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LI special - swansong project?

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Re: LI special - swansong project?

Postby dickie » Mon Mar 15, 2021 8:05 pm

I've just done some bench tests and the original one gives 0.6mm of pad movement for 5mm lever action. The better remade one only gives 0.3mm.

So now I know the problem, I need a solution. And sadly, that looks expensive unless I get loads made and sell them. I'm not really planning that as I suspect there's a very limited market, but my mate is very good 3d cad guy and he'd help for free. I may look into it.
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Re: LI special - swansong project?

Postby Warkton Tornado No.1 » Wed Mar 17, 2021 1:11 am

The differences in production methods & quality are obvious, not only between the two remade copies, but the OEM type shown by Storkfoot have a truly linear ramp.

Of the two bootlegs, the better quality version already shows signs of a wear groove whilst the other looks as if it should play like a record.

It would be interesting to measure the surface hardness of the OEM vs the cr@pski items, but my money would be on Innocenti quality control having got it spot on decades ago.

The only function the pattern may have could be to pride carriers for three hardened inserts, but you may as well manufacture from scratch.

I wonder whether an alternative method to the cam might be feasible & discrete. My initial thoughts are to look into linear ball screws with a round housing retained by the current circlip & a replica lever element turning the ball screw by being affixed via a square as drive.....
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Re: LI special - swansong project?

Postby dickie » Wed Mar 17, 2021 7:41 am

Yes, I noticed the witness marks and even though I've been messing with them a lot, they can't have seen many more than 100 applications each. Hardness testing would be worthwhile if I do think about getting some quality ones made just to provide a benchmark of what not to use!

I know what you're saying about a linear ball screw but the pitch is pretty high on these cams, I doubt a ball screw will provide 1mm travel for 30 degrees of rotation (VERY approximate numbers). But it would be a far better solution. I'd prefer to stick with original design and just get it right. Innocenti seem to have done 60 years ago, so copying shouldn't be too hard!
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Re: LI special - swansong project?

Postby Storkfoot » Wed Mar 17, 2021 9:40 am

Why not buy a rusty old original and use that as a starting point?
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Re: LI special - swansong project?

Postby dickie » Wed Mar 17, 2021 2:32 pm

Storkfoot wrote:Why not buy a rusty old original and use that as a starting point?

You're absolutely correct. I've bought one and am waiting for it to arrive. I wonder how many are just in need of a replate and new bearings like yours? Hopefully this one will be as I'm rapidly building a collection of expensive crap actuators.

I know I can design an excellent one, better than original but I'm not sure of either the market or costs involved as I'm electrical by profession. However my friend is a mechanical engineer and a fellow bike enthusiast. He has yokes specially made and sells them worldwide, so maybe he'll be selling actuators later this year?
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Re: LI special - swansong project?

Postby dickie » Wed Mar 24, 2021 8:34 pm

Storkfoot wrote:Why not buy a rusty old original and use that as a starting point?


So, I bought an original one in scruffy condition but like my mate's, it's night and day compared to the remade ones.

I've stripped both the original ones as well now, and the difference is the dimples. All of them are radiused, but the original have a much larger radius and therefore more linear in their action as well as more initial movement.

I measured both original ones and they give 2.6mm of displacement for 45 degrees at the lever. The remade one i measured was only 1.7mm; that was the better one of the two.

Image

The two in the foreground are the original ones. I'm not sure how obvious it is from the photo but there's a really big difference in the shape of the dimples.

I've also realised that the 'week' spring issue isn't really an issue, but rather that they're such a bad fit that they need a stronger spring to move the lugs through the channels.

What a palava.
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Re: LI special - swansong project?

Postby Storkfoot » Wed Mar 24, 2021 9:47 pm

A classic case of the original parts being the best. In this case, of course, without stripping the remade actuator down, you can’t see the differences.
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Re: LI special - swansong project?

Postby dickie » Wed Mar 24, 2021 10:30 pm

Storkfoot wrote:A classic case of the original parts being the best. In this case, of course, without stripping the remade actuator down, you can’t see the differences.


Absolutely. The remade casa one looks better quality than original and is erynicely made, but that's not great comfort if it doesn't work as well.
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Re: LI special - swansong project?

Postby Warkton Tornado No.1 » Thu Mar 25, 2021 10:25 am

Interesting...

If the OEM component is a stamped pressing, in a steel that would be tough, the indentations would have hardened the area locally. Ideal, wear resistant 'stampings'

That's good as it would not be too difficult to replicate a one off, but small batch manufacture would not be too expensive IMO.

Ideally a tool room engineer is reading this & can rise to the challenge :D

I have a 10 plus tonne hydraulic press that I need to recommission.

We almost have the makings of a plan ;)
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Re: LI special - swansong project?

Postby dickie » Tue Apr 06, 2021 7:30 pm

While waiting for the brake actuator parts to come back from plating, I don't have any big jobs i want to get on with so just fiddling about really. But I set the clutch lever up.

Really pleased with it. It's 2 finger light. We'll just have to wait and see if it slips but I doubt it. It seems like I've achieved what I intended, which is nice. :D
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Re: LI special - swansong project?

Postby dickie » Mon May 03, 2021 4:35 pm

The plater eventually got my parts done. The old bloke who owned the business has put his son in charge, so now it takes 3 times as long! It's a little back street place and he calls himself the plant đirector! Harrumph.

Anyway, I've settled on an original actuator, just replated and with new bearings. Thanks to storkfoot for showing us how to refurb them. I've sold on all the others I amassed and feel a bit guilty for doing so, but I was honest about what they were, so I can just about get to sleep.
Image

Next I decided to finish the wiring. I hate this bit, it's just confusing and fiddly. At this point, I should maybe point out that I've served an apprenticeship and worked in electrical controls for 30 odd years up to engineer. And I still hate it. :lol:

The sidelights don't work and I'm very (but not completely) confident that my cheapo ebay switch is the issue. I never use the sidelights anyway.
Image

Meanwhile the CDI on my other lambretta failed last weekend. I've been using cheapo ebay ones for Chinese quad bikes. Bearing in mind that I'm a very low mileage rider, I'd say they're unreliable. So, I've changed both over to using Anthony Tambs CDIs. These were almost a straight swap and although 3 times the price, that still only makes them £18. They don't seem to run any better or worse, but the spark is much brighter. As for reliability, we'll just have to wait and see; I've still got a few Chinese ones I can carry around just in case.
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Re: LI special - swansong project?

Postby Storkfoot » Mon May 03, 2021 5:23 pm

Tell us about the front brake light switch please?
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Re: LI special - swansong project?

Postby dickie » Mon May 03, 2021 5:37 pm

Storkfoot wrote:Tell us about the front brake light switch please?

It's from a PX. You lose about 1mm of cable travel by using it. But, the last few mm of cable travel are just bending the mechanism rather than applying force, so that's not a huge issue.

Also, where I've placed it isn't ideal; I've found that it gets in the way of the speedo. It would be better placed behind the horncast (harder to get at) or closer to the brake lever (might foul headset top etc). I suspect I'll finally place behind horncast.

I've used an MB universal loom which already has the wires in for this, so it's dead easy to wire up; one wire to each side of switch.
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Re: LI special - swansong project?

Postby Storkfoot » Mon May 03, 2021 9:03 pm

I have a weird MB loom with a couple of extra wires that seem to run the full length of the scooter. If I had seen your thread before I set up the front brake on my GP, I’d have probably fitted a front brake switch too. That said, I tend to apply both brakes at the same time anyway.
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Re: LI special - swansong project?

Postby dickie » Mon May 03, 2021 10:45 pm

Storkfoot wrote:I have a weird MB loom with a couple of extra wires that seem to run the full length of the scooter. If I had seen your thread before I set up the front brake on my GP, I’d have probably fitted a front brake switch too. That said, I tend to apply both brakes at the same time anyway.

Yes, I think i only did it because it was easy :lol:

The other wire might be the one they put in for the fuel light, which I'm using.
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Re: LI special - swansong project?

Postby Warkton Tornado No.1 » Tue May 04, 2021 2:03 am

It's all looking very nice.

As you are running damper gaitors, perhaps a gaitor over the inner cable (as soon as you've made the soldered cut to remove excess) might be complimentary. Even the Indian gear/clutch gaitors can be made to function with patience. Removing all of the moulding flash takes time, but worth it IMO.

Same reason, as in being 'complimentary' but i reckon the lower damper nuts could be swapped for dome nuts for that extra finishing touch.

Just my opinions :roll: but I hope you don't mind me suggesting them....

As for front brake actuator switches for brake lights, I thought there might be a brake cable set available with 'non-contact' proximity switches, but I might have dreamt that up. A decent electrician might be able to tell you. Do you know any? :lol:
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Re: LI special - swansong project?

Postby dickie » Tue May 04, 2021 3:40 am

A proximity switch is a nice idea, but I can't think of where to mount one other than at the bar lever or on the actuator; both of which are just too ugly to contemplate.

I think I've got some nyloc dome nuts for the dampers. Or a dab of nutloc will suffice.
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Re: LI special - swansong project?

Postby dickie » Tue May 04, 2021 6:55 pm

Warkton Tornado No.1 wrote:It's all looking very nice.

As you are running damper gaitors, perhaps a gaitor over the inner cable (as soon as you've made the soldered cut to remove excess) might be complimentary. Even the Indian gear/clutch gaitors can be made to function with patience. Removing all of the moulding flash takes time, but worth it IMO.

Same reason, as in being 'complimentary' but i reckon the lower damper nuts could be swapped for dome nuts for that extra finishing touch.

Just my opinions :roll: but I hope you don't mind me suggesting them....

As for front brake actuator switches for brake lights, I thought there might be a brake cable set available with 'non-contact' proximity switches, but I might have dreamt that up. A decent electrician might be able to tell you. Do you know any? :lol:


I felt like I was being told off for posting images of unfinished work. So here it is done reet. :D

And I did cut the flashes off too. :D
Image
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Re: LI special - swansong project?

Postby Toddy » Tue May 04, 2021 6:57 pm

[/quote]

I felt like I was being told off for posting images of unfinished work. So here it is done reet. :D

:lol: :lol: :lol:
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Re: LI special - swansong project?

Postby shane BBoys » Wed May 05, 2021 9:21 pm

Dickie.
I also used the T5 front brake light switch cable works a treat, I have the same remade disk brake and find it is shocking.
Maybe should have followed your advice while I had it in bits to fit the sintered pads.
Cheers Shane.
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