Outboard shocks vs internal progressive springs

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victor
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Currently rebuilding my lambretta I will shortly need to invest in new front dampers and uprated springs.

New good dampers (BGM) seems to be around £180, and on top of that of course I'll need a good pair of internal progressive springs.

Question is if there's really any reason for going for this setup or if it isn't better to get outboard complete shocks-dampers and get rid of these internal springs altogether?

The reason for the internal springs on the Tv175 (and other models) is that they only added fairly simple external shocks to the shock solution they already had back in the 60s. Today I suppose external/outboard complete shock absorbers with dampers would have been used.

Will the 6mm pin on the fork link be enough to support external shocks? If so, which are some good external shocks that can be recommended?

Cheers Vic
Daggs
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IMO it would be unwise and dangerous to ride without the internal springs. Even if fitting top quality external dampers.
It's worth remembering Innocenti fitted dampers to their scooters to damp on wheel drop only.
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victor
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Daggs wrote:IMO it would be unwise and dangerous to ride without the internal springs. Even if fitting top quality external dampers.
It's worth remembering Innocenti fitted dampers to their scooters to damp on wheel drop only.
Hi Daggs,

Would you mind expanding on why it would be unwise and dangerous?

When you say that the dampers damp on wheel drop only, are you saying they only did rebound damping?

Cheers Vic
Daggs
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The internal springs are a very strong and safe system (if a little rudimentary). I fear outboards would place too much stress on the link mounting studs.
Innocenti outboards did not damp on wheel rise (the internal springs deal with that) only drop. What you call rebound (i think)
If you can get your hands on outboard dampers used by S.I.L. (escorts) you can try this and feel/see the difference.
servetakid
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Arent these fully outboard? I dont know what links you need?

http://www.pmtuning.co.uk/sc0021
thesx200
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The last few bikes i have built i have used the outboard shockers and scomadi links from Frank Sanderson .
would not use anything else now .
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DigDug
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Image

I'm pretty sure that this type of suspension knocks Lambretta's original setup into a 'cocked hat'.

If you've ever thrown a GTS around you'll appreciate a well set-up scooter can feel like. This handles just like one.

It's PM tunings outboard offering, complete with their links and you can adjust your damping to suit.

Supplied by the aforementioned Frank Sanderson.
Did you have to do that?
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victor
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Daggs wrote:The internal springs are a very strong and safe system (if a little rudimentary). I fear outboards would place too much stress on the link mounting studs.
Innocenti outboards did not damp on wheel rise (the internal springs deal with that) only drop. What you call rebound (i think)
If you can get your hands on outboard dampers used by S.I.L. (escorts) you can try this and feel/see the difference.
I'm afraid of that too regarding the mounting studs. Besides this I can't see any advantage with the internal system... As I have a Tv175 I'm well familiar with the Escort dampers :)
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victor
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servetakid wrote:Arent these fully outboard? I dont know what links you need?

http://www.pmtuning.co.uk/sc0021
Cheers for that, looks ace and gas dampers are the s**t on the front end, my GTs became a totally different bike (although the £300+ rear BiTubos werent even noticeable).

PM lists:
Parts include Scomadi links, pivot bush kit using stainless parts, lower and upper mounting kits suitable for single or double disc conversions, we also offer a upper mounting weld on service for all our Scomadi forks.

Advantages all the way...

Fitting outboard shocks to lambretta forks allows you to remove all the internals... springs, guide rods, rubber buffers, etc. putting the suspension on the outside of the forks where they can be quickly and effectively adjusted without having to tear down the forks.

The benefits are clear when the following points are considered...

• Wider stance for better fork link/wheel stability during cornering and braking resulting a positive feel in handling.

• Air assisted Compression adjustment 50 to 110psi range

• Slow to Fast rebound adjustment via screw adjustment 15 clicks

• Spring preload using pinch ring nut. (80lbs spring)

• In built rebound and bottoming rubber buffers

• Integrated spring and rebound damper fully serviceable.
Does that mean that they contain the fork links as well...? :)
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victor
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DigDug wrote:Image

Supplied by the aforementioned Frank Sanderson.
That looks ace! A bit wide though, hope it will fit under a Tv fibreglass mudguard...
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