SS90 (copy) bodywork preparation etc

Anything related to paint & bodywork issues on scooters....
Knowledge
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Hi,

Back in 2011 I bought a very cut-down Spanish 125 frame from one of the members of this forum (with a V5) with the intention of preparing an SS90 copy for my son who was, at that time, studying chemistry at York. The plan was to have the scooter ready for his graduation. He has since graduated, worked for a couple of years, taken a teaching degree, graduated from that, and still hasn't got the scooter.

Here is the story, as lifted from my original posts on the smallframe forum. There is a happy ending.

I hope you like the story and learn a bit along the way.
Martin
Knowledge
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8 Nov 2011
Thanks to Soosh, I have a small-frame and log-book. My plan is to build an SS90 copy and fit an existing PK motor into the chassis.

Now have a look at the photo, as see what a task I have ahead of me.
Image
Never mind, I weld and I know a few good people, but I will still need your help.

Has anyone got a back-end available?

Whilst I know you can obtain some new panels (the engine side rear panel is available from WSP and some German shops), I haven't seen the LHS for sale. This might need some careful fabrication.

Lots more questions to ask, but the rear-end shortfall seems a good place to start.

Thanking you in anticipation.
Martin
Knowledge
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9 Nov 2011
OK, I've ordered a new engine-side repair panel from Germany (£56 inc postage, which is nice), but if anyone has a panel for the other side, please let me know. I don't suppose there is a fibre-glass version for sale?

My next thoughts turn to the floor.

I have purchased an SS90 floor from one of the members of this forum and offered this up to the Spanish frame. As expected, the floor is an inch (or so) too short.

Image

OK, so I can cut away the original floor, but if I do not shorten the frame to suit, the spare wheel will not sit right.

Image

Note the gap in front of the wheel on my frame, and that on Mr Collier's original.

Image

Someone must have modified a smallie frame into a shortie frame. Can anyone explain how it is done?

Ta

(Not many answers were forthcoming, but I couldn't stop now)
Martin
Knowledge
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9 Nov 2011
Thanks GP200. That is an interesting insight into the conversion, and thanks for the photos.

As you can see on my machine, the gap at point A is noticeable.

Image

but point B is correct when I compare it to Mr Collier's machine.

On your machine GP200 (a member of the smallframe forum), does the wheel sit correctly at point A (it appears to) but is there a gap at point B? Looking at your machine, this looks an acceptable compromise.
Martin
Knowledge
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9 Nov 2011
Thanks for the replies guys.

I have been searching for a short-wheelbase frame for some time, and I can't find one. I chatted with Sam at TSR in the Far East. He had a ready supply of 50N frames, but these have dried-up. When people do offer him one, they want top dollar and it is barely a viable option for Sam, let alone me.

Vespa prices in Italy and German are mad at the moment. It is close to the tipping point where we will be exporting Vespas back to Italy, whatever Belisconi might have planned.

Since I wrote the post earlier tonight, I have watched the Frozen Planet (no inspiration there, but nice photography) and come up with a plan.

First I find two square sections of box steel, where one slips nicely through the other. Now weld one end on the horn of the seat, and the other onto the inside of the steering column (like a bar for a motorcycle petrol tank), making a slip-joint. The line of this arrangement needs to be parallel to the floor.
Image
Next, remove the old floor panel, sympathetic to the new SS floor pan. Part cut though the tunnel behind the foot-brake and tack-weld the new floor pan in position.

Now cut the tunnel through and slide the front section off the slip-joint box-section. Trim the tunnel at the front and then cut a vertical slit in it so it can be widened (stretched) to match the other section of the tunnel, and then inserting a thin triangle of steel.
Image
Now re-engage the slip joint and use this to line-up the two detached parts of the frame and go for the final welds.

The secret here would be offsetting the two principle welds: the one across the floor, and the one across the tunnel, in order to preserve the strength of the monocoque chassis. The triangle inserted in the front of the tunnel should be hidden in the spare wheel.

I acknowledge that this process has some inherent dangers, but I intend that the frame would be put through the jig to correct any wonkiness even if I didn't do this alteration.

Is this a plan?
Martin
Knowledge
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10 Nov 2011
Now I need to find an SS90 to measure-up, and enough space to make-up some kind of jig.
Knowledge
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12 Nov 2011
The frame is definitely going SS90 route now, but the photos you have provided are useful as I have little knowledge of small frames and need all the help I can get. I also happily acknowledge that the Spanish can make better scooters than the Italians. I sight the Spanish Lambretta as a superior version to the Innocenti machine, with better welding and more strengtheners. If MotorVespa put as much effort into their frames as Servetta, then the strengtheners shown in your photo will be useful.
Knowledge
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15 Nov 2011
Not all the parts are re-produced. The left hand side panel isn't made and some of the other parts are quite expensive; so much so that you feel that that buying them in just to cut them up is a bit of a waste (well not a waste, but an expensive risk).

I need a measurement too. I want to know the distance from the horn of the seat to the point on the inside of the legshields, parallel with the floor (on the centre line) for an SS90. This is effectively the line of the underside of the dummy tank.

Can you pop out and measure the red one for me Tony (O'Brien)?
Knowledge
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16 Nov 2011
Tony, that's a pretty neat idea; using the front and back mounts for the seat as a mount for the bracket that will keep the frame straight during the shortening process.

I am still thinking that my sliding-brace idea is still the way to go, but I have revised my idea for narrowing the centre tunnel. Whilst I thought of cutting a V into the front of the tunnel to widen it (as it turns up the legshields), I now think it would be better to cut a V into the horizontal (top) of the tunnel and narrow it.

This will help maintain the line where the flange on the bottom of the tunnel meets the floor pan.

Anyway, I should have the final piece of the jigsaw this weekend. I will then have the Spanish frame, the repro floor pan, a brand new RHS of the back end and a rather tired full back-end from a V50.

Then, and only then, will the angle grinder be fired up to prep the parts.
Knowledge
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23 Nov 2011
An update. Tonight I started the conversion.

Taking my previous idea, and the suggestion from Tony, I obtained two box-sections of steel and mounted them on a bolt-on fixing where the seat attaches. This is parallel to the floor.

Image

Image

The Allen bolts A and B are drilled and tapped at 45 degrees to take up the slop between the two box sections. Inserting them at 45 degrees ensures the internal box is always pushed into the same corner. Continuity is important if the two halves are to be reconnected straight.

Image

The bracket is high enough to allow the spare to sit-in the frame. Whilst the wheel is not the critical measurement here, it does represent the look I am after by closing up the centre section of the frame.

Image

The bolt on bracket is much better than my idea, as the half the bracket can be unbolted to allow the two halves to be fully separated and re-built with greater flexibility. Nice.
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