Updates on the 748, the ending is painful... Bike was due a service, including the belts, I'd normally do it all myself but with the oil weep needing attention I thought I'd tackle all the standard bits myself and leave the weep, belts and valve clearances to the garage, more on that later. I'll be honest I've not been the kindest to the bike during my ownership and under the fairings it was looking decidedly grubby so first on the list was to give everything a good clean down. It's well serviced and gets a good external wash fairly regularly but it's not had a deep clean in a long time. Fairings off and tank removed and drained the first thing I noticed was how filthy the airbox was. Seemed to be a combination of oil reside and fine sand, I'm hoping the oil got a hold of most of the sand! Cleaned it all down and replaced the airbox seal as it was looking decidedly second hand. As I was going over things I noticed that the fuel feed pipe between the tank and the injectors was looking worse for wear so that got replaced. I then cracked into the tank to replace the fuel filter and check over the pump and hoses. I was amazed at how clean the tank is for a 21 year old bike! All the hoses and the rest of the assembly were in great condition but the fuel filter was stamped as 2008 so it definitely needed doing. On reassembly I was a bit baffled by the gap between the pump flange and the tank but as you may have seen from my other thread 'they all do that sir'. Next up was an oil and filter change. The last filter never seemed to seal correctly and I was always chasing a little weep. Checked the mating face and all was good and thankfully now the new filter is on there is no such issue. While everything was in bits I also replaced the spark plugs and air filters (went for pipercross) for good order. I noticed a tiny bit of oil around the vertical plug, I can only think that this is due to a tiny amount of porosity in the head. Very small though so hopefully not a huge issue but definitely something to monitor. Brakes stripped and cleaned and clutch checked and cleaned of dust and we were all good to go again. I then had the bike booked in for MOT and the outstanding works this week, the general feedback from the garage had been that about £1200 was a good base figure assuming that the engine could stay in the bike. I got a call confirming that the source of the leak was the vertical cylinder base gasket however it would be an engine out job to sort, the new estimate...£3000. I told them to pass on that, MOT the bike and that I'd come up with a plan. I was then in the garage this morning getting the BMW MOT'd (clean pass thankfully!) and asked what their estimate would be if I was to remove the 748's engine and hand it over to them for the work. A bit of head scratching and they came back with £2000! I collect the Ducati on Monday and will challenge them on their estimate going from £1200 with the engine in the bike to £2000 with the engine out but I don't see them budging much. £2k seems a bit spicy for the works that need doing (valves, belts supplied by me & leak) but I really don't have the appetite to do it all myself as time is pretty scarce at the moment between work and a toddler. Not many options in Aberdeen for the work, I've always used this garage so would be confident in the quality of their work and would feel a bit unsure committing to one of the others. Thoughts and feedback welcomed though, really not sure what to do for the best.
At the prices you've been quoted, might be worth taking the engine out and getting it couriered to a competitive and reputable workshop for the work? Can't imagine there are many folks in Aberdeen, but @Derek might be a good person to ask for a recommendation?
I know personally that Gary Baird at B&B in Lincoln knows his onions, by reputation there's Cornerspeed, Louigi Moto, Cellier Ducati (used to be called Ducati John). Those are the ones that spring to mind. Should be able to get a good steer on here, and there may be folks more local. The most northernly I know of is the chap at Knockhill.
£2k to change the base/head gasket? Probably £100 worth of parts and a few hours labour so, unless they're doing an engine rebuild at the same time it sounds a bit steep.
Right, I have the bike back and I think I'm going to crack on with it myself later in the winter, most likely January / February. Probably still going to get the valve clearances done by a pro so the plan will be to strip the heads and barrels off, send the heads to someone to do the clearances and inspect the rockers and then put it all back together with fresh gaskets and belts. Anything else I should be doing while I have the heads and barrels off? I think the only tool I'm short of is the correct one for torqueing the head nuts, should be easy to get hold of.
Tyler at North Motorcycles in Leith, Edinburgh would be a good shout for a not too distant and very knowledgeable guy for any work you want to farm out. Really nice guy.
Thanks for that, I spend a reasonable amount of time down that way for work anyway so will give them a shout when I'm ready.
Hi Jimmer, Aberdeen based myself, I’ve heard good things about Jopps albeit never used them myself, give me a DM if you need a bit of help with the work!
So no further on with any of my plans really because oddly the oil leak appears to have stemmed itself...however; Here’s an odd one for all the great minds on here! I’ve a strange running issue where the bike will start stuttering, backfiring and running on one cylinder intermittently. Bike always starts and warms up great and then, about half an hour into a ride the issue starts. If I’m stationary the idle weakens to around 900-1000rpm and it sounds like it’s missing on one cylinder, it won’t rev cleanly and to pull away you need to slip the clutch with at least 6k rpm wound on or it feels like it wants to die. If I’m on the move it manifests by running rough, stuttering and surging a bit up to about 6.5k rpm, above that and up to around 8k it clears up but the throttle response is pretty wooly and then above 8 it fully wakes up again. On closed throttle it seems to backfire a little, can’t pinpoint it to the airbox or the exhaust as I’ve always got earplugs in but this bike has never been ‘poppy’ so it’s definitely a symptom. As you can imagine this is tricky to ride around. Switching the bike off for 10 seconds or so does seem to rectify it for a while. Temperature seems OK and there’s no obvious signs of anything wrong externally. It’s maybe using a little more fuel than usual but I’ve not been keeping too close an eye on it so can’t be sure. It first started before my trackday last year at Knockhill. On the ride down I started experiencing the issues and assumed it was bad fuel. Brimmed the tank with some fresh super and when I arrived at my accommodation I pulled plugs and leads and generally had a look around for anything obvious but couldn’t find anything. On the morning of the trackday it was better but still not right but as soon as I was on track it was perfect and ran all day racking up 80odd laps. It then took the 2hr ride home without fault. Subsequent times it has happened there are no real consistent conditions. Twice it happened on wet rides so I assumed it was moisture (I’d also washed the bike before the trackday) but most recently it’s been on bright, dry and cool days. The bike hasn’t seen water for months. I can also rule out water in the tank or issues with any of the fuel hoses has I’ve been through all of them over the winter. Plugs have also been replaced. Could it be an injector on the way out? I thought about ignition pick-ups but I don’t think switching the bike on and off again would change anything it they were breaking down as the bike gets hot. The only thing that I changed / messed with prior to all of this starting was I removed my titanium Akra pipes and fitted the standard ones before the trackday. I don’t think that this could have caused the issues as the tuning of the bike wasn’t altered when I fitted the Akras as it seemed to run fine but maybe I upset something. It’s so frustrating, for the time the bike runs well I’m totally smitten, when it starts messing me about I feel like setting fire to it!
Could be any number of things. If it’s been running rich a long time (I guess it was tweaked richer for the Akras) then you could have coked up the plugs but I assume you’ve checked that, it could be moisture in the ecu causing corrosion on the board or around the plug connector. It could be a coil pack getting warm that’s slightly faulty, could be an earthing issue that shows up when the engine is warm (engine earth strap is good and not corroded?), could be a gummed up injector. Good luck.
Indeed, but worth checking/setting the TPS. I had the TPS on my 916 move a little as one of the fixing bolts had broken causing it to flex when the throttle opened and it ran like a bag o'shite, especially at lower RPM.
So in true Ducati fashion the bike ran absolutely perfectly on my return journey on Friday afternoon, I get the feeling I'll be chasing this for a wee while...
I had a similar issue with my 748E in 2002, it was a perfect bike mechanically, regularly serviced and only had 5k miles on it so wasn't worn out. Basically it would ride fine then start miss-firing and it would chime in and out. It went to MotoRapido who replaced the ignition solenoid as it was a pretty big 'cut' when it happened, they suspected that the ignition was completely turning off. Anyway this didn't cure it, and at a donnington trackday it cut out on the main straight. It went back to MotoRapido who had the bike for about 4 weeks, they switched the ECU, and didn't have a single issue, they then put my one back in, and had no issue again. They concluded that moisture had got into the ECU where the EPROM Rubber bung is, and that was causing the miss-fire when it warmed up. The other option is that it's genuinely a 'dry' solder joint and as the bike heats up and the electronics heat up it 'opens' the joint and starts messing around, not entirely unlikely given the age of these ECU's now.
Washed the bike yesterday (carefully!), started it to warm it through and help the drying process, got up to about 80deg and it started idling lumpy and struggled to rev. Holding a little steady throttle the revs would pick up to about 2k rpm, run rough as f**k and backfire into the airbox, before clearing up and revving up to around 4k. If I let the throttle off and did the same again the bike would respond in the same way. Switched it off an restarted it and it was perfect...for a couple of minutes and it was back to the same issue. I've not done any diagnostics since I last posted but it's clear I need to do some digging. Typical, the weather is getting better and the wee Duc is being temperamental and the big GS has a parasitic battery drain issue
This absolutely stinks of a heat related issue, such as a connection breaking down either in a coil (or ignitor or whatever they are called on the pre stick-coil bikes) or a ECU issue. in Electronics stuff in the past, we even had chips lifting out of the chip sockets when they got hot.
