A mates T.S.R outboard disc brake speedometer drive has packed up,so he asked me if i would fit a new one,as i had just fitted a new drive to my drum brake on my series 2.
I removed the speedo drive assembly from the disc,and sure enough,the two plastic drives had flat spots on them,so we ordered a new set,one metal (the drive wheel),and one plastic (the worm drive).
Fitted them today,in the same manner i had done for my own scooter,and no joy,the worm drive only connects if it is pushed up off centre.
Now,is there a difference between the original speedo drives and the outboard disc drives?
Speedometer drive
This may or may not help. I had a Lammy with an outboard disc. The speedo never really worked from the first time i built the wheel hub. I tried at least three worm/drive sets (all plastic)
just before selling it, decided to have one more go. I discovered that by fitting the ring to the stub on the hub (nice rhyme eh!) slightly further out (eg, towards the end of the stub) than previously, the drive worked fine.

just before selling it, decided to have one more go. I discovered that by fitting the ring to the stub on the hub (nice rhyme eh!) slightly further out (eg, towards the end of the stub) than previously, the drive worked fine.
Thanks for that,worth a try!
- vRSG60
- registered user
- Posts: 266
- Joined: Mon Apr 02, 2012 3:56 pm
- Main scooter: Lambretta Li125 Lambretta GP20
- Location: Barrowford, Lancashire
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I've had no end of bother trying to get new speedo drives work on my drum braked Lammy. I've now given up and fitted a GPS cycle speedo.
I get my kicks out on the floor.
