Skorpion 660 Lightweight Build

[droy]

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[breakwellmz]

I wonder how the weight of Mastiff/Baghira spoked wheels compares, would they fit?

[Puffs]

I didn't have that shim under the other tire, so I expect that is a bit lower than it actually is.

That depends on how high the centre of gravity is, the F/R weight distribution, the height of the scale & the wheelbase. For a 40/60 weight distribution, a centre of gravity at a height of 40% of the wheelbase (using 142cm for the Skorpion), and a 3cm high scale, you underestimate the weight by 1.7%.

Of course the fuel level makes a lot of difference too. And the tyres, both type/make & size, with a 180/55-17" weighing close to 5kg.

[jpmsteadi]

Makes perfect sense. A lot of wheel options there. I ended up buying a rear wheel from a 2018-2020 Kawasaki ninja 400 to adapt to the rear. It seems that with modern manufacturing even the stock wheels off of lightweight bikes are lighter than the options from the 90s that I can still find. I will be sure to measure, weigh, and post everything!

[Puffs]

I wonder how the weight of Mastiff/Baghira spoked wheels compares, would they fit?

Obviously I wouldn't know if those would fit, but fitting a tube in a spoked wheel has disadvantages. I just measured a 110/90-17" tube at 0.671kg, I'd guess a 160/60-17" would be around 0.75kg.

In addition to the pure weight, another problem there is that all that weight is more or less at the outside of the wheel, effectively adding to the wheel's rotational inertia (I=mr²). That will make the bike feel more 'stable', but particularly at higher speeds, it will also be more difficult to change direction. For that reason too it pays to use the smallest & lightest acceptable tyres & rims fitting that. (I just mentioned a 180/55 earlier because I saw that in droy's sheet.)

An advantage of spoked wheels is that they are more resilient, and that a catastrophic breakdown (see https://www.youtube.com/watch?v=3oFaoBiuhko to get the picture) just does not happen - there are always ample warnings.

[breakwellmz]

You can go tubeless with spoked wheels i`ve considered doing it myself.

[Puffs]

Go for it, and please let us know how you fare!

[Puffs]

Some links on this:
https://www.bartfactory.com/products/ba ... n/?lang=en
https://www.advpulse.com/adv-products/c ... ed-wheels/
https://www.youtube.com/watch?v=JPzoqi_4X7o

[breakwellmz]

Familiar with all those links and more thanks Puffs.

[Puffs]

Good, I adapted my text a bit.
Using a tube is currently still the most common approach, I'd guess.

[breakwellmz]

The Mastiff has the advantage that the rim profile is suitable for tubeless tyres which not all spoked rims are.

[Puffs]

Yes, the rim profile could be an issue (seating bead? why is the Mastiff's rim so suitable?), and also the surface/finish of the rim. For instance the alu rim in my 251 would seal poorly, even if I sealed all the nipple holes perfectly: the surface is quite rough and the tyre wouldn't seal properly on it. And with steel rims you often have corrosion (which may also ruin the seal in alu rims). And what about tire clamps & the 10-12psi I run my YZ at, and how about re-tensioning spokes, as you need to after a while, ...

Anyway, there'll be a solution for everything, but I'd say there's a reason why all modern road race bikes use cast wheels, and all dirt race bikes use spoked wheels. And light tyres / low rotational inertia is desirable for speed.

Maybe weigh your wheels @ next tyre change? But comparison may not be straightforward & the devil is in the detail. For instance the 5.50"x17" of my Ducati weighs 4.2kg, but the construction is quite different (no sprocket, no disk, no bearings on wheel).

[jpmsteadi]

I have been doing some cosmetic stuff the last couple of days. Been stripping the paint off the tank and wet sanding it. I think the natural plastic is going to look great. Also, drained of fuel this tank is SO light. Its fantastic. And made by Acerbis actually.

[Puffs]

... and you can more easily see how much fuel you have.

Over the years Acerbis made a name for quality. But avoid parking it out in the sunshine, as UV oxidises plastics.

[jpmsteadi]

... and you can more easily see how much fuel you have.

Over the years Acerbis made a name for quality. But avoid parking it out in the sunshine, as UV oxidises plastics.

Yup! I got really used to being able to see how much fuel is in my DR650 with the natural plastic tank. And all my bikes live in the garage. If it does yellow some in the sun can just restore it again (to a certain extent)