Author Topic: rear brake pedal travel  (Read 9975 times)

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Offline stump magnet

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rear brake pedal travel
« on: August 06, 2012, 06:08:45 am »
hi all, i would like to reduce the travel of the rear brake pedal so that i dont have to press it down so far to get the same braking effort, the reason i ask is i have to run the rear brake quite tight on the adjuster to get the short travel on the pedal i like and so it heats up and starts to bind (so i have to run it slack for me) but if i had more slack in the adjustment but still a short pedal travel then the brake would not bind so my question is what do i have to do to the pedal or the brake arm? do i lengthen or shorten the pedals pivot or the arms? i have a longer curved rear brake arm at my disposal but have not tried it, it must all be a question of leverage ratio's i supose? the bike is a 360 sidepipe, cheers

Offline shortshifter

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Re: rear brake pedal travel
« Reply #1 on: August 06, 2012, 11:16:05 am »
Stumpy,I dont like a lot of travel either but you dont want the pads binding.On one of my bikes the brake rod goes through the ferrel (I think that's how you say it) then I have a couple of spacers probably about a cm  or 2 long then the threaded nut,seems to work pretty well.On the other newer bike I have the usual arrangement,but have put a spring from the countershaft sprocket guard (homemade) to a hole in the brake pedal which keeps it up under your boot and gives a bit more progressive feel to the brake.Your brake actuator arm position can also be altered on the splined shaft which might help.All a bit fiddly,you gotta these old bikes :D

Offline VMX60

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Re: rear brake pedal travel
« Reply #2 on: August 06, 2012, 12:03:31 pm »
Stump

What I run on all the CZ is a Go Kart pedal spring from the rear brake pivot arm back to the rear chain adj bolt gives you tension on the pedal and free play on the brake shoes no matter how much play up or down you like

Back in the day most CZ guys used old inner tube to do the same job

My ankle does not pivot either   ;D

Cheers

Offline stump magnet

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Re: rear brake pedal travel
« Reply #3 on: August 06, 2012, 05:14:52 pm »
Thanks for the replys guys but the return of the pedal is not an issue, the issue is how can I get more movement out of the rear ar arm for the same or less movement of the pedal

Offline VMX60

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Re: rear brake pedal travel
« Reply #4 on: August 06, 2012, 07:50:13 pm »
Stump

Does the brake have good stopping power can you lock the rear wheel without stomping on the  pedal

Try the longer rear arm set to the rear of vertical on the brake plate arm

The std CZ  brake is one of the best

Had a problem when I had the rear shoes rebonded with wrong type of lining ,Same as you , Rear after one lap red hot binding with no stopping at all pull the rear wheel after each race to rough the shoes up lasted about one lap stuffed around with pedal and rear arm angles nothing work untill the shoes were rebonded with correct lining now works with mild pedal pressure as my ankle only has 10% pivot so the shoes are just about touching the drum   :-\

Cheers

Offline stump magnet

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Re: rear brake pedal travel
« Reply #5 on: August 06, 2012, 09:36:54 pm »
have played around with CAD (cardboard aided design ;D) and a longer pivot on the pedal would result in more movement of the brake arm, a longer brake arm requires more pedal movement, the shoes are standard CZ by the way and has great stopping power, i just like a light switch style brake pedal
« Last Edit: August 06, 2012, 09:39:48 pm by stump magnet »

Offline shortshifter

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Re: rear brake pedal travel
« Reply #6 on: August 07, 2012, 08:05:57 am »
There is also a fair bit of flex in the brake rod which has to take up before they bite,so maybe a more rigid brake rod???have seen one with 90 degree bends rather than the curved bend to get around the shock.

Offline tony27

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Re: rear brake pedal travel
« Reply #7 on: August 07, 2012, 06:55:59 pm »
Possibly try running the rear lever pointing downwards with a straight brake rod, that's the set up I use although with an extended rear lever.
Also using a billet brake plate which takes out the flexing from the standard one

Offline stump magnet

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Re: rear brake pedal travel
« Reply #8 on: August 08, 2012, 04:02:10 pm »
Ok have sorted it, have made a billet back plate and new billet lever with the rod hole 20mm further up how do I post pics from smart phone?

Offline tony27

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Re: rear brake pedal travel
« Reply #9 on: August 08, 2012, 05:07:00 pm »
You'll need to use a hosting site like photobucket or flicker.
http://ozvmx.com/community/index.php?topic=17785.0

Offline 09.0

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Re: rear brake pedal travel
« Reply #10 on: August 08, 2012, 05:37:55 pm »
You can send via iPhone to photobucket, obviously you have to have an account ( free ) and photobucket tells you how to do it.

Offline GMC

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Re: rear brake pedal travel
« Reply #11 on: August 08, 2012, 08:42:32 pm »
Possibly try running the rear lever pointing downwards with a straight brake rod, that's the set up I use although with an extended rear lever.

The brake rod should run parallel to the swingarm, either above or below
If the brake rod runs diagonally across the swingarm it will cause the brake pedal to move with suspension movement
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Offline stump magnet

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Re: rear brake pedal travel
« Reply #12 on: August 08, 2012, 09:12:37 pm »
does this work?

Offline Suzukal

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Re: rear brake pedal travel
« Reply #13 on: August 08, 2012, 09:40:47 pm »
can't see any picture???

You can run your brake rod, parallel, above, below the swing-arm or anywhere you like, as long as where the brake rod meets the brake lever is where the swing-arm pivot bolt is.    Right in the center of the bolt.
If it’s not, then the suspension movement will stuff it up. ( eg: if it pivots below the swing-arm, you land of a jump and it locks up the back wheel ).

If you want to get less movement at your brake lever, you need a shorter rear brake lever on the back hub.

Offline stump magnet

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Re: rear brake pedal travel
« Reply #14 on: August 09, 2012, 05:17:08 am »
has this worked?