More Ducati Fever?

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Might pick this up for a couple grand...

You guys here have been more helpful than the Ducati forums.

Are these good or bad? I've read that they are not bad. Cagiva instilled some good QA.
 

grandpaul

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Sure looks like a direct attack on the Honda Interceptor, circa '83...
 
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Hi Dave,
650 Cagiva, same engine as the 650 Ducati Pantah (red and yellow), the last of the Pantahs before the 750 F1 series.
Fit 88mm cylinders and pistons and you have a 750. They fit straight on.
These are now sort after for anyone building a TT replica as they were one of the last Ducati engines with rear facing carbs on the rear head. They had smaller lift cams than the F1's and the Pantahs, but any of the later cams (up to the 800 and 1000s ) can be used but you will have to use 2 front cams as the bikes after F1 had forward facing rear carbs and the rear cam is ground to spin wrong for the earlier rear heads.
They are a nice thing to ride and are getting up in price.
All these have their electronic pickups boiled in oil similar to the bevel twins so watch for bad wiring insulation in the left case.
Graeme
 
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See Ed Milich's cagiva bimota site for Ed's Cagiva 650 racing info, and exploits.
They are very robust engines, keep the belts regularly renewed and don't tighten them too much.
6mm slack is about correct. Too tight and the cam bearings suffer, too loose and cam timing suffers.
No other weak or suspect issues.
They started out on Dr. Eng. Taglioni's drawing board in 1974 as the 500 Pantah.
Way ahead of their time.
 
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GRM 450 said:
Hi Dave,
650 Cagiva, same engine as the 650 Ducati Pantah (red and yellow), the last of the Pantahs before the 750 F1 series.
Fit 88mm cylinders and pistons and you have a 750. They fit straight on.
These are now sort after for anyone building a TT replica as they were one of the last Ducati engines with rear facing carbs on the rear head. They had smaller lift cams than the F1's and the Pantahs, but any of the later cams (up to the 800 and 1000s ) can be used but you will have to use 2 front cams as the bikes after F1 had forward facing rear carbs and the rear cam is ground to spin wrong for the earlier rear heads.
They are a nice thing to ride and are getting up in price.
All these have their electronic pickups boiled in oil similar to the bevel twins so watch for bad wiring insulation in the left case.
Graeme
Not much interested in hopping it up. Just want to make sure it goes.

Anything else to look out for?
 
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No, they are tough.
Look around the drive sprocket for chain damage, there is an oil gallery that can be damaged just inboard of the sprocket. If it's thrown a chain the case there can get damaged.
The sprocket is held by a tab with 2 x 6mm bolts and can feel loose on the splined shaft, this is normal.
The swing arm is held by a steel axle that goes through the cases, runs in bronze bushes with oil seals at each outer end of the cases. The bushes are lubricated by the engine oil.
The Bosch ignition is pretty reliable but is getting old now.
Electrics (switch gear) are Nippon Denso from Japan, same or similar to period Suzuki.
Suspension is Marzocchi or Paoli, all rebuildable.
Brakes are Brembo, again rebuildable.
Some had a vacuum fuel tap that can make starting hard, if so they can be replaced with Paoli standard taps.
Frames are very strong.
Steering head bearings are tapered roller.
Cam belts are the only thing apart from the usual service items that need attention.
They are desmo so the heads will need to be removed to reseat the valves and adjust the valve clearances.
There's no head gasket, just O rings for the oil gallery's to the head. There is a cylinder base gasket.
They don't require torquing, like a Norton. They are similar but stronger than your bevel, but have plain bearing big ends and belt instead of bevel drive to the cams.
Carbs are 36mm Dellorto pumpers (maybe smaller on Ally's?)
Get a manual from bevel heaven web site.
Graeme
 
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Just looked at your picture and saw it has a hydraulic clutch.
Keep the fluid changed and clean regularly or you will be rebuilding the slave cylinder, easy but painfull.
 
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GRM 450 said:
They are desmo so the heads will need to be removed to reseat the valves and adjust the valve clearances.
Graeme
That sound like fun. :shock:
 
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It's not rocket science, any competant person can do it. It helps if you have a good assortment of shims.
Same size as your 860 too, you just need some closers for this one.
 
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GRM 450 said:
It's not rocket science, any competant person can do it. It helps if you have a good assortment of shims.
Same size as your 860 too, you just need some closers for this one.
Reading through the workshop manual they don't specifically cover adjustment, more just disassembly. The Pantah Workshop Manual was slightly better.

As a side note when we were at Barber last year we checked out the Ducati paddock (they had a standalone show area) and one vendor was selling some trick valve adjustment stuff. I remember giggling at the a) cost and b) reasoning why any sane person would put up with such a maintenance nightmare. :mrgreen:
 
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swoosdave wrote,

"As a side note when we were at Barber last year we checked out the Ducati paddock (they had a standalone show area) and one vendor was selling some trick valve adjustment stuff. I remember giggling at the a) cost and b) reasoning why any sane person would put up with such a maintenance nightmare."

I own a Commando too, so I know about the maintenance involved with them too. (ones that get used regularly)
There's not that much difference.
If you shim the valves properly they are good for 20k kms before they need looking at.
The desmo maintenance nightmare is a myth.
I have 4 desmos and 1 norton, guess which one gets the most attention?
The 2 belt desmos are the least attention seekers.
If you do buy it and need assistance I would be happy to help.
Graeme
 
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GRM 450 said:
swoosdave wrote,

"As a side note when we were at Barber last year we checked out the Ducati paddock (they had a standalone show area) and one vendor was selling some trick valve adjustment stuff. I remember giggling at the a) cost and b) reasoning why any sane person would put up with such a maintenance nightmare."

I own a Commando too, so I know about the maintenance involved with them too. (ones that get used regularly)
There's not that much difference.
If you shim the valves properly they are good for 20k kms before they need looking at.
The desmo maintenance nightmare is a myth.
I have 4 desmos and 1 norton, guess which one gets the most attention?
The 2 belt desmos are the least attention seekers.
If you do buy it and need assistance I would be happy to help.
Graeme
I heard that the factory recommended 6000 km for the Pantahs. The workshop manual said to check it every 1500 km. Obviously in Oregon it's hard to put on 6k miles on any bike if you want to stay dry.

There are, ahem, quite a few Ducatis in the local Norton club (for once more Ducatis than BMWs) and so there are plenty of folks to help. Thanks for the offer!
 

gtsun

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Your making me real jealouse Swoosh!! I'm surprised at how soft the market is on Ducks these days. Several friends have bought realy nice 750 ss and sim that are fairly low miles for around $2,500 to $3000. Then again Im being forced to sell some vintage guitars & equipment & the prices on them is down pretty far too.
 
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"Want to stay dry" - do the cam belts slip timing if they get wet? [if you ride without the cam belt enclosures road debris can fly up & catch twixt belt & gear with nasty consequences].
 
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GRM 450 said:
They are desmo so the heads will need to be removed to reseat the valves and adjust the valve clearances.
Graeme
Are you sure about removing the heads? I believe on these you do have to pull the rocker spindles (you can have them modded to slide over like the later bikes) to get to the shims but is pulling the head the only way?
 
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You will have to take the heads off to seat the valves if needed, same as any head.
You can shim them by removing the belts, rocker covers, and the l/h cam bearing covers then pull out the opening rocker pin.
The opening rocker will then fall free and can be removed.
And so will all the end float clearance shims.
Then you can push the closer shim down and remove the collets and remove the closing shim.

Way too hard to do it this way.
And too hard to measure accurately .

Much easier to do the shims on the kitchen table or good bench with the heads off.

You'd have to have the end of the opening rocker shaft machined off and buy 2 spring clips from the later models to make them easier to do without removing the rocker pins and belts and cam bearing cap.

Can be done easy and makes any shim changing possible without removing the heads.
 
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Want pictures?

Also you must line up the timing marks on both cam pulleys on both heads with the marks on the rubber pieces that the top of the belt covers screw to,,,

And the bottom belt pulley with the mark on the case.
Before you remove the belts, or heads.
 
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