Glass bead blasting

Finally everything was ready for glass bead blasting of the cylinder heads. My friend Julius works as a blacksmith, and has blasting cabinet at work that he kindly let me use.
We did some test on aluminium plates and found that we got a smoother surface if we reduced the air pressure to about 6 bars. Unfortunately that made the process slower and I needed about four hours to finish both heads and the clutch cover. Julius got really tired and fell asleep on a sofa in the office, but I wanted to finish the work really bad, so I kept on until I was finished.

I’m quite satisfied with the result. Hopefully the surface got smooth enough to not let too much dirt stuck on it, since I intend to leave it untreated.

Some parts arrive

This week I got some parts I have ordered. First was a new rear brake caliper bracket. The The original bracket was damaged in an incident where the previous owner lost the rear calliper and one quarter of the brake disc while driving. Luckily he survivied!
I have earlier written about the work of measuring and making a drawing of the bracket. As I never thought I was going to find a spare part, my intention was to have someone milling a new part for me from my drawing. However I got a tip from Christian Jaekel on the Bimota mailing list that a former German distributor of Bimota, Reinold Kraft, still had some parts in stock. I sent them an e-mail and bingo! The bracket was on their shelf. The transaction was smooth. They accepted credit card and I sent a fax with my card number. About one week later the part arrived in my mailbox.

The second part that arrived was a new closer rocker to replace the damaged one I mentioned earlier. A new rocker costs about €135 ($150) here in Sweden, but I got a new rocker on German Ebay for €78 inlcuding shipping.

Finishing the monocoque

In parallel to all the other work I’ve been repairing a damage on the right side of the monocoque (see picture). I had some trouble finding a touch up paint in the right white colour, but finally I find a touch up for household appliances (fridges etc) that was close enough to the original colour.

The screws for the tank cap were rusty and didn’t look very good. The screws where exchanged for stainless steel and some parts of the lock got new zinc plating.

The lens for the rear light had a crack when I bought the bike. There was no trouble getting a new one since it is also fitted on the Ducati 851/888. The Ducati part number is 52640021A.
The new lens had a slightly different diffusive pattern from the old one, but they both had the same part number printed on them.

I also ordered a new licence plate. An inexpensive way to make the bike look more up to date. I was able to fit it about 20mm higher than the old one and I decided to shorten the rear fender with the corresponding length.

Finally I gave the whole monocoque a good clean with a colour cleaner and after that a couple of layers with wax.

Drilling lots of holes

The rear sprocket fitted on the bike is home made from a blank, but no lightening (or decoration if you like) holes where drilled. Today I spent some time in the work shop drilling to give the sprocket a better appearance. I designed a pattern with 18 holes, but since I had to drill them steps with in increasing diameter there was an awful lot of drilling!
You can question putting that much work in a spocket that needs to be changed pretty soon, but I also consider it as a test. I came to the conclusion that it isn’t worth the work to make rear sprockets from blanks. In the future I will order them from Weires in Germany. I also found that Renthal makes a sprocket for a -92 Ducati 888 Corsa that will fit, so that is also an option.

Seat suite

Here is a summary of the work on the seat that I finished today.

It started with two problems:
1) The vinyl was loose on both sides of the seat and it didn’t look very nice.
2) When I tried to dismount the seat from the monocoque the fastening nuts was very rusty and almost impossible to remove.

With lots of WD40 and careful use of a hot air gun I finally managed to remove the nuts and the seat. I decided that I needed to re-glue the seat vinyl, and also to make a new fastening bracket from stainless steel.

I made the new bracket from 3mm stainless steel and slightly larger than the original. I also used about 5mm shorter screws since the length of the originals made it difficult to remove the seat. A friend at work has a TIG-welder and helped me welding the screws to the plate.
To attach the new bracket to the fibre glass base of the seat I used an adhesive film that’s very easy to work with and has very good adhesivity. With the new bracket in place I glued back the piece of foam I cut out using a contact adhesive Casco Kontaktlim S9 Super from Akzo Nobel. The adhesive was chosen after recommendations on Internet forums for Car audio builders. It’s a good adhesive for gluing vinyl and withstands heat on a hot sunny day very good. When the foam was back in place I gently sanded it to get a smooth surface. I guess that very small irregularity will been seen through the vinyl when it is stretched over the foam.

I carefully cleaned the edges of the seat base and the edges of the vinyl and applied the contact adhesive. From the Car Audio people I learned that vinyl can be stretched quite a bit if it is gently heated with a hot air gun. Taking grate care not to overheat the vinyl I warmed it and stretched it back in place. It was easy to work with the vinyl and the adhesive seemed to work well and felt very strong.

I’m quite satisfied with the result and it feels really good to be able to put the seat aside and know that it is ready!


Loose vinyl and old bracket


New bracket and adhesive film


New bracket installed, foam glued back and sanded


Gluing the vinyl, vinyl back in place

Clutch mounting

Time to assemble the clutch basket and drum. The screws for the clutch basket should be mounted with some Loctite 510 sealant to prevent engine oil from getting out to the clutch. I got a tube of Loctite 510 when I bought some ball bearings for the engine. It wasn’t cheap: 50ml cost me 250SEK (about 27EUR) but I only needed about 2ml for the screws so I can change a couple of clutches!

When tightening the basket screws I invented a new high tech tool. A piece of plywood through the basket and against one of the screws for the inner clutch cover held the basket while I was tightening the screws. The torque is only ca 30Nm so you don’t need much force to hold the basket. The clutch drum nut is another business. About 180Nm so I got good use of the new tool i made yesterday. Unfortunately the design was a little poor, so I bent the handle (but I got the nut in place alright). Back to the drawing board for the tool!

Back to the Keihins and a clutch tool

Today I cranked up the welder and made a clutch tool from some old steel clutch discs I got from a fellow Ducatisti. A must have to tighten the clutch drum nut!



Last week I took some hours at the shop at work and turned a wire wheel for the Keihins. After some minor adjustments today I was ready to assemble the carbs and throttle handle to see if everything was working alright, and believe it or not, it was! Now I will go ahead and order a return spring and the jets needed for a baseline setup.

The success with the carbs gave me a really good feeling! Spring is closing in and I am finally starting to put things back together.

Getting heads ready for blasting

As you can see, the cylinder heads don’t look very nice. The plan is to blast the heads to get rid of loose paint and aluminium oxides. To avoid getting blasting media in the camshaft bearings and other interior parts of the heads, I made covers for all openings.

The plan is to blast the heads and leave the aluminium surface without painting. I’ve been asking around what blasting media to use and it seems like the best choice is a soft media as crushed corn or walnut shells.

My friend Julius has a blasting cabinet at work and is going to help me with the heads as soon as we can get some proper blasting media.

Re-spin on the alternator rotor

As mentioned earlier I had a problem mounting the rotor since the generator cover didn’t fit when everything was mounted. I started off by talking to Josè, the previous owner of the bike, who also fitted the racing alternator. He said that when he removed the original alternator there was no washer inside the nut. He had fitted the convex washer with the racing rotor. This made me confused!

After consulting Kenneth at Biscaya Racing and the spare parts list things started to lighten up. On early engines there is a folding washer and another type of nut. When matching my engine number with the spare parts list I should have the newer configuration, but apparently that is not correct. My conclusion is that my engine should have the thinner folding washer instead of the convex one. The nuts are also different.

I now had the choice of getting a new washer and nut or machining the rotor to make space for the parts a already got. Since there must be a reason that Ducati changed the nut and washer and stuck to the never solution, I choose the latter.

After measuring everything ten times the rotor was set up in the turning machine and I turned out a 2.5mm deep pocket giving enough space for the 2.2mm thick washer. Once again I mounted everything and tightened the nut to 186Nm, but this time the cover slided perfectly in place. Here I used a gasket instead of silicon sealant. I also changed al the cover bolts for stainless ones.

Cleaning of valves

There was quite much build up of carbon deposits on the valves. I got a tip from my Ducatisti friend Martin to use vinegar essence to dissolve the deposits, and it worked very well. The intake valves where easy to clean, but the exhaust valves needed some more work.

In the picture you can see one cleaned intake valve and one left just as it was when removed from the head.

Seat surgery

I had great problems removing the seat from the monocoque since the bolts and nuts where all rusted. The seat skin had also begun too loosen on some places so I need to partly remove it, clean the surfaces and re attach it. I used a hot air gun to help me loosen up the glue a bit and then I could peel of the skin.

When the skin was off I intended to change the rusty bracket with the fastening screws for a stainless steel assembly. My first idea was to just lift the seat foam and remove the bracket, but the foam was glued to the fibre glass seat bottom so there was a risk that I would damage the foam if to much I tried to remove it. Instead I used a sharp filet knife to cut a hole from the top of the seat foam. I tilted the knife to get sloping edges. That will make it easier to glue the cut out piece back again.

The cylinder heads – Vertical head

While the investigation about the non fitting generator cover goes on, I started to disassemble the cylinder heads. They don’t look nice at all with loose paint and lots of oxides, and the plan is to have them glass bead blasted, but before I can send them away for blasting I need to strip them down totally and mask all surfaces that I want to keep.

I started off working with the vertical head, but before I took anything apart I measured the valve clearances. I know that the former owner of the bike was happy on the revs, so I was al little curious. All measures where out of spec. but I found nothing unusual.

The camshaft was marked OHT. I don’t know what that means. Perhaps someone reading this can help me? Send an E-mail or add a comment!



To extract the rocker pins I needed some tool. Basically I copied the Ducati tool nr 887130120. To remove the closer rocker you need a tool to hold the spring in position. Again I copied the Ducati tool (nr 887130143), but added no handle.



All rocker pins but one came out real easy. The last one needed some convincing by the heat gun. All rockers seemed OK except one closer rocker that had a bad wound in the chrome layer! Failing rockers is a known problem on Ducati 4V engines, but I have never heard of a rocker failure on a 2V. My guess is that the clearance on this rocker was set to tight and the rocker has suffered from that. Of course I examined the camshaft for damage but it seemed OK. Just to be sure I will bring it to the shop when buying a new rocker to get a second opinion.

Inner clutch cover

Since I ran into some problems with the generator side of the engine I continued with the clutch side. The new inner clutch cover is painted and ready for mounting, but before I do that I will ad an extra feature:
On both our bikes we have seen the common Ducati problem with a “milky” oil level window. This happens because moisture in the oil condensates on the cold glass window. Here in Sweden all houses have got double or triple glass windows for insulation, so why not try the same concept on the Ducati engine? I made a plastic window that is glued right on top of the original oil level window, and the idea is that it will raise the temperature of the inner glass window to avoid condensation. We’ll see if theory meets practice this time…

I was told by my shop that the gasket for the inner clutch cover isn’t sold anymore so instead I used a silicone sealant. By filling some sealant in a small syringe it was easy to apply a small amount. Start dating a nurse if you can’t get them elsewhere!
If you look carefully at the picture you might notice that all the cover bolts are changed to stainless. My intention is to change all bolts that are out in the open for stainless steel bolts.

When I bought the bike a vented clutch cover was mounted. Since I wanted to reduce clutch noise and give the clutch better protection when doing track days I decided to get a closed cover. On German Ebay I got a cover from a 999 for a decent price. I was a little surprised when I got it and found that it was made from steel, since I thought all Ducati clutch covers was aluminium. Later I learned that they went from aluminium to steel about -97 -98. Anyway, the steel cover might be a little heavier, but I think it’s strong and gives the clutch good protection in case of a crash. In the picture it’s mounted just for test since the clutch basket is not assembled yet.

Neutral light switch

The neutral switch was damaged so I got a new one that arrived with some other parts the other day. In order to get it to work properly you need to choose the right shim. The procedure is not described in the Ducati work shop manual, but you can find it in the Haynes manual. I quote it here since it’s not an unusual problem on Ducatis that the neutral light comes one while driving. Changing the shim will fix the problem!

Shift the transmission into neutral. Tum the ignition ON – the neutral light should be ON. Now unscrew the switch and note the position where the neutral light goes out; this should the switch. If the light goes out before a half turn of the switch the shim must be replaced with a thinner one. If the light goes out after a whole turn of the switch the shim must be replaced with a thicker one. Replacement shims are available in 1 mm, 1.5 mm and 2 mm thicknesses.

As usual you should be a litlle carful with Haynes. Here they are wrong about avaliable thicknesses. Here's the Ducati part numbers for shims with 1.5, 1.0 and 0.5 mm thickness:

5 0504.03.085 Gasket th.1,5
5 420.2.000.8A Copper gasket th.1
852.1.111.1A Gasket th.0.5

First real problem!

When I bought the bike it was equipped with a Racing alternator capable of producing 150W. The previous owner had quite some problems starting the bike, and I think the problem persists of several factors, one of them being the racing generator not giving enough power.

I’ve been waiting for some parts including the rubber gasket for the alternator cabel feed through, but today they finally arrived and I could continue to assemble the alternator and cover.
I borrowed a torque wrench at work at calibrated it to about 9Nm, the general recommendation from Ducati for M6 screws. Mounting the stator was pretty straight forward. I used some weak Loctite for the screws holding the winding as specified in the work shop manual.



But when I was mounting the alternator cover to the engine I ran into problems. The cover wouldn’t fit! When tightening the screws there’s a 2mm space between the cover and the engine case!
I removed the cover and started to examine things. Finally I discovered that the flyweel nut was only half way on the threads of the crankshaft! Luckily the threads weren’t ruined when I tightened the nut!

No other thing to do than to remove the rotor and flywheel again. Now the strange part: When measuring the racing generator rotor and spacer they stacked 29,5 mm on the cranskshaft. The corresponding measure for the stock (?) rotor was 37 mm. Further analyzes showed that it lacked about 2 mm on the shaft to fit the cover.

The only explanation I can find is that either the wrong fly wheel centre or rotor is fitted on the bike. I’ll consult the mechanics at the Ducati Stockholm store to see if they can tell me what’s wrong.

Mounting the alternator nut

Time to mount the alternator nut. After discussing with an experienced Ducati workshop I decided to get both a new nut and washer for the alternator/flywheel.

Ducati states a tightening torque of 186Nm but no Loctite. I decided to ad a drop of Loctite 243 (Medium strength oil resistant) just to be sure. I have heard of several Ducati owners that have suffered from loosening alternator nuts.

My home made tool for holding the alternator rotor now came to use and was found to be working perfectly! A long bolt in one of the engine mounting holes acted as a support for the tool.

Another example of Zink plating

Today I zink plated the plunger cap for the gear shift mechanism located at the back of the engine. I’m really amazed what you can do with old rusted parts!

I'm back!

Back home again after one week of skiing holiday in Canazei, Italy, a very nice village in the Dolomites. Unfortunately there hadn’t been any snow in two weeks and before that no snow since new year, so it wasn’t possible to do any off-pist skiing. We had to stick to the well prepared pists, and enjoy the sun and the nice restaurants in the slopes.

This time of the year there wasn’t any bike in sight, but a waitress at one of the apre-ski places we went to commented on my Ducati sweater, and told me in struggling English that her brother owns a 748!

The lack of bikes was compensated by other Italian culture i.e. food and drinks! As a souvenir I brought home four different local Grappas. The rightmost one is cask aged for ten years and tastes almost like a cognac, with rich tones of vanilla and coconut! Yummie!

No news

No update for a long time now I'm afraid. I've been busy doing other things and also done some travelling for my company. Don't expect any updates in the next week either, since there will not be much time to work on the bike. However I have ordered all the gaskets and other parts I need to start the assembly of the engine so the real fun will begin shortly! I'll be back in a week or so with updates!