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Here you'll find some info on Ducati repair and modifications along with photos. I've got stuff for sale too, so check out the older posts. Please leave comments about anything you see, good or bad. Thanks for looking, Steve

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Wednesday, April 18, 2007

HOLDING THE PULLEY

I use these curved jaw Vise Grip pliers with an old belt to hold the pulley while removing the nut with an 1/2" drive impact gun. The excess portion of the belt is wrapped under the handle of the pliers against the frame rail for support.

OFF SET KEY IMAGE



Here you can see the off set. The key can be inserted either way (to advance or retard the timing) so make sure it rotates the cam pulley CCW, advancing the cam timing.

OFF SET WOODRUFF KEY


I had to advance the V Intake cam eight degrees of crankshaft rotation.
This Ducati off set key marked with 4 dots moves the pulley either way (advance or retard) 4 degrees on the camshaft.
Because the camshafts spin at 1\2 crankshaft speed this 4 degree adjustment equals 8 degrees at the crankshaft.
Make sure to use a new nut.

Tuesday, April 17, 2007


Here the bent pointer sits nicely on the helper (note: the washer I decided to glue in place)
But, alas…the washer fell off, and then the tool slipped off the shim and got stuck down in the recesses of the head and took me 10 mins. to dig it out.
SO…I ended up just using the “old” method!
Oh well, can’t blame a guy for trying.



Here it is snapped onto the shim.












Tired of trying to keep the pointer of the dial indicator on the edge of the opening shim.
I made this neat little helper from a plastic “thingy” I found laying around.

The following is a follow up to my original Power Point presentation on Cam Timing that can be found here:
CHECKING CAM TIMING ON 4 VALVE DUCATI

Degree wheel set up on Crank turning Tool. NOTE: Pointer (red tip) set to TDC on degree wheel (yellow mark on wheel)

Dial indicator with flexible holder and homemade aluminum plates. (top)

Mounted up on the Horizontal cylinder Exhaust valve..(bottom)
Homemade pointer sitting on shim.


Horizontal Intake valve being checked.
Aluminum plate with flexible support checking H. intake

Sheet to keep track of numbers.





Both closing shims installed.






















Here a rubber coated blade of a screwdriver is inserted behind the closing rocker arm holding it against the helper spring so that the shim can be installed.


A shim can be made smaller by up to 3 thousands of an inch by carefully sanding.
I take one thou off by sanding on a piece of tempered glass with 400 grit paper and WD40.
Followed with 600 grit.
More can be taken off by starting with 220 grit paper followed with the 400 then 600.
Make sure the shim is held flat and rotate it on the paper occasionally.

BE CAREFUL. THE SHIMS CAN GET VERY HOT WHILE SANDING.





Finish each sanding session with a good cleaning with brake cleaner and compressed air.
This also helps cool the shim before rechecking it.

Make sure the shim is cool, then check the thickness. Repeat the process until the correct thickness is obtained.




Shim ready to be installed.















Sometimes a burr will prevent the shim from sliding easily over the valve.

Carefully remove it with a carbide bit















.

I've included this image to show how I've labelled all the pieces. I use paint sticks in different colors and Sharpies, plastic bags and tags to mark the heads, cylinders, camshafts, covers, etc. I note the RIGHT and LEFT sides and have a series of dash marks for the corresponding locations on reassembly. I also separate the two cylinders and heads and all the pieces so that I can't mix them up.
When most of the engine is disassembled like this it can get confusing with parts all over. But when everything is properly labelled it's like putting together a Ducati puzzle.

Write everything down.
I measure in "inches" because it's easier to do the math. But I convert the readings to "mm" to determine the correct shims to get. It's important to take "your" micrometer with you to check the new shims before purchase as they may be labelled incorrectly or checked with a different device.

My feeler gauge setup makes life easier.

The top of the shim should be flush with the top of the valve. (R)

You may have to pull up on the bottom of the rocker or snap it a couple of times against the closing spring. This will seat the closing shim.


It’s critical that the keepers are seated correctly!

Installing the half rings, or keepers. A little grease holds them to the screwdriver.

It’s a plastic spacer made from a garden hose fitting, metric stud, nut and a couple of washers.
It works great. I like to use a 10mm flex-head ratchet wrench on it.

Here’s my homemade rocker shaft removal tool installed, ready to pull the rocker shaft.

Keep all the valve train pieces organized.
Makes it much easier on reassembly.

Sunday, April 15, 2007



RANDOM NOTES
Here’s my universal opening shim
Tool and digital micrometer.
The 1mm feeler gauge attached to a block of wood makes life easier.




RANDOM NOTES
Here’s my universal opening shim
Tool and digital micrometer.
The 1mm feeler gauge attached to a block of wood makes life easier.


Valves are “lapped” back in.


All valves are removed and cleaned along with piston crown and combustion chamber.



I set up my table with wood head support and feeler gauges.



I find it easier to check valves with heads removed.


Top rocker is stock, bottom is a reconditioned one.

Top rocker is stock, bottom is a reconditioned one.

On the right is a rocker arm reconditioned by Guy Martin at MBP. Note the longer filled and resurfaced area.

My 1998 748 didn’t have an oil feed hole in the front (Horizontal) cylinder crankcase. I understand some models may have one.
These passages are for air cooled models that don’t have external oil lines like the SBK’s.


Here a 4mm set screw is inserted into the oil feed hole in the Vertical cylinder crankcase.
Use red loctite. This eliminates a potential oil leak at the base gasket. I filled the recessed area with 1411 Three Bond
Sealant and eliminated the green oil ring.

Nice clean piston ready for rings...

Work in a clean, organized environment


Fit each ring in bore and check the end gap


CLEANING PISTONS
FITTING NEW RINGS




S
Wax can also be used in the combustion chamber. WD40 applied to piston crown to prevent sticking to wax.
Adjustment is made with base and head gaskets to obtain 1mm of clearance.


Note lines in chamber where head gasket sits. Squish area is just inside gasket in flat area before the chamber tapers down toward the valves.

Measurements can be taken with a micrometer or vernier calipers. Here, the solder thickness, after piston compression, is checked.


CHECKING SQUISH---DUCATI 748
1MM Solder is positioned in the squish area of the combustion chamber with Play Dough.
CHECKING "SQUISH"

Special wax in varying thicknesses can be used on the piston crown.