Page 1 of 1
1955 Model D150 - Gear Selector Arm

Posted:
Thu Feb 25, 2021 4:11 pm
by Big Al
I have just noticed that the external circlip is missing from the end of the gear selector shaft inside the selector box. The internal circlip is in place behind the selector arm.
When I try to push the arm further on, to fit the external circlip, the splined shaft moves inwards too.
I thought the arm should just pull off, so that I could see what is behind it, but it will not easily come off the splines. Should I try to lever it off?
Any ideas please?
The scooter is still on the bench at present. How can I tell from the position of the arm if the gearbox is in neutral, before I fit the cables? Should it be symmetrically placed inside the selector box perhaps?
(Otherwise I will need to jack up the scooter, and see if the rear wheel is free to turn.)
Re: 1955 Model D150 - Gear Selector Arm

Posted:
Thu Feb 25, 2021 5:57 pm
by jbcollier
Going from dim memory here but I don't think mine has an external clip either. The cover holds it in place. Not a good idea to pry with very much force as you could pop off the circlip inside the tranny. You would need to use a puller that grips around the selector arm and pushes against the shaft. Again, I don't think it's broken so leave it alone.
Yes, you have to rotate the rear wheel to be sure you have neutral. Any other way is a wild guess.
Unfortunately the cables do not go right through the selector arm. This means they are more easily pulled out in use. Once the inner is cut to length, solder the end to keep it together. I place a small ball bearing in the bottom of the clamp so there is something for the screw to push the cable against.
Re: 1955 Model D150 - Gear Selector Arm

Posted:
Fri Feb 26, 2021 5:15 pm
by Big Al
Thanks John.
I will leave the selector arm well alone then.
Mine is fitted with the detachable nipples that allow the cable to pass right through. There is a small disc inside each one, so I will make sure the grub screw bears down on that, and not the inner cable.
The photo at the bottom of Page 48 of my Lambretta Serviceman's Book First Edition shows the same set up as mine (apart from the outer circlip).
Re: 1955 Model D150 - Gear Selector Arm

Posted:
Sat Feb 27, 2021 2:32 pm
by jbcollier
Lucky! Mine are blind hole and a pain.
Re: 1955 Model D150 - Gear Selector Arm

Posted:
Sat Feb 27, 2021 3:52 pm
by Big Al
Could you not replace them with the type fitted to mine, as they just pop out of the selector arm without the cable in there?
Or perhaps yours are fixed in the arm?
Re: 1955 Model D150 - Gear Selector Arm

Posted:
Mon Mar 01, 2021 11:13 pm
by Big Al
I didn't think to make a note of this when I stripped the scooter down, but is the bottom gear cable at the handlebar connected at the bottom of the gear selector arm on the engine?
This would mean that selecting 1st from neutral would pull the bottom of the selector arm towards the front of the scooter.
Is that right?
Re: 1955 Model D150 - Gear Selector Arm

Posted:
Tue Mar 02, 2021 1:34 pm
by Big Al
When I say bottom gear cable at the handlebar, I mean the bottom one as the two cables transfer from the handlebar pulleys into the grey rubber protector (which covers the two holes where the outer cables seat).
Re: 1955 Model D150 - Gear Selector Arm

Posted:
Tue Mar 02, 2021 3:02 pm
by jbcollier
I meant to say my selector arm is blind holed, not the cable clamp.
Sorry can't remember but it is very easy to figure out.
Wheel off ground. Find neutral (half step between two gears). One way there will one only one gear (1st), the other way, two gears (2nd and 3rd). Next look at the shifter. One position will pull the cable while going from neutral to first. Now you know and can hook things up accordingly.
Re: 1955 Model D150 - Gear Selector Arm

Posted:
Wed Mar 03, 2021 11:36 am
by Big Al
Thanks John.
I managed to get the gear cables connected into the selector arm yesterday, and jacked up the stand to lift the rear wheel off the bench.
After adjusting the clutch, I was able to find neutral and then adjust the gear cables. On selecting first gear from neutral at the handlebar control, the selector arm rotated anti-clockwise.
Turning the control the other way rotated the arm clockwise and I was able to engage both second and third gears, so I had installed the cables the right way round.
Now I just need to trim both outer cables, as they are too long for my model, tidy up all the cables and tighten the alloy cable ties.