Topic: Front brake calipers for CB550

[dicksoper]

I am refurbishing a 1974 Honda CB550 and after reading accounts of other vintage Honda riders I find more than a few accounts of wet brake problems.  The experience reported is poor stopping power at first followed by serious sudden grabbing.  Logic says drilled rotor(s) might solve the problem by allowing the hydroplaning water to escape.  I would be glad to hear from anyone having experience with the problem, and what solutions they found.  My bike has the standard single solid rotor.

[LesterPiglet]

I've never had a problem with mine. It is drilled though. I drilled it for the looks more than performance so never really experienced it solid.

[Garage_guy_chris]

heres a thread i started a while back on the topic, im running the same brakes as your CB550 on my CB450 currently

http://forums.sohc4.net/index.php?topic=142170.msg1612694#msg1612694

[OT7]

I drilled my rotor for the looks more than performance . Is a little  lighter in weight.

[strynboen]

 never have heat fading brakes on any of my bikes..so dont vant to drill stock parts..

(.in rain i its bettet to have hot disc..the vater is gone farster..i use to brake a bit before i komes to kritik plases  ,,so my disc are dryed up..and ready to bite.. the big problem on 400 500 750..are the pads...the orginal  pads ,vas raundet in a radius at the press side(piston side) to make the pad goes parelel to the disc..but aftermarked pads have not this..and make it schreme and give bad kontakt..and bad braking..it have to vear some 1000 km before it are grindet/veared to make full kontakt..its the radius turning caliper..it move not parelel to the disc..the orginal pad kompensate....for that

the disc  steel matrialare another problem...cast iron grib better..but veares farster aut

[Bodi]

I drilled the disc for ... don't remember - probably because I had access to a machine shop and it was a popular mod?
The wet braking improved massively. Before, stopping after a wash could be very scary. I think rain was never an issue except the first use of the brakes, maybe riding spins the water film off? Anyway, wet brake slip lasts a turn or so max now compared to the loooong wait with undrilled discs.
There's controversy over whether to slightly countersink the holes. I did, but factory drilled discs don't. The theories are A: the sharp edge of a bare hole scrapes off water or debris very quickly so don't countersink, and B: the sharp edge scrapes the pad off and wears them down quickly so definitely countersink.