Best reverse pull inboard disc brake?

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storkfoot
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I'm just about to set up my inboard disc brake properly. I have stripped it down and cleaned it up but I can already tell that even with the reverse pull, it's not good enough at the moment. So, before I take it for its first MOT, I'm planning the following to make it as good as possible:

New sintered pads (I don't know the history of the ones in there. They look ok but ....)
Get the faces of the disc machined at an engineers (there is a bit of pitting on both sides)
Remove the inner circlip to allow the disc to "centre" easier when the brake is applied.

Other than going hydraulic, which I don't want to do on this scoot, is there anything else I should be looking at please, or are any of the above ideas a bad move :?:
bristolmod
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sintered can be good but noisy at times.
machining the actual disc should help
removing the circlip can help but can "rattle" at times.

I found that a heavier guage inner cable is better (less stretch?) and that the outer needs to be the "correct" cut length (too long and its not as efficient)

The main improvement is the actual adjustment of the static pad- a small adjustment of the locking nut can make a major difference so its worthwhile spending some time getting it spot on.

Finally, its worthwhile ensuring that the holes on the actual disc are clean and that the pins themselves are smooth.

Chris-
Scootering since 1968.
Muppet
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cable choice inner and outer
C’est la vie
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jason frost
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Circlip with internal tabs and what about making the arm longer?
bristolmod
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another major factor is the brake pads naturally.

However, in the original parts book dated 1962 which covered all Slimstyle machines and the new "flagship" scooter the TV175 S3, it shows the actual brake pads as 2 seperate components- the pad itself, which they call the "tablet" (part no 1974 4063), and the metal backing plate which they call the "disc" (part number 1974 4062)

It appears that originally, the braking material and the metal backing disc were seperate components.

To cut a very long story short, I had a pair of these metal "discs" in a box of spares which I'd had since the 1960's and didn't have a clue what they were for.

I had similar problems with poor braking on a TV175 so I inserted these odd items between the existing pads and the actuating mechanism on one side and the adjuster on the other and it improved matters greatly- simply by increasing the overall thickness of the pads.

Now whether or not the 2 part component was dropped by Innocenti shortly after inception to a one part "pad" with a consequent decrease in overall thickness I don't know- one of the unexplained Lambretta "quirks" possibly?

Chris
Scootering since 1968.
storkfoot
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Thanks for those pointers. I have the thicker cable but, yes, I have at the moment left my cable loop a little too long. I'll trim it some more too.

I don't mind the rattle when you take the circlip out as you only ever notice it when you're pushing the scoot (this should not happen too often :-) )

Jase, what do you mean about the circlip "with tabs" please?
dave wheeler
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run a 13/32" drill bit through the holes to make sure the disc fully floats, if you then find the rattle unaceptable, or if your mot mannie has a problem with it put the anti rattle circlip back in. outer cable length is crucial,as is static pad setting, my disc on my TV is awesome, 1 finger pressure all that is required, nearly as good as the outboard hydraulic i had on my GP
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sean brady scooters
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if your scooter is pretty std then all of the above advice and help is good ,but if you perhaps have a higher performance engine capeable of much higher speeds than std there are some other things that you can do to avoid brake fade ...as internal disc/pads can overheat quite easily especially when braking from much faster speeds ..an enlarged air scoop on the back plate can help as well as drilling some holes through the disc to aid air flow and cooling .
Sean Brady Scooters - 01765 690 698
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jason frost
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storkfoot wrote:
Jase, what do you mean about the circlip "with tabs" please?
Like the one you can get for the kickstart but with the tabs on the inside.
storkfoot
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It is a 16 or 17bhp GT186, so yes, it is pretty nippy and this is why I want a well set brake with no fade.

Thanks for all the ideas. I'd forgotten there were so many tweeks :D

I'd forgotten about getting the disc drilled which is surprising seeing as the one on my TS1 is :!: That is a hydraulic inboard disc though.

I should receive a new set of pads tomorrow so, over the weekend, I'll have a mess around. Thanks again :D
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