different alloys will have different annealing temps, but this will be close enough for what you're trying to do.

Right On - My exact thoughts and procedure.

Street wrote:

...........Let it cool gradually before re-shaping. If you quench it it will become brittle and you'll be fucked.

Oops thanks for mentioning that Street do not quench it

well that was almost the worst advice i have ever given........

I did it and it worked perfectly.  Took only about 5 to 10 minutes to heat up the brake pedal lever to 600 degrees Fahrenheit.  I had an IR thermometer and used that along with the Sharpie.  A little bit hard to see when the Sharpie color has dissipated enough.  Very easy to bend.  I did it gradually, annealing between efforts and checking against the in situ position.  Actually over bent it and had to go back.  Thanks to Beetle for the parts diagram and how to remove the lever.  Actually an easier way - just unscrew the lever holding bolt and pop off the spring.  Everything will then just drop out.  You can then easily remove the clevis clip and go to work.  One of my O rings stayed in the lever so be careful and remove it when heat annealing.  The spring was a little hard to get a handle on to remove but it went back on easily when reinstalling.  A very satisfying experience overall, maybe even fun.

I placed the lever between two pieces of wood in the vice when heating it, so the heat did not get dissipated through the vice and the lever would remain pretty. The first time around the wood did start to smoke at a bit over 600 degrees so that is another way to check the temperature. Also placed the lever between wood to bend it and used a small sledge with a piece of wood to tap it back to the right orientation.

We have an aluminium guru in our club, he does stunning work, his Imp engined Royal Enfield.
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He told me to rub the part with cheap hand soap then heat it until the soap turns black, I haven't tried this.

I do a lot of work with aluminium extrusions, flat bars etc. which will snap like a carrot if bent too sharp, it seems to have a grain that will make a saw wander off. The extrusion will become quite soft if heated with a propane torch.
Aluminium plate on the other hand is quite soft and easy to cut and bend.

Kiwi_Roy wrote:

...Aluminium plate on the other hand is quite soft and easy to cut and bend.

Again, depends on the alloy.

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gselvo wrote:

It seems that this thread provides an indirect answer to the question "Can the brake pedal bend and can it be bent back to perpendicular to the frame?"  Per my photo it seems to me that my pedal hasd been bent inwards and should in fact be perpendicular.  If so how can I do the bending?

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Here is the finished product - bent back

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I will also add the following experience. While a reformed lever may solve the problem, do not take the pivot "bolt" (part #24 in the diagram) for granted. The stress on that part during the tip over makes it very vulnerable to future failure. I had mine (shifter lever) snap half way to a camping destination. Fortunately, there was a local machine shop that kindly cobbled a fix for me and got me back on the road.

Better safe than sorry, just get a new one now and toss the stressed one in the bin.

I've been riding the bike with the bent liver for quite a while I think, maybe a couple of years. I don't think that the bolt holding it on is going to be a problem. Also to the extent that the lever was injured due to falling over or hitting something, the annealing process actually fixes that injury in the sense that it realigns the molecules in the aluminum the way they were supposed to be at the outset. I definitely will be watching for a broken rear brake lever though and hope it doesn't happen