1996 916 Rebuild

With the 37/32 valve do you need to be conservative with cam timing / overlap? Any chance of the valve heads clashing with each other?

 

Wired-up, plumbed-in, chain fitted. Instruments mounted, clip-ons fitted, brake calipers re-furbed with new seals, bleed nipples and banjo bolts. New brake and clutch reservoirs. Sorted out the manky clutch slave cylinder. Dismantled, cleaned, greased and re-assembled "foot controls". Changed all the old rubber hoses for plain black silicone.







Being injected, there's a friggin' lot of wiring, some of it pretty foul after 20 years (several laid up in damp sheds, hence the full-on rebuild). I had at some point in the past bought secondhand replacement front and rear looms, but when I tried to join it all at the battery box / relays area there was nowhere to plug in the regulator/rectifier. This is a replacement one - the original blew up coming down from the Val D'Aosta towards Milan on the way to Monza to watch the WSBs a long time ago (which is a story in itself). The design was changed because early bikes had so many issues, and an adaptor loom was supplied to make the change; this is the part I was missing. So I made a new sub-loom to keep the exotic Italian smoke well and truly inside the electric pipes.



I removed all the existing (single-phase) alternator wiring right back to the stator coils and fitted some fat wires. I also cleaned all the crap out from under the fuel pump, changed all the hoses and fitted a new filter.



Bought oil, can of petrol and a battery....almost startup time, 20 years to the week since I bought the bike! Need to add brake fluid, oil, coolant and turn the engine over by hand with the plugs out until I'm sure the oil pump has primed and oil is making its way round. The external oil lines to the heads are pretty long....

 

I have some bleed nipples, yes. Might be a bit skanky, but I can run the wire brush over them. You want me to post them you?

 

I had put the whole project on the back burner, being disillusioned by the bike failing to start the moment I hit the button the first time after the full rebuild. Over Christmas I met up with my cousin (countcoupe on this forum) who has a couple of Ducatis - an 851 in boxes and a 900SS with 916 front-end, FCRs and...err...engine work? Help me out here, @countcoupe! While we were chatting he recalled the time his 900 hadn't started after reassembly, and it turned out that the reason was that he had fitted the plug wires reversed front to rear. This got me thinking that I really needed to get back to my own bike and go through everything again - it could even be as simple as countcoupe's problem.

Once I got thinking about it, I persuaded myself that there's no way I would have made that mistake and in any case I was sure I'd double-checked orientation and connection to the (replacement) coils when I'd fitted them. Then I remembered that last time I'd taken a look at my bike, the fuel pump had run when the ignition was switched on, but that it had continued running instead of shutting off after 5 or 6 seconds. This struck me as odd, and maybe something I should be concentrating on, so after some quick Googling and reading of forums the most frequent suggestion was a faulty ECU or EPROM as it's the code in the EPROM which shuts off the fuel pump if the crank position sensor senses that the engine isn't turning (essentially to prevent a crashed bike from becoming a flamethrower).

Bit of history here:- in 2001 I was commuting to work between Kirkby Lonsdale (ish) and Halifax and the 13-hour days with travel meant I wasn't using the 916 very much and it was left standing for quite some time. On the one occasion I dragged it out for the ride to work it snapped a cambelt and bent a couple of valves, and I ended up rebuilding it with SP heads with G/A cam combination and some high-comp FbF pistons (20mm gudgeon pin...the SPs have Pankl rods and a 21mm pin for Ducati nerds). Because I was still running a single-injector setup and had a 1.6M ECU (the 916SPs ran twin-injector and P8 ECU) I needed a new EPROM and was advised to use the 853SP Ultimap chip which was intended for big-bore 748 conversions running SP cams. I never really liked the bike in that configuration - the G cams are long-duration and only really come alive over 7k RPM, when the power climbs quite steeply and it's a bit tiring riding a peaky bike which is used entirely on the road these days.

Last night I pulled the rubber bung in ECU housing and prised out the stock EPROM, which I'd reinstalled during the rebuild now that I'm back on Strada cams. I then read the Ultimap packaging which stated "Insert the chip, together with the interface board, into the ECU EPROM socket". I peered into the hole in the ECU cover and the little interface board peered back at me. It would appear that when I removed the Ultimap I'd left the daughter board in place in the EPROM socket, and had inserted the stock EPROM into the board. I removed the interface board, re-inserted my EPROM directly into the ECU motherboard and turned the key - hey presto, the fuel pump now runs for 5 secs then stops! Too late in the evening to wheel the bike outside and try to start it, but I can't wait until the weekend.

Quick search revealed I'm not the only person to have this issue - see posts #5 and #6 in this thread:-

2001 748 ECU/EPROM issues - bike won't start with stock chip - Ducati.ms - The Ultimate Ducati Forum

 

Well, I finally found time yesterday to wheel the 916 off the bench, out of the garage (just in case of, like, a huge fireball...) and tried the button. Took a bit of cranking, but it started and ran...roughly. Sounded more like a 450 single than a sophisticated twin. Then I remembered I hadn't re-attached the horizontal plug lead after my earlier troubleshooting. It ran a LOT better with both leads attached...then I noticed it was pissing oil from behind the vertical cylinder belt cover. Maybe I nipped an O-ring round the cam carrier on the vertical exhaust cam?. Not sure. I called it a day after that and put the bike back on the bench - will take a look at the leak soon.

Edited to add:
Just re-read the post above. Makes me sound careless, like I didn't pay attention during assembly, but nothing could be further from the truth. This bike is essentially blueprinted - everything is set back to the factory settings (the settings before the factory relaxed them all to increase service intervals!).

 

At the time I started the rebuild (believe it or not, 2007!) I couldn't find anyone who could match the dirty-bronze frame paint, and I had seen a gorgeous 996SPS build with black frame, so I went for it. Pic attached.