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Ok, so I got a new shock for my 180ss and all seemed well before I set up the front brakes. Here's the issue:

The front dives free fall style. Like, no damping. Was I supposed to fill it with oil or something before installing? Do they just dive that way normally? My Bajaj does, but I thought the 180 would be stiffer/smoother.
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Hooked
1972 Vespa GTR, 1963 Lambretta LI 125, Royal Alloy GP125
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My gtr dived horrendously and I thought that's just how it was. I upgraded the brake shoes to newfren grooved and it is completely different, I have a nice firm brake lever and progressive braking without the Instant dive.
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bodgemaster
63 GL, 76 Super (x2), 74 Primavera (x2), 79 P200, 06 Fly 150
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Check this thread:

Fronk shock
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dsnyder586 wrote:
Ok, so I got a new shock for my 180ss and all seemed well before I set up the front brakes. Here's the issue:

The front dives free fall style. Like, no damping. Was I supposed to fill it with oil or something before installing? Do they just dive that way normally? My Bajaj does, but I thought the 180 would be stiffer/smoother.
What shock is it?
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Its the regular repop one.

Here is an example (cant remember where I bought it lol)

https://www.scooterwest.com/vintage-gs160-ss180-original-style-front-shock-094396p.html

Its also super squeaky
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Brake dive is inherent in the design of the suspension. A stiffer spring usually helps with excessive dive.

You sure it's the shock that's squeaking? Check the mounts, the spring and the pivot pins and make sure everything's lubed up and tightened down.
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Thanks Socal, I will check- is there oil in this shock (or should there be?)
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I don't believe so. I think it's just a spring inside a tube. One of the SS guys can confirm.
Forum member supplied image with no explanatory text
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Molto Verboso
'64 Motovespa 150S (177) , '65 VBB, '66 Allstate SF, '66 180SS
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That aftermarket (Pascoli) shock damper can't be rebuilt. It's not like the original ones that can be rebuilt with new seals and fresh oil. It either has oil in it from the factory or it doesn't. Most likely it does. If the shaft pulls in and out slowly with effort, then it had oil in it.

Note: None of the parts, spring included, from that Pascoli shock are interchangeable with the old original shocks.
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Oof. Off to search for an original.
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Well, if you're sure it has no oil in it, then I'd send it back.

The front shock for SS180/GS160 is very specific to those two models. Nothing else will work on them and that shock will not work on anything else. The Pascoli is an adequate copy, but as usual, it's not as good as an original. The physical dimensions are slightly bigger, and as I said, it's a non-rebuildable (disposable) unit. The irony in all this is that Pascoli actually sells the rubber seals needed to rebuild an original one.
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Molto Verboso
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nomadinsiam wrote:
That aftermarket (Pascoli) shock damper can't be rebuilt. It's not like the original ones that can be rebuilt with new seals and fresh oil. It either has oil in it from the factory or it doesn't. Most likely it does. If the shaft pulls in and out slowly with effort, then it had oil in it.
So, can you remove the spring and see if it is dampening ? I'd think it would be impossible to tell with the spring installed.
New replacement parts that don't work as well as originals is just so stupid and getting boring. " Chassis STANDARD - like original and Grade A - perfect repair" Yeah, right.
Or... you could always 'upgrade' to this for a few bucks more ( ha!) .... https://www.sip-scootershop.com/en/product/shock-absorber-sip-performance-race-front_76004FSB
The original on mine works perfectly.
Typically, the spring is the suspension and the dampener just limits the rebound or compression speed. On early cars this was accomplished with adjustable friction plates.I am not sure if the relatively slow rate of brake dive would be affected by the shock. I know that a heavier spring on my Motovespa pretty much cured the dive with the same shock installed.
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Yes, of course. Just unscrew the top nuts and the top half of the shock will unscrew from the dampener rod. The spring then comes right out. That is as far as it goes. The dampener is a sealed unit with no way of rebuilding. Like I said (but probably not clearly enough), pull the dampener rod in and out to test if it has any oil in it. If there is resistance and a sucking noise, then it's got oil.

It's not a bad shock and should be fine, if it has oil it. These days nothing surprises me though. If it came shipped with no oil in it, that would be messed up and unusual, but not a surprise.

My original shock, after changing the rubber seal and putting in new oil, is great.
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Moto64 wrote:
https://www.sip-scootershop.com/en/product/shock-absorber-sip-performance-race-front_76004FSB
That thing may perform great, but it is ugly as sin. I couldn't stand looking at it if it were on either of my bikes.
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Yes, that was a bit of 'tongue in cheek'.
If it turns out there is oil in the damper portion ( nothing surprises me any more either) , can the spring be up-rated ?
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Ok- I'm gonna take it off this weekend, remove the cap and see whats what.

Would a spacer help with spring rate? Also, can I maybe put a rubber sleeve around the spring to quiet it down? (it squeaks a bit) Or maybe a bunch of grease is better?
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Molto Verboso
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With the cover off, you should be able to see where it's rubbing and since it's metal-on-metal, a bit of grease would probably do the trick.
I am not sure if bushing the spring changes the rate or just limits the travel. I suspect the latter.
Maybe someone's got an original that they swapped out for that fancy version...

add: I know there are progressive or variable-rate springs. If that's what's on there, pre-loading will help but will also limit travel which isn't really an issue I guess.
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A firm bounce on the front should confirm that it has oil. If it bounces like a pogo stick then it's no good. If it damps out after one rebound then it's fine.

I suspect the shock is fine, it's just that dive under braking is just the way they are.
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oopsclunkthud wrote:
I suspect the shock is fine, it's just that dive under braking is just the way they are.
I think this sums things up quite well.
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