my 97' 748 runs an absolute treat in general but at low revs she runs like a bit of a pig. tick over is less than average but twist the throttle and you notice a distinct delay in response from the engine and lots of exhaust smoke to go with it. is there any adjustments/maintenance i can do etc. without plugging her into a computer??
adjust the throttle position sensor ...balance throttle bodies ...new plugs ...new fuel filter and should be good to go i got caught out with a dodgy coil once so mayb check them too...the connections etc
Don't forget check the air filters in the intakes. If these are blocked, it could be overfuelling. Is the MPG bad? Are you using race cans and chip too?
the smoking bit is slightly worrying CD - it could be from running rich but rings/valve guides do come to mind if not. A general tune/recce as suggested is a good start, depending on how the plugs look you could check the compression on both - oil consumption low/normal?
Thanks chaps. Fuel filter, Plugs are done. Air filters have been cleaned and lubed. I'm running a set of Termis but not sure if the chip is correct or not, it's blank with no markings. TPS and throttle bodies - best left to the experts?
Sounds like overfueling, I had a similar problem which was sorted by a mixture adjustment by a dealer some time ago. It's worth going the whole hog to get it right. Is it using a lot of oil?
Is it yellow? Maybe it's that? but seriously, the ecu needs to be matched to the termis. if its a regular ecu with straight through termis, then it would normally be running lean, using layman's logic, I.e. currently set up for choked exhaust would mean less fuel with bigger free-flowing termis and more likely to cause overheating. Oil level first, fuelling next, then valve timing, then rings, IMHO. good luck, Pete
If the tickover is too low, then there will be a tendency for a stutter when the throttle is snapped open. Up the tickover to where it should be. As for the "lots of smoke" then I hope its overfuelling on acceleration. Does it smoke on the over-run when up to temperature? = mechanical, rings ect. Does it just smoke under acceleration? = overfuelling.
Thanks for all the input people Just a couple of points to note - No she's not using oil - smoke only evident on throttle blip when stationary. No evidence on acceleration or run down. She idles at around 1k which actually I'm guessing is Ok. Air filters are impregnated in engine oil as origignaly done by the previous owner. Is this practice still advisable. New filter on the way regardless. New Iridium plugs - old ones look as they should. I have 2 chips - 1 marked with "748 Baines Racing" and the other "748s" in biro (other good pens also available!) I'm now running Termis and the "748s" chip appears to give a better response then I blip the throttle. Is there a market chip available for Termis?? Whats the best method for adjusting the TPS? She's red so knocks the yellow theory on the head!!!
If the air filters are standard ducati type they should be fitted dry, you say they are impregnated with oil this could be your puff of smoke when you blip the throttle, but some none ducati air filters do say oil lightly so it could just be over oiled or shouldn't have been, ? brian.
Cheers Brian, I'm not entirely sure what they are, they are oiled but have been cleaned regularly over the last year but I've never re-oiled them myself. But as previously mentioned, new Pipercross are on there way.
