Fancy lightweight wheels

[IanB]

Have a set of BST wheels on my R1 and it has made a noticeable difference, very much when I put the standard wheels back in when I shagged the tyres and the standard wheels had a new set on them, could wait to get the BSTs' back on.

Have you got a photo without the bike so I can see the 944?

[demographic]

As I understand it you can have lighter springs with lighter wheels making for a softer ride.
With heavy wheels you need stronger springs to get the rebound fast enough so the wheels arent skipping over dips and keep in contact with the road.

With changes to the damping rates needed as well.

Loads about this in John Robinsons Chassis Tuning book.

[Skub]

JR was a cool dude.

[demographic]

JR was a cool dude.

Aye, I never missed an issue of PB for a few years. Til it went all lad mag and started getting on my nerves. Also getting rid of the readers specials kind of killed it for me.
I might not like every one of the specials that Weeksy has been putting the effort in to post about recently but I do appreciate that I get to see em.

[crust]

?

I've got a set of Marchesini wheels on my Ducati 900SS project. Compared to the standard 3 spoke wheels they save a ridiculous amount of weight at each end.

Standard wheels



5 Spoke Marchesini wheels (got them from Rich at Louigi Moto, only been used for practice laps on their TT2 Ducati)



Some day I'll ride the fucking thing, but having ridden Dukes with these different rims, I'm sold that they turn / flick so much more easily than the standard rims.

The UKMOC boys have advised not bothering with tuning my monster but get lighter wheels instead. Any idea how much weight the Marchesinis save?

[KungFooBob]

In DD racing you can only use wheels originally fitted to Monsters and SS 600/620's.

People with the older wheels (like GP's first picture) often replace them with the newer IE wheels to save a bit of weight.



You're not allowed to use the 5 spoke ST wheels like GP's 2nd picture.

[Potter]

... I'm told that they turn / flick so much more easily than the standard rims.

The difference in weight between my standard LC wheels and the ones I have now is massive. If you hold the standard wheels in your hands it's like being at the gym, they're really heavy.

With the lighter wheels in it does feel very flickable and in racing I can see why it's better. On the road it does feel a lot lighter, it makes a difference to acceleration as well, so I think overall I prefer the lighter wheels. But it's more of a change of characteristic rather than something that makes the bike so much better, at least on my old LC anyway.

A good way to compare it is the difference in having a lightened or heavy fly wheel.
You can definitely feel a difference, and many would say it's better, but you seem to lose some momentum and the bike feels less substantial, if that makes sense.

[G.P]

The UKMOC boys have advised not bothering with tuning my monster but get lighter wheels instead. Any idea how much weight the Marchesinis save?

There's lots of stuff on the Ducati for forum but some weights listed are with cush drives and sprocket carriers fitting and some without so its difficult to tel. also they are not identified at part number level. Anyway, I reckon over a kilo at the front and nearer 2 at the back. I remember comparing them before fitting and it was significant if non scientific.
You can also lose more weight with the front discs over standard. on mine I also lost the speedo drive and cable too as the ST4S has a different axle diameter.
Tuning is ok if you have to do a rebuild but Hi Comp pistons or a 944 conversion is spendy. FCRs are really hard to come by now and over £700 2nd hand. Rich at Louigi reckons Dellorto 39mm carbs are the way to go.

[crust]

Thanks, John, 3ish Kg hmmm

I've got FCRs on it already, bought a spare set of barrels and some 944 pistons years ago, just need to get them bored and plated.

Need to go back to work very soon, ebay has not been kind to my wallet - watch this space, erm no, watch my rustorection thread for updates when its warm enough to spend some time in garage

[mangocrazy]

... I'm told that they turn / flick so much more easily than the standard rims.

The difference in weight between my standard LC wheels and the ones I have now is massive. If you hold the standard wheels in your hands it's like being at the gym, they're really heavy.

It's been nearly 30 years since I've had cause to remove the wheels from my old 350LC (it's been at the back of a garage for all that time) and couldn't believe how heavy the wheels were. A bare front front wheel (no discs, bearings or tyre) weighs more than a modern wheel with discs, bearings and tyre on.

What wheels have you got on your LC now?

[KungFooBob]

You think LC wheels are heavy, try lifting an Air cooled RD wheel.

They have 'Malleable Iron' written on them!

[G.P]

Thanks, John, 3ish Kg hmmm

I've got FCRs on it already, bought a spare set of barrels and some 944 pistons years ago, just need to get them bored and plated.

Need to go back to work very soon, ebay has not been kind to my wallet - watch this space, erm no, watch my rustorection thread for updates when its warm enough to spend some time in garage

SOunds like youve got he makings of an optimised perfomance package there

I really need to pull finger and get mine finished off.
Ultimately I'd like to stick a 1000 or 1100 DS motor in it with carbs, but seeing as I've done virtually bugger all on it in the last year or two, apart from change my mind about bodywork, I'll just get it going with the stock motor but it will be significantly lighter than standard.

[SSR Suspension]

Ive seen some carbon rims implode on track, scary.

[Bigjawa]

Lovely jubbly GP.

Nowhere near the difference Carbon wheels make apparently, but at least they probably won't shatter on the first pothole they meet

That's also a concern. A mate has the latest Beemer HP4 thingy and it's already had a rear wheel replaced after what looked suspiciously like a hairline crack. BMW says no,merely a mark in the lacquer....but they replaced it anyway.

I vividly remember the rear Marvic collapsing on Robert Dunlop's bike at the TT,then more cracks were found in other wheels after riders became interesting in checking.

In fairness I think tech has moved on greatly since then and for the price of the gear,you'd like to think durability is no longer a factor.

If my memory is right, Marvic made two different wheels, a road wheel and a wheel for racing on tracks, they said that for a road race, they should have used the road model and jumping Ballagh wrecked the wheel.

[Yorick]

Nowhere near the difference Carbon wheels make apparently, but at least they probably won't shatter on the first pothole they meet

That's also a concern. A mate has the latest Beemer HP4 thingy and it's already had a rear wheel replaced after what looked suspiciously like a hairline crack. BMW says no,merely a mark in the lacquer....but they replaced it anyway.

I vividly remember the rear Marvic collapsing on Robert Dunlop's bike at the TT,then more cracks were found in other wheels after riders became interesting in checking.

In fairness I think tech has moved on greatly since then and for the price of the gear,you'd like to think durability is no longer a factor.

If my memory is right, Marvic made two different wheels, a road wheel and a wheel for racing on tracks, they said that for a road race, they should have used the road model and jumping Ballagh wrecked the wheel.

IIRC they paid out about £300k in compo.

[Mr. Dazzle]

The only way to make stuff lighter is to either make it out of higher spec materials, or reduce the safety margins.
Racing stuff does both obviously, but they're running in very controlled circumstances.

Personally I'd have no qualms with carbon wheels, if done correctly. Its perfectly possible to make carbon wheels tougher than the stock ones. But then I would say that wouldn't I?

I would also say the wheels are one of the very hardest things to make properly in carbon.

[Bigjawa]

IIRC they paid out about £300k in compo.

I think they asked for 1.5 million and got 700k, either way it didn't go far after all the rehab bills were paid. Robert Dunlop had to sell the big old house he lived in before the accident.

[Yorick]

IIRC they paid out about £300k in compo.

I think they asked for 1.5 million and got 700k, either way it didn't go far after all the rehab bills were paid. Robert Dunlop had to sell the big old house he lived in before the accident.

I stand corrected. Thanks. I didn't know the full details.

But Sheene did get £300k for his Silverstone crash.