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Hi - I'm hoping for some advice as to what to next check on my '99 Falco which will not start after an engine swap.

I have checked the obvious - all sensors are plugged in and there is a good spark at all 4 plugs which I have removed and cleaned. Battery is now fully charged and reads 13.8V.

When I try and start the bike it turns over fine and has backfired a couple of times and spat back through the throttle body. Pouring a bit of fuel down the throttle body does result in a bit of action but often just seems to 'lock' up the engine. No diagnostic codes reported.

The original engine had the crank position sensor combined with the generator wiring whereas the new engine had a separate CPS. The casings were therefore swapped over to put the old cover on the new engine so the wiring would stay the same. I do wonder if this is the problem in that the old and new casings/ CPS are not compatible but not sure how to check.

Any suggestions as to what to check next would be most gratefully received!

Please note: I anticipate that I shall be posting a thread using the same title on Monday.

First of all welcome.....
If you have backfires you have a spark.
This would tell me the timing is out.
Have you connected the spark plugs up to the correct sparks plug leads?
Have you mixed the coils up when refitting them back to the frame? Ie the leads from the ecu to the coils?
Where in the uk are you? Perhaps one of our members could have a look.

Obvious question but is the new engine kosha?

What was it from?

Unfortunately I didn't fit the engine I bought it as a non starting project so I don't k ow the history really. The engine was bought from a breaker as a runner from ebay so I have to work on the assumption to start with that it is a good one.

Definitely is sparking as you say but the backfire to me suggests a timing issue. It doesn't look possible to wire the injectors up the wrong way around as the wiring just wouldn't reach and the same goes for the coils as one is at the front and the other at the rear but I haven't checked the ECU. I would doubt this will be the problem though as it will just be a big multi plug.

As I mentioned the one thing which stands out is the crank sensor as I know this is different between the 2 engines. I'll check the injectors today to ensure they are firing and if they are will have to dig further.

Blinkey501 - I am just outside Scunthorpe so I guess not that far from you if you are just outside Doncaster...

cmdrew wrote:Blinkey501 - I am just outside Scunthorpe so I guess not that far from you if you are just outside Doncaster...

Misterton

If you have a multi meter you can do a resitance test on the sensor, 150 to 350 ohms on the sensor side of the wiring with ign off is what you want to see !
PS Griff (AP) assures me that it is possible to connect the rear injector harness to front injector body. I also didnt think the wiring would reach but he's seen it done.
front injector green/black.grey/red wires

fatboy wrote:If you have a multi meter you can do a resitance test on the sensor, 150 to 350 ohms on the sensor side of the wiring with ign off is what you want to see !
PS Griff (AP) assures me that it is possible to connect the rear injector harness to front injector body. I also didnt think the wiring would reach but he's seen it done.
front injector green/black.grey/red wires

Thanks - injector wiring checked and correct. One hell of a smell of fuel now so taken the plugs out to let the cylinders breathe. Going to get a new battery and see if that helps and will speak to Griff at Aprilia performance as well. This will not beat me!

Just thought I would post an update on my starting issues...

Looks as though I have a Futura engine rather than a Falco. The differences seem to be that the Futura did not have a cam position sensor and have a different location for the crank position sensor. The previous owner had replaced the front cylinder head cover with the one from the old engine to keep the cam position sensor and the generator cover from the old one to retain the old crank position sensor (and wiring).

It seems from other suggestions that the later engine will not work with the earlier crank sensor unless the old rotor is also used - so I need to work out how to swap that over.

Whether the cam position sensor from the old engine is able to detect the cam position on the new engine I do not know as I am unsure how this sensor works. I assume that it detects something on the cam so hope that the new cams have the same markings. I may need to remove the front head cover to check this but I think the rotor is the first thing to do.

Well there's a can of worms!

No idea what problems there might be in trying to run a Futura engine with a Falco's ancillaries and ECU.

Hope you get it sorted.

cmdrew wrote:Just thought I would post an update on my starting issues...

Looks as though I have a Futura engine rather than a Falco. The differences seem to be that the Futura did not have a cam position sensor and have a different location for the crank position sensor. The previous owner had replaced the front cylinder head cover with the one from the old engine to keep the cam position sensor and the generator cover from the old one to retain the old crank position sensor (and wiring).

It seems from other suggestions that the later engine will not work with the earlier crank sensor unless the old rotor is also used - so I need to work out how to swap that over.

Whether the cam position sensor from the old engine is able to detect the cam position on the new engine I do not know as I am unsure how this sensor works. I assume that it detects something on the cam so hope that the new cams have the same markings. I may need to remove the front head cover to check this but I think the rotor is the first thing to do.

First and foremost the futura uses a different ignition system to the falco/mille

Hi all,

Did you buy the bike off a guy up stanley, co.durham way for £1,050p by chance. Spoke to him at length before the end of the sale and found it would be a can of worms to diagnose. Eventually got it out of him it was a futura engine in there

Wanted a spare falco for a track bike. Still looking. Hope you sort the problems out.

Yes I did - got it a bit cheaper than that as well and TBH even if I needed to put a different engine in I still still it is worth the money. I'm getting pretty close to sorting it I think - just need to swap the generator over and hopefully it will go - if not - well I'll have a Futura engine to sell and will have to go and get an RSV motor as apparently the early ones will swap straight in and I know where there is one!

Hi all,

Well, if you got it way cheaper, then, that's a good bike to buy. Like you say, just change the lump over. Sell on fleebay and you got another lump to go in, mint situation. Glad you getting it sorted