500SD Back on the road

If you need technical information or help with your parallel twin Ducati GTL 350/500 or Sport Desmo 350/500 engine - post your FAQs, comments & questions here.
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TassieDevil
Cucciolo - the Lil Pup
Posts: 9
Joined: Fri Oct 15, 2010 4:02 am
Location: Tasmania

500SD Back on the road

Post by TassieDevil »

Hi All,
Have now fixed up my 77 500 Sport Desmo to the point where it can be ridden. Have mainly cleaned/fixed what I had to (carbies, brakes, bearings, indicators etc) and replaced the ignition with an electronic one.

Not the most powerful bike I have ridden but lots of fun.

Now need to fix a bad oil leak from the front the of the head and have it registered. Looking to ride it over the summer and perhaps restore the paint to the original red over the winter.

Anyone with any tips on how to get the cams out and head off simply (have new head gasket on its way)?

Here is how it looks now.

Image

Image

Had to fix quite a bit of wiring that was burnt out/modified. Also put in relays for the ignition and headlight (have you seen how small the wiring is in the switchgear).

Image
regards

Gordon
Chris Bushell
Parallel Twin
Posts: 107
Joined: Wed Oct 22, 2008 9:26 am
Location: Sevenoaks UK
Contact:

Post by Chris Bushell »

Gordon,

Nice looking bike!

Ok to get the head off, you have to take the engine out of the frame. I have found it easier to support the engine on a wooden box and lift the rolling chassis off the engine. I am not certain of the exact weight of the engine but it is close to that of a bevel V-twin and just about at the limit of my strength to carry.

Take the cam end caps off and withdraw the rockers, cam should then pull out with a slight tug. Make sure that you have a hand in there to hold the centre sprocket or it will go down to the crankshaft and it is a bugger to get back up. Then undo the head bolts and give it a tug!

You will need to lift the barrels to re-set the cam tensioner, putting that lot back on is a 2 man job!

On mine, which I rebuilt 2 years ago I found it difficult to work out the correct size for the sealing O rings on the oil feed and return holes in the gasket. I didn't want them to small or fat, but have still got some misting round the front studs that the oil feed goes up. I have decided to live with it as it is a mamoth job to re-do.

Have you made sure that you have lock wired the pressure relief valve down by teh alternator, every parrallel twing we have been in that has just been finger tight - you have been warned!

If you need any more helpo droip me an e-mail to [email protected]

Chris
TassieDevil
Cucciolo - the Lil Pup
Posts: 9
Joined: Fri Oct 15, 2010 4:02 am
Location: Tasmania

Post by TassieDevil »

Hi Chris,

Thanks for the info - does not sound too bad. I suspect setting the timing up again will be the fun part and I'm not sure I understand the procedure for resetting the timing chain adjuster. Guess I'll just have to try it and see.

I must admit I was hoping not to disturb the barrels if I could get away with it - bugger.

I have not had the alternator cover off yet (and hope not to yet). If I do have it off I will ensure things are locked in place. I can see where it is in the manual pic.
regards

Gordon
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DesmoBro
Mariana
Posts: 28
Joined: Sat Feb 26, 2011 10:26 am
Location: Gardner Ma

Post by DesmoBro »

Does your Gas tank have some numbers on it under where it says made in italy????
TassieDevil
Cucciolo - the Lil Pup
Posts: 9
Joined: Fri Oct 15, 2010 4:02 am
Location: Tasmania

Post by TassieDevil »

Hi DemoBro,

I can't see any but it has been re-painted at least once in its lifetime and I'm going to paint it again some time soon.

What would they signify?

Gordon
regards

Gordon
User avatar
DesmoBro
Mariana
Posts: 28
Joined: Sat Feb 26, 2011 10:26 am
Location: Gardner Ma

Post by DesmoBro »

Well Supposedly they only made 2,130 of the SD500 and the Original Tanks had a number on the Sticker (from what i've heard)....I just can't find anyone with an original tank with the original numbered sticker....so i'm not sure if it's actually a real sticker on my bike since no one else has one
ducadini
860 GT / GTS
Posts: 296
Joined: Sat Jul 31, 2004 9:54 am
Location: Antwerpen

Post by ducadini »

I bought a SD from the first owner and it didn't have the #sticker on it.
Several others in the neighborhood at that time (78-79) but none had any
other numbers on it.
They ran a race series in Belgium and Italy, never saw them.

Don't forget to glue the sidepanels on the inside with Tec7 or similar, or they will selfdestruct due to vibs.

When pulling the head don't forget the 8mm allen at the back of the head.
Keep an eye on the primary gear and markings as this doubles as the timing gear for the chain.

The first gear jumping is mostly the bronze bush it runs on and the shimming on this side.
This gearbox was later used in the first (red) Pantah and there it went from the word go.
Better bushes were made, but VERY rare to find.

Several other issues but these are the most important.
grt
ducadini
TassieDevil : still need the elec diagram ? see pm
Nego i ricordi peggiori
Richiamo i migliori pensieri
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