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 Post subject: 79 cr125 front brake
PostPosted: Fri Oct 02, 2009 10:42 am 
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Joined: Wed Mar 05, 2008 11:15 pm
Posts: 109
i have seen some where that cr 480 front brake will fit the 79 cr125 front hub is this true i have a chance to pick up an 83 cr 480 front backing plate free thanks jd


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 Post subject: Re: 79 cr125 front brake
PostPosted: Fri Oct 02, 2009 9:30 pm 
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Joined: Fri Feb 27, 2004 10:20 pm
Posts: 906
Location: San Clemente, CA
If you want a double leading shoe front brake you'll need to pick up backing plate, brakes, and hub as a set. Donors could be from 1981 through 1983 but don't try and mix and match parts.

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Michael Stiles
1979 Honda CR250R Elsinore | 2006 Husqvarna SM510R | 2007 Service Honda CR500R-AF


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 Post subject: Re: 79 cr125 front brake
PostPosted: Sat Oct 03, 2009 4:20 pm 
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Joined: Sun Nov 30, 2008 12:10 pm
Posts: 1010
Location: Connecticut, USA
Having just fitted a DLS brake to my '74 CR125, I can tell you that making sure the backing plate/shoes fit the drum (I'd recommend following redrocket190's advice) will likely be just one of your concerns. The backing plate slot has to engage the stub on the left fork slider, the shoes must ride roughly centered in the drum, the axles have to be the same diameter, the combined width of the hub and backing plate must be less than the width between the fork slider axle bosses, the brake cable adjuster should roughly line up with the fork tube to allow a smooth cable run, the linkage must clear the fork slider, etc. etc. The easiest way (provided the steering stem cooperates) is to swap out the entire front end - forks, wheel/brake, and triple clamps - as I'm doing on my RM. I realize it's not cheap.

If your '79 CR125R drum is 130mm (every Japanese drum I've seen has this dimension cast into the interior of the hub), the early-80's YZ/IT DLS brake setup I used may be an easier retrofit for you. It has the advantage of a forward linkage that clears offset fork sliders, and was made with two different positions of engagement-stub slot.

My DLS brake is incredible - I'm actually a little worried about bending the fork tubes. :D It doesn't have the ultimate power or fade performance of my YZ's disc, but it initially comes on stronger, believe it or not. A novice rider would definitely think the DLS was a more powerful brake.

Even if some machine shop time is needed, in my opinion the end result will be worth it.

Ray

Attachment:
Front Brake (small).jpg
Front Brake (small).jpg [ 7.22 KiB | Viewed 8444 times ]

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'74 CR125M (175cc), '75 MR175, '82 RM250Z, '08 YZ250F, '14 Zero FX electric, '14 Zero MX electric, '18 Alta MXR electric


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 Post subject: Re: 79 cr125 front brake
PostPosted: Sun Oct 11, 2009 10:11 pm 
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Joined: Wed Mar 05, 2008 11:15 pm
Posts: 109
just scored a compleat 82 cr480 front brake asemb. with axel off ebay :D now all i need are spokes to mount the 21 in. excel rim.


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 Post subject: Re: 79 cr125 front brake
PostPosted: Fri Oct 16, 2009 6:55 am 
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Joined: Thu Jan 05, 2006 1:35 pm
Posts: 344
Ray: what parts did you use to do this???
Thanks!


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 Post subject: Re: 79 cr125 front brake
PostPosted: Fri Oct 16, 2009 7:58 am 
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Joined: Sun Nov 30, 2008 12:10 pm
Posts: 1010
Location: Connecticut, USA
mitchie,

The following was required to fit this brake to the '74/'75 CR125M forks:

Suzuki front hub, RM125/250/500 ('83) RM500 ('84), P/N 54110-14120 or 54110-14121, no changes needed

Yamaha DLS brake plate, '83/'84 YZ125, '81 YZ250, '80/'81 YZ465, '81/'82 IT465, P/N 3R5-25121-01-98
(fork stub engagement slot should be right next to the short linkage lever)

Brake plate diameter reduced .15", fork stub engagement slot slot extended .1" towards axle & deepened .07", .3" milled off center axle boss

Fork leg axle bosses drilled for Honda 44301-304-971 15mm axle (70's CL175, CB175, CB200, SL175, XL175, etc.),

Spacers: one .172" RH spacer used w/Suzuki hub spacer, two .3125 (5/16") axle spacers (used outside forks to take up excessive axle length), one .41" spacer between backing plate and wheel bearing

NOTE: The '83/'84 YZ125, '83 YZ250, '84 YZ490, '83/'84 IT490, and '83/'84 TT600 use an aluminum DLS linkage, which is lighter and better-looking than the steel linkage.

Ray

_________________
'74 CR125M (175cc), '75 MR175, '82 RM250Z, '08 YZ250F, '14 Zero FX electric, '14 Zero MX electric, '18 Alta MXR electric


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