Front brakes vs Rear Brakes

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mm58
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Front brakes vs Rear Brakes

Post by mm58 »

I just adjusted the brakes on my 710K last weekend.

When I had all the drums off and was inspecting, I saw that the front wheel brake parts were very well covered
with black brake dust and a small amount of loose dust in the drums (as I would expect)

On the other hand, the rear brakes were almost completely void of any brake dust residue
anywhere.

So my question is: Is this normal? Seems like my rear brakes weren't contributing much
to the braking effort. (my assumption because of the lack of any significant brake dust)

What should the ratio of braking work be between the front and rear? 50/50? More front? More rear?

Any education appreciated...

Mike

p.s. They are currently set at: REAR- back off 4 clicks; FRONT- back off three clicks
Mike

'76 710K
undysworld
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Re: Front brakes vs Rear Brakes

Post by undysworld »

Always, way more braking is done by the front brakes than is done by the rears. Just look at the relative sizes of front to rear brakes on most vehicles. Fronts are typically bigger. Even the Pinz has double pistons on the front and only singles on the rears. The situation gets even more lopsided as the weight of the vehicle transfers forward during braking.

I'd adjust those brakes just a bit tighter. Back off 2 on fronts and 3 on rears, IIRC.
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TechMOGogy
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Re: Front brakes vs Rear Brakes

Post by TechMOGogy »

Not sure what 'a little' is but perhaps like undysworld suggested - reduce the amount your backing them off
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Jimm391730
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Re: Front brakes vs Rear Brakes

Post by Jimm391730 »

How far you back off the adjusters after you feel drag on the drum will affect the pedal drop before you get braking force; back off more, the pedal gets closer to the floor before the brakes take effect (to the point where you need to pump the pedal to stop).

However (with a minor exception in a 712 ) you should back off all wheels and axles evenly so all brakes start to work at the same time. If you intentionally unbalance the back off (more on the rear, as you described) the rears won't be doing anything under gentle braking - this may be why you don't see much residue in those drums.

IMHO braking effectiveness is the most crucial aspect of any vehicle. Adjust the brakes correctly (evenly) and be safer.
Jim M.
712W and 710M
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totaljoint
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Re: Front brakes vs Rear Brakes

Post by totaljoint »

(with a minor exception in a 712 )
As a 712 owner.. whats this minor exception you speak of?
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Andre
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Re: Front brakes vs Rear Brakes

Post by Andre »

Center and rear axles get adjusted differently to maintain traction on both axles when hard braking. Don't remember off hand which is adjusted harder than the other without the manual.(I service mostly 710's)
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TechMOGogy
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Re: Front brakes vs Rear Brakes

Post by TechMOGogy »

totaljoint wrote:
(with a minor exception in a 712 )
As a 712 owner.. whats this minor exception you speak of?
in the operators manual pg 158:
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edzz
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Re: Front brakes vs Rear Brakes

Post by edzz »

The dual leading brakes on the front are designed to provide maximum braking power when traveling forward and don’t work as well in reverse.
The rear brakes have one shoe leading and one trailing; the rear brakes provide the same power going forward or backwards.
The rear brakes contribute a relatively small amount of braking force when going forward, if they exerted as much braking force going forward as the front brakes you would constantly be locking up the rear wheels and creating handling problems.
When breaking hard the rear end can get very light due to the weight being transferred to the front wheels.
A good example of this is seen watching road racing motorcycles under hard braking; it is not uncommon to observe the rear wheel to be totally off the ground.
If the rear tire has limited or no contact with the ground better brakes don’t do anything for you.
And yes the 710’s can get very light in the rear end under hard braking.
For These reasons you will find less brake dust in the rear drums, by design they are not intended to be as effective.
Cum catapultae proscriptae erunt tum soli proscript catapultas habebunt.
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