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Author Topic: Rear brake  (Read 1420 times)

bakio98

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Rear brake
« on: April 08, 2009, 05:27:46 PM »
Has anyone heard of a retro change over to get rid of the rear drum to a disc brake? The lack of braking power sort of scares me.

Darwin_R65

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Re: Rear brake
« Reply #1 on: April 08, 2009, 05:47:51 PM »
Don't forget braking is probably 75% front 25%rear, so if you boost the rear end you won't improve things too much, probably just make it easier to lock up the rear.

When you apply the brakes all you weight transfers to the front and the rear wheel lifts slightly.

You're better off looking at adapting the front wheel to a twin disc system.

John

Offline nhmaf

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Re: Rear brake
« Reply #2 on: April 08, 2009, 07:19:05 PM »
Actually having a rear disk makes rear-wheel removal/replacement somewhat more difficult, and over the years some have complained about the relative fussiness of the rear disks on airheads - they are more powerful, but again one has a much greater tendency to lock up the rear unless carryin a passenger to help keep the rubber down.
« Last Edit: April 08, 2009, 07:19:22 PM by nhmaf »
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Offline MrRiden

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Re: Rear brake
« Reply #3 on: April 08, 2009, 08:46:59 PM »
There are tricks to making the rear grab better. Scuff the drum, new shoes, file the cam to make perfect contact with the shoe [or visa verse]
Reline shoes with softer pads but the best is to go over the front disc and make sure everything is in top nic. You could spend many hours on the breaking system. Time well worth the while. I've been on single disc R65's that were superior to dual disc models, It's all in attention to details. I think there are no less than 3 different disc pad compounds and 2 different discs available off the shelf. as good as all this is I've never seen an R65 do a "stoppie" tho.
rich
"We can't stop here. This is bat country".

Offline nhmaf

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Re: Rear brake
« Reply #4 on: April 08, 2009, 10:04:24 PM »
... and hopefully your braking system doesn't become a "breaking system"
 ;)
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Offline steve hawkins

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Re: Rear brake
« Reply #5 on: April 09, 2009, 03:41:54 AM »
I have also heard that the rear disc set-up is less that ideal.  

I have even heard of people converting back to a drum setup.

I would make sure your drum set-up is work properly first - check the angle of the connecting rod to the actuating arm  - it can make all the difference.

Cheers
Steve Hawkins R100 (that wants to be an R65)

drewboid

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Re: Rear brake
« Reply #6 on: April 09, 2009, 07:57:08 AM »
My fiance had problems making quick stops - adding the second front disk was the cure. We used the original 12mm master cylinder and changed to SS brake lines. Much easier than adding a rear disk.

Offline Justin B.

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Re: Rear brake
« Reply #7 on: April 09, 2009, 09:24:56 AM »
Everything I have read indicates the drum (when working properly) is all you need.  If you can lock up the rear tire then you can't get it to "grab" any more!  A lot of people complain about the rear disc brake claiming that it does not brake as well as the drum but I can lock up the rear wheel on all of mine, disc or drum.

I suppose it would be possible to fit the rear disc components from an early R100RT or R100RS but I've not done it.  You would need the rear wheel, caliper bracket, rear axle, caliper, lines, rear master cylinder w/linkages, brake fluid reservoir, etc.
Justin B.

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