Saturday, January 30, 2016

BSA Hornet Brakes, Cables & Forks

I have reached a good breaking point on the Interceptor and must shift gears to take care of my other bikes. The 70 BSA needs de-coking and re-timing, the Norton head gasket is leaking, and the Hornet needs tweaking.

Bikes safe and warm for the winter. 

Although the Hornet ran great last summer I did uncover a few areas of opportunity to improve its performance. The front brake works alright but is not what it should be, the forks leak a bit, and the cables are all too long.

I disassembled the Hornet front end and checked the brake shoe wear. Contact was good but could be better. I had taped sand paper in the drum and rotated the brake plate while working the shoes out. I found it difficult to get the tension adjusted right.  After dwelling on this for a while I came up with a method to make this process easier. A reversed wood clamp provided the adjustment necessary to lightly sand the shoes. The clamp was opened up as the shoes were worked in.

An easy method of fitting brake shoes. 

The brake cable is the Barnett variety with a coil at the brake arm connector and is longer than necessary. This was shortened and the factory adjuster, which was re-plated with my Interceptor parts, was put back on. The feel is greatly improved. Combined with better brake shoe contact I should have brakes back to 100%.

The brake cable fit with a ferrule and frayed. 

Brake cable soldered and ready to fit. 
The throttle and clutch cables received the same treatment and work much better now. 

Next it was on to the leaking forks. They were disassembled and fitted with 9/32 thick x 1 5/8 ID o-rings below the fork seals. This is not shown in the parts book but there is room for one. I have read the factory used string in this space but none came out when the forks were disassembled. Most of the oil was coming from the bottom damper bolts which were sealed (not very well) with an aluminum washer.  I put silicone sealer on the bottom of the damper rod mount and around the retaining bolt head. I think this will do the trick.

One last bone of contention is the new fuel cap which leaks slightly. I cut a 3 mm cork gasket to replace the rubber one which came on it. The rubber seal distorted quite quickly which was probably caused by the crap put in our gas here. I put an o-ring in its place which is a bit dodgy for a detailed restoration. Cork should seal well and not deteriorate like the original seal.

The new gasket formed to the opening well. 


The bike is finished but I will have to wait to try everything out.

On to the Norton. A bit of a leak from the push rod tunnels I think. 

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