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'71 Front Brake



Initially I found the front brake on the '71 to be very underwhelming, so much so that I felt it was down right dangerous. The brake on my '69 Bonneville was considerably better, albeit still drum brakes, but a close match to the disc brake on my sons '74 BMW R90.


These are the steps that I took to try to improve them, at least to match those on the '69.


The first thing that I did was pull them apart again and clean and check everything to make sure nothing was sticky or binding. No change.

The next thing I tried was to bed the new shoes with sandpaper attached to the drum. I had heard that this was supposed to really be the fix so was hopeful. Prior to reassembly I made sure that every thing fit well and was well lubricated. This seemed to help a little but was still not really inspiring.


I had heard about longer brake shoe levers so did a little research and found some at a dealer that I had purchased from before. They came in a package with TriCor labeling all over them so assume that this was something that was available back in the day. However, that is just conjecture on my part.





However, upon reassembly I found a couple of problems.



This is what I had to do to get the handle bar lever to adjust to something reasonable. I went back and turned the bush around on the rear lever and that at least got the adjuster back to something reasonable. But, the brakes were not really better. In fact they were a lot more squishy with the handle bar lever burying itself against the bar under four finger full on stops. This would make sense as the longer drum levers meant more travel at the handle bar to move the shoes the same amount.


Next I noticed this.




Understand, the snail adjusters were fully adjusted. And, in addition to that, while the snail adjusters, if loose, can cause the lever to travel farther to contact the drum with the shoe when the brake is applied, it doesn't really affect the position of the drum levers at rest.


I realize that this angle business is a minor point but I was grasping at straws now.



So I made the longer brake push rod on the left to reposition the rear lever.



And got this.


This also had the effect of allowing me to turn the rear brake lever bush back around as it is supposed to be and still give me a normal adjustment at the handle bar lever.


At this point I had to admit that, while the brakes were better, they still left much to be desired. I had pretty much exhausted all the ideas that I could come up with, leaving me with only two reasonable explanations. Number one, I only had about 100 miles on the bike so perhaps more miles would better seat the shoes. And, number two, I wondered if by chance the new shoes that I had might have been aimed at AHRMA racers and had a compound that needed to be heated to really function well. For now I will just try to put a few more miles on the bike and hope that the brake improves.




Up date!!


March, 2013.


During bike week and a week or two before and after I managed to put about 500 miles on the bike. The front brake has improved some and so I am hopeful that things will gradually get better. Guess I will just wait and see.





April, 2013

The front  brake has continued to improve so I think that wearing in or perhaps hardening from application of heat is helping.




Eventually, during the cafe build for the bike which was accompanied by modern levers, I removed the extended brake cam levers and replaced them with the originals. I found that this actually worked better with less squishiness. The modern brake levers helped make this work.




After about 2 years and 2000 miles the front brake still leaves something to be desired. It's  better and tolerable but still not as good as my '69. I have observed something with them that suggests that they will actually stop better than they feel like they are stopping. If I grab the lever and bury it, initially, the brakes don't feel like they are going to stop. However, within perhaps a half a second they come on much stronger and the bike does actually stop pretty well. This sounds like they just need to be heated to work. So, for now, I just make sure I pay attention and try not to get in an "emergency stop" situation. I guess that's the down side to living with "vintage" in some cases.