SF1 Drum Brakes

C

chrissoz

Senior member
Location
Sydney, Australia
Pulled these apart for a good clean and inspection.

Front only has the 2 small springs from the shoe to the brake plate. Rear has 4 springs - 2 small and 2 long - long ones running between the shoes. Does not seem like the correct setup - the only photo I can find is in the Laverda Pardise book P124 which has 1 short and 1 long! What is the correct setup?

Also re the comments on P 124 about not using split pins on the pad pivots - but to change to circlips - what is the general consensus on this - mine has split pins. Picture is the rear.

Thanks
 

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Chris, do you have a left-side brake pedal? I don't know if this applies to your bike but my 3c came with a right-side brake pedal originally and a crazy long rear brake cable that went over the rear guard to fit. I swapped to the much more sensible left-side rear brake but with the much more direct connection and short direct cable but it was insanely powerful and locked with a hard look after doing that change. The fix was swapping to much stronger big return springs between the shoes. How powerful is your brake and is it easy to control? Dont know about your spring question, be good to hear what the go with that.
 
chrissoz said:
Pulled these apart for a good clean and inspection.

Front only has the 2 small springs from the shoe to the brake plate. Rear has 4 springs - 2 small and 2 long - long ones running between the shoes. Does not seem like the correct setup - the only photo I can find is in the Laverda Pardise book P124 which has 1 short and 1 long! What is the correct setup?

Also re the comments on P 124 about not using split pins on the pad pivots - but to change to circlips - what is the general consensus on this - mine has split pins. Picture is the rear.

Thanks
Click to expand...
Nothing wrong with split pins, they are original fitment.
Originally, there were only the 2 small springs, they're insufficient, you want the two large ones. Dispense with the small ones.
Paul
 
Forgot to add the best improvement to my rear brake recently was lubing the links and connections, I used a spray can made by Penrite. Not WD40. Even better would be my go-to, Boat Trailer Waterproof Grease if it's all apart.
 
Are the brakes 1st. or 2nd. series drum?

1st. series had 2 large inner springs, 2nd. had just the 2 small springs, the actual return spring being fitted externally at the connecting rod of the levers.

If all is in good condition, both systems work well as designed. Both systems need to be carefully set up, slop eliminated and all shafts well-lubed. Shoes relined with decent material and skimmed to fit the drum make for a brake that requires next to no breaking-in and is powerful from the word go. Circlips succeded the split pins, neither has any great advantage. Circlips look neater...

Brake performance is also largely dependant on cable and hand lever/foot pedal condition and spec.

piet
 
2nd series - will fit new shoes machined to fit and lube all pivots on reassembly.

Vince - it is a lhs brake pedal on an SF1 - rear brake has always worked fine, plenty of stopping power and good control. I am hoping the new pads etc will improve the front brake.

Thanks for all the advice
 
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