In the days of the Spacy weights were quoted dry, so every fluid was not counted in the weight.
Manufacturers could tell porkies and exaggerate about the weight because no-one ever drained all the fluids out.
This accounts for most if not all of the increase.

halfabusa wrote: So if the seat region of the frame was narrower, it would have weighed much less.

Not sure what you mean about narrower.

Imagine your arm and how it bends at the elbow, that is the open triangle like a scooter

Now weld a pole onto your shoulder and grab it with your hand and you have a triangulated frame, your elbow can't open and close anymore - that is like a rigid bike frame.

To make your free elbow as rigid as the triangulated one you have to stick a lot of something around your elbow and that is going to be heavy.

I agree it could be a lot better than it is and the R&D on scooters is going to be less because they just don't shift in the same numbers as bikes but the basic problem will always be there with the traditional scooter shape.

You can't get away from levers v triangles, no matter what material you chose, the bike version inherently stronger than the scooter version and can therefore afford to be lighter.

If people would accept other, more radical shapes things would really get interesting but that also means losing the advantage of a high viewpoint.

The basic problem is that if you keep the same design, the way to lose weight is to use lighter materials. That means you either add to the cost (lighter materials of the same or better quality are more expensive) or lose quality because the lighter materials are less strong and/or safe.

How about designing a Burger not meant to carry a pillion?

I think that the ideal Max-scoot chassis could be a pressed steel monocoque exoskeleton.
Not exactly a new idea though.

halfabusa wrote:

Bluebottle wrote:Surely weight gets added because of a straightforward engineering problem:
A bke has structural frame members running from the seat base to the headstock (bars). these triangulate the frame and make it rigid.

On a scooter the triangle is open on one side because the top members are missing, that is a weaker shape so the 2 existing sides get beefed up to acheive the rigidity. The extra metal makes the whole thing heavier.

So if the seat region of the frame was narrower, it would have weighed much less. Such a shame, as with the technology being where it is, i doubt it's rocket science to design a frame that would be more rigid, therefore requiring less amount of beefing up.

As Irev said, the fairings could be improved with lighter components used in the manufacturing but the end price would then take a big hit as we already have a TGS in the market and i dread to think how much a rigid framed scooter with carbon fibre fairings would cost... 15 grand?? Now that would open up a hell of a topic here.

*****15 grand?? Now that would open up a hell of a topic here*****

I would buy one and a BMW TGS just to p155 off GN2

Just saying..

halfabusa wrote:i dread to think how much a rigid framed scooter with carbon fibre fairings would cost... 15 grand?? Now that would open up a hell of a topic here.

It sure would. 20+ and not even half the scooter would be made from carbon fibre.

There is simply a lot of material used on a scooter except the engine.


TA-pa-TA-pa-taPAtalk

kayz1 wrote:I would buy one and a BMW TGS just to p155 off GN2

Just saying..

If you're struggling to raise funds for those purchases, I would be happy to help out and make you an offer for your R90S...

Bluebottle wrote: Not sure what you mean about narrower.

I thought you meant both had triangular frames, with the scooters' exception being the top of the triangle at the seat point was wider and that was the reason for weakness.

Now you explained with the welded arm example (sounds like a nice horror movie plot) i understand better.

Its an inherent design feature that they are doomed to be so heavy then. In that case i can only think of improvements moving the engine performances higher with more hp to accomodate the weight. Unfortunately majority of brands think that more hp can only be obtained by bigger engine, but what they don't care about is bigger engine brings even bigger weight.

peugeot seem to be the only manufacturer that is trying it in a clever way by experimenting with superchargers (unless another brand has done something more clever i don't know about) and i wish them good luck with their ambitions because if they can harness some more power from tiny scooter engines without comprimising their lifetime or weight, then we could one day be riding on reasonably small scooter engines which have enough power to make us all happy.

It's not like i'm after crazy power either, 20%-25% improvement over any given scooter would be enough i think.

halfabusa wrote:Its an inherent design feature that they are doomed to be so heavy then.

Nope, it's not.
Huge weight reductions could be made by changing (and improving) the design.

Yes it is doomed to always be heavier than a bike of the same material or technique.

They could be lighter than they are now, what that does to the cost is another matter