Ducati Sporting Club UK > Model Specific - Discussion, Technical Problems and Help > General Motorcycles only > painting marchesinis??

[Nattyboy]

Originally Posted by loony888

are the marchesini's alloy or magnesium?
if they are alloy, fine, paint or powder coat, either is an option.
if they are magnesium, be aware, they have a zinc di-chromate coating that protects the magnesium from moisture absorption from the atmosphere, this causes corrosion and makes the material weak and brittle, NOT GOOD! if they are mag, don't get them blasted unless you know you can get the zinc di-chromate plating re done. when getting them painted i would reccomend asking for a dry rub with a scotchbrite pad and painted wet on wet. the finish won't be as perfect as a proper wet rub and sanding between coats but it will ensure the coating stays sealed and intact.
powdercoating magnesium doesn't in itself cause problems but again, they will want to blast them first and there goes the zinc di-chromate coating, another issue is the thickness of the powder, it makes it very difficult to see corrosion taking hold underneath, often looks like crazy trails lifting under the surface, if you see this on wheels you are thinking of buying, run a mile...quickly.
hope it helps,
cheers,
paul.

Blimey Paul - your worrying me now !! Ive got a brand new set of 5 spoke mags on my 888, and the front has got a few thin 'scribble like' lines on it which I put down to either poor paint, or brake fluid spillage (you may recall my brembo billets had a hairline fracture in them)...?

Nat

[loony888]

without seeing them it would be hard for me to say, but, brake fluid stain is on top of the paint, and obviously so, if the scribble like lines are UNDER the paint get em looked at. they are very thin lines that look a lot like crows feet. you say brand new, were they old stock? did you get them painted? to be sure, you should find someone who KNOWS what they're on about to have a look, get someone honest, not someone who will just tell you what you want to hear.
i don't mean to worry anybody but it's worth remembering magnesium wheels are primarily for race use, smooth roads, frequent inspections etc, and i know what i'm talking about from experience, i've been running 2 piece marvic superlight wheels on my 888 and other bikes for years. catch them early enough and you can re-plate them and all is well.
cheers,
paul.

[Nattyboy]

Originally Posted by loony888

without seeing them it would be hard for me to say, but, brake fluid stain is on top of the paint, and obviously so, if the scribble like lines are UNDER the paint get em looked at. they are very thin lines that look a lot like crows feet. you say brand new, were they old stock? did you get them painted? to be sure, you should find someone who KNOWS what they're on about to have a look, get someone honest, not someone who will just tell you what you want to hear.
i don't mean to worry anybody but it's worth remembering magnesium wheels are primarily for race use, smooth roads, frequent inspections etc, and i know what i'm talking about from experience, i've been running 2 piece marvic superlight wheels on my 888 and other bikes for years. catch them early enough and you can re-plate them and all is well.
cheers,
paul.

Yes - they were old stock. Had a look tonight. Rear - no problem.

But the front has these liitle 'worm type' marks here and there and now im worried - these wheels have only been on the bike a year and ive probably covered less than 1000 miles.

Ive attached a couplf of pics and close up it looks worse than it is - opinions appreciated..!

Nat

[Nattyboy]

another

[loony888]

yeah. that looks exactly like the lines on my marvics! my problem arised from a painter wet rubbing my wheels for paint and inadvertantly rubbing through the zinc di-chromate. neither the painter or myself knew the problems associated with his actions, but, i found a place that re plated my wheels and armed with the knowledge to know what can and can't be done i have had no problems since. 5 years and counting. for your sake (and the sake of your wallet) don't let them go too far, get them re-plated, re painted and ride it. i saw a 916 at a national rally here in 2000 that had those marks EVERYWHERE on both front and rear wheels, i tried to tell him how dangerous it was but he wasn't interested. glad i wasn't riding it, that's all i can say.
cheers,
paul.

[Iconic944ss]

As an aside - I was always led to believe Dymag were the peeps to contact wrt wheels manufactured by anyone, if there was any doubts about deterioration etc as they could not only x-ray / dyepen test them as necessary but advise on refurbishment.

I never did get around to contacting them about costs - but - the best don't come cheap I guess!

Cheers - Frank