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Discussion Starter · #1 ·
Started pulling my new 748 to bits to overhaul it. The belts were well and truly knackered and are now off and marked up ready for when the new ones arrive. I've stripped all the stuff off the engine with a view to dropping it out to get good access to the valves. So far I've checked the vertical cylinder clearances to get an idea how things are. Was a bit surprised to see that all clearances are on the tight side. The 3 of the closes are less than 0.05mm but the closer shims rotate and there is no drag on the cams. All the openers are around 0.05mm tighter than recommended. My gut feeling says that they have been set that way deliberately.

I remember reading somewhere a while ago that some mechanics had been setting the closers tight to get a better behaved bike at low speeds. Is this so? Otherwise I will pull the cam gear to bits and get shiming!

Apart from the valves the biggest hitch I've come across so far is a ding in the front wheel. Luckily the bike came with a spare set. I would like to see if I can straighten the dent, it is failry long and shallow so it should be possible. It's going to be a fun winter.
 

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Years ago when I was new to Ducati my dealer, Eximport cycles, told me the opener gaps were .5mm all around. Next valve change I had 7 bad opening rockers but the bike ran very well.
 

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Started pulling my new 748 to bits to overhaul it. The belts were well and truly knackered and are now off and marked up ready for when the new ones arrive. I've stripped all the stuff off the engine with a view to dropping it out to get good access to the valves. So far I've checked the vertical cylinder clearances to get an idea how things are. Was a bit surprised to see that all clearances are on the tight side. The 3 of the closes are less than 0.05mm but the closer shims rotate and there is no drag on the cams. All the openers are around 0.05mm tighter than recommended. My gut feeling says that they have been set that way deliberately.

I remember reading somewhere a while ago that some mechanics had been setting the closers tight to get a better behaved bike at low speeds. Is this so? Otherwise I will pull the cam gear to bits and get shiming!

Apart from the valves the biggest hitch I've come across so far is a ding in the front wheel. Luckily the bike came with a spare set. I would like to see if I can straighten the dent, it is failry long and shallow so it should be possible. It's going to be a fun winter.
On my 848 race bike we set the closers at 0.00 mm and the openers at 0.127 mm. Runs just fine :D
 

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Heads on the bench AND have a full shim kit at your disposal... Setting to 0 but having to run back and forth to the dealer for shims would not be fun. I usually have to re set a few clearances during a normal adjustment.
 

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Heads on the bench AND have a full shim kit at your disposal... Setting to 0 but having to run back and forth to the dealer for shims would not be fun. I usually have to re set a few clearances during a normal adjustment.
Spot on, and be prepared to have your fingertips a bit shorter from the sanding... :)
In education purpose its good to go through it though, much like military service and assembling the rifle, you can do it blind folded after.

Magnet pen and sticky grease saves time.
A big round-shafted screw driver, to yank the closing rocker and seat the half rings properly, a 30cm soft metal pipe(copper/alu) to get them lose in case they get stuck, helps too. Disclaimer, this is not what ducati says lol, totally works though.

To get the rocker arms out I use a glide hammer and a 6mm bolt.
 

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Discussion Starter · #7 ·
Thank you gentlemen , just what I needed to hear. Have one closer out at 0.35mm+.
 
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