Topic: A Few Questions: "Sticking" Brake and Bulbs...

[Justin]

A couple of questions for those of you that have already "been there, done that"...

I'm cleaning-up a '75 CB400F and a couple of things I'll need to address when I get started are:

1. Sticking front brake. I don't have the bike here, so I can't look at it, but I believe the brakes on this bike are supposedly of the "floating" variety, but for whatever reason, they want to stick...if I remember correctly, there is a little spring on top of the brake assembly that I'm thinking may need some lubrication, or maybe it's something else...what do you recommend?

2. I noticed during my preliminary check that a few of the bulbs are burnt out (one front turn signal, one back, maybe the brake light as well)...can you purchase the replacement bulbs at a local autoparts store or are they "motorcycle specific" and dealer only items?

Thanks.

[TwoTired]

1.  Fairly common problem.  The front caliper piston sticking because the brake fluid wasn't changed regularly.
http://sohc4.us/node/50

2.  While not motorcycle specific, the stock bulbs are lower wattage than what the auto parts stores normally carry. 1073 (single)and 1043 (dual) are what you are after.  The 1157 and 1156 common replacements are higher wattage and don't work well with the stock flasher unit.

[Bob Wessner]

Are you sure the bulbs are burned out? Maybe just some dirty connectors??

[eldar]

It is possible to have dirty connectors. Also some people put on this yellow goop when they put in bulbs, I suppose to prevent corrosion. That goop prevents bulbs from working since it would prevent good connection.

With the brake, dot3 had a tendency to accumulate moisture which corroded the piston and caliper walls. This prevents the piston from moving properly.

You must remove ALL old fluid from your master cyclinder, brake line, and caliper. The piston must be removed and cleaned and possibly replaced if there is bad pitting.

The caliper walls must be cleaned and a dremel with a wire wheel works great for this.

There is a brake FAQ on the site that should give you more info.

You will also want to see about cleaning your master as well and maybe rebuilding it.