Flatland Dan Posted June 14, 2004 Posted June 14, 2004 I have owned this 2003 LeMans 2 weeks and 350 miles. A week and a half of that the bike has been sitting in the shop. At 2000 rpm to about 4000 rpm, acceleration is difficult. It stumbles and backfires through the airbox and acts just like a lean burn condition on a carbuerated bike. At 4000 rpm and above, it won't run at a steady throttle setting. However, it will run great guns above 3500 rpm if you are accelerating hard. TPS settings, air screws, throttle body balance, timing event sensor, valve clearance, and coils all test good. The computer is not throwing any codes and the dealer is stumped. If this was a semi at work, we would be replacing the computer. Has anyone else seen this before?
al_roethlisberger Posted June 14, 2004 Posted June 14, 2004 Since it is at the shop anyway, I would suggest swapping the ECU from another bike to eliminate that possibility. I had a bad ECU early on, and had similar mysterious running problems. al
Guest rotorhead Posted June 14, 2004 Posted June 14, 2004 I had a similiar problem and after replacing most of what you mentioned it turned out to be the inlet air temp sensor in the airbox was defective giving inaccurate air temp indications to the ecu.
al_roethlisberger Posted June 14, 2004 Posted June 14, 2004 Also check the valve lash. Ultimately this was found to be the primary issue with my bike. From the factory, the valve lash was set too tight(but to US spec), and once hot, the bike just wouldn't idle. al
Flatland Dan Posted June 15, 2004 Author Posted June 15, 2004 The dealer called this afternoon and said she is ready to ride. He set the TPS at 4.0. I don't have a factory service manual yet but, it seems I read somewhere on this forum that the standard is somewhere around 3.5. I am hoping this is not a band-aid masking a problem further on down the line. Thank you for all of the suggestions. I also received some good suggestions from when I posted my introduction yesterday. I'll burn some midnight oil and drink a homebrew while checking those out. thanks again, Dan.
big unit Posted June 15, 2004 Posted June 15, 2004 Hi, how is your bike going now. Have you checked that their is no water in your fuel tank. Water can get in if the drain valve gets blocked for some reason as it pools near the tank cap seal and when you open the cap the overflow will pour into the tank. It happened to me.
Guest rotorhead Posted June 15, 2004 Posted June 15, 2004 Antonio just does not like those PCIII's does he??
Mike Stewart Posted June 16, 2004 Posted June 16, 2004 Does your bike have the stock exhaust or does it have an aftermarket exhaust system? When I installed the Mistral exhaust on my 03 Rosso, the bike would cough and even die while riding. The only way to fix the lean condition was to install a PCIII. World of difference! thumbsup: I am a firm believer in the PCIII. Mike
gthyni Posted June 16, 2004 Posted June 16, 2004 The only way to fix the lean condition was to install a PCIII. No no no. that is the only way! The smartest way is to remapped the stock Marelli ECU The coolest way is install a third party ECU to replace the Marelli unit like Cliff's My16M (plug-n-play) or a race ECU. The PC works OK and is kind of cool, but it is not an optimal solution since it add an extra box and complexity to the engine control which is not really needed.
F344 Posted June 16, 2004 Posted June 16, 2004 I found a link to the "My16M" http://www.jefferies-au.org/My16M/index.htm Does anybody have links to race ecus? Also I couldn't find any threads on the My16M. Is anyone here using it? It seems to be reasonably priced at $700 Au (a little less than 500 US) Thanks, Frank
gthyni Posted June 16, 2004 Posted June 16, 2004 sorry for not linking to My16M, Cliff is here from time to time. The 1.5M version that fits V11s has just been made available and several people are pondering give it a try - including me. Motec make race ECUs which should be adaptable (Ducati versions). Quiet expensive and some work required.
al_roethlisberger Posted June 16, 2004 Posted June 16, 2004 Cliff only has a ~couple of his 15M versions of the My16M available for testing, and one of the "beta testers" here in the USA is Carl Allison. Both Carl and Cliff are members of the forum, and Carl is very active here, so will probably see your post and respond. We have had some very lengthy discussions here on the My16M and what it would take to fit it to a 15M equipped bike, hence Cliff's interest in making it work. Interestingly, one of the biggest hurdles was finding a source for the ECU plug <_> ...that's one reason why Carl was asking for someone's dead PCIII the other day Anyway, I don't know where Carl's tesing is at right now, as he's still rebuilding his crashed Sport. But ping him, or start a new thread with a title something like "Status on the My16M ECU" ... and I'll bet Carl and Cliff will notice it and let us all know how things are going. We haven't heard an update in months. Here's an interesting sidenote though.... one of the benefits we've noted for Cliff's ECU is it's ability to run closed loop, unlike how our bikes are currently delivered. Yet, Dynojet sells an adapter that negates the O2 sensor on closed-loop bikes to "improve performance" Interesting... I don't know what to think on this one.... The system is designed to read the Oxygen sensor under certain conditions and temporarily change the air/fuel ratio. The closed loop circuit has a very limited operating range, which is only in effect while holding a steady speed at certain rpm's and throttle positions. In this limited area, the stock system (with or without the Power Commander) will gradually and temporarily lean out the air fuel ratio in an attempt to achieve an air/fuel ratio of 14.7:1 (stochiometric). The Oxygen sensors can be disconnected but this will trip the F.I. dash warning light. al
Cliff Posted June 16, 2004 Posted June 16, 2004 Hi all I've still got Carl's ECU. He hasn't been ready for it yet and I've been doing some software enhancements in the meantime. I've just finished my bit so I'll get it in the post to him next week. His will be the first My15M so you wont find anything about it here. There are are few Sport 1100 and Centauros with it so you can find some bits on http://morini.com.au/phpBB2/viewforum.php?f=1 and http://www.centauro-owners.com/phpBB2/viewforum.php?f=1 One of the best write ups about My16M is this site http://www.kolumbus.fi/koivupiha/ecu.htm
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