Final drive done. Now the brakes

[Sleeper]

I completed the final drive inner and outer seal replacement. Thanks for the advice. 10 minutes with the heat gun and that bearing race fell right out. 20 minutes in the freezer and it slide right back in. I also repacked the wheel bearings and replaced seals.

I have been searching and reading everything on loop frame drum brakes to find ideas to make them better. One thing I noticed during disassembly of the rear was only the inner half of the rear shoes are making contact with the drum. Any ideas? I used some emery on the drum and shoes but don't expect any improvement.
I haven't pulled the front wheel off yet but that obviously is where I would like the most improvement. During my shake down ride, when pulling the lever it almost feels like a hydraulic system with a lot of air in it. The brake engages but if I squeeze harder the lever keeps coming to the grip. Could the cable be stretching?
I will pull the front wheel soon to inspect.
Thanks again,

 

[john zibell]

For the front brake, the linkage adjustment is critical. If the linkage isn't the correct length, both shoes won't engage at the same time. Disconnect the rod and note the location where each shoe engages. Note the location of the secondary shoe. Have someone hold the cable actuated shoe at engagement, then adjust the length of the rod to hook up where the second shoe engages.

 

[Amboman]

What John wrote. ^^ The angle of the arms is important too.
There is a lot of good information here, scroll down to the "brake" topics:
thisoldtractor.com/moto_guzzi_loopframe.html

A good quality cable is important too, many of the "off the shelf" cables from Europe have small, coarsely wound inner cable and the housing compresses giving the that stretchy feeling. Barnett makes the best ready-made cables, sold by MG Cycle.
mgcycle.com/index.php?main_page=product_info&cPath=135_144&products_id=5013
>One caveat with that cable: the switch used is from a Harley clutch cable to shut off cruise control when the clutch is pulled in. In that application it isn't under constant tension, as a brake cable it is. There is a foam ring inside the switch that compresses and the brake light will then stay on all of the time. I open up the switch (it snaps together) and replace the foam ring with a Buna-N o-ring of the same o.d.<

One other thing that is often overlooked: "centering the brakes". When reinstalling the wheel, I always tighten down the axle then the left pinch bolt, raise the from wheel off the ground, loosen the axle nut, spin the front wheel, apply the brakes quickly and hold them on while retightening the axle nut. It can sometimes make a very noticeable difference in both feel and stopping power.

 

[Sleeper]

The angles of the arms are just a hair off 90 degrees. According to the receipts from previous owner there is already a Barnett cable installed. The cable looks new. I adjusted the linkage. It appears that the secondary shoe was not making contact at all. Improvement on road test is 100% better. The brakes went from terrifying to scary. I know about scary brakes. I have owned 3 different airheads with ATE brakes.
Thanks for the help!

 

[john zibell]

If you change your arm angle, the adjuster for the brake cable won't have to be backed out as much. One or two teeth on each arm should do the trick. Also it will get you closer to 90 degrees. You have to completely remove the locking bolts as as the run through a groove on the toothed shafts. Do some line marking before removal so you know how far you have moved each arm. I think I see a mechanic's punch mark on the front shaft, but the slot in the arm doesn't appear to line up to it. If you line it up to the slot you may be good.