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On my trip to Monza I noticed a strange feeling on the Falco that got progressively worse as the miles racked up. I've got my suspicions, but your input would be gratefully received.

On a steady throttle the bike seemed to be pulsing power and I could feel it through the pegs especialy. It's difficult to put into words, but it felt as if the it was hunting for gas, finding it then loosing it again.

On an open or closed throttle the feeling went away, but as most of the big runs were steady cruising it was really starting to bug me, to the point that I was leaving it a gear lower than I needed just to get up the rev range where it wasn't as pronounced, but still there.

I feels like a click, didn't notice a clicking noise (helmet and earplugs), but if you can imagine what a click feels like through the pegs and a feeling of surging through the whole bike.

Theorise away chaps. Once I've had some feedback I'll chuck in my tuppence worth, I don't want prejudice any free thinking at the mo.

am hazarding the first guess at the injection management system.... electronic in origin?

standard eprom and mapping in there?

btw - silly question, but was this more noticible at altitude??

Aladinsaneuk wrote:am hazarding the first guess at the injection management system.... electronic in origin?

standard eprom and mapping in there?

No - chipped, air box mod and open cans

Aladinsaneuk wrote:btw - silly question, but was this more noticible at altitude??

Good question - but not more noticeable at altitude. Unrelated to the problem though the idle did drop to almost stalling point high up in the Alps well into the snow line.

Are the pulses/clicks in time with the pistons? Maybe every other combustion is not at full power, i.e. the mixture is right for one ignition and then for the next ignition there is not enough fuel/air or too much fuel so the next ignition is not at full strength.


Not much help I know... its basically what Aladinsaneuk said.

Clicking noise could be pinking/surging due to running weak......or even rich up in the alps.

Check out the plugs to confirm or have it dyno'd to see just what IS happening.

Fuel injection pressure?

Either system pressure is weak/weakening somehow
Injectors are fekked *thinks.... no discount that one*
Errm.. or pressure is being reduced by a vacuum from the tank maybe.. fuel tap and piping playing up?
Loose sensor possibly?

Dunno. Interesting problem tho'

I reckon it's a language/accent problem.







What is derv in continental lingo?

*coughs loudly*

Well if PETROL is Petrol in Uk...... and DIESEL is Diesel in Uk....

Eh Sam...

In Italy petrol is gasole and diesel is benzine,

that'd give your bike the gypes if you mixed 'em

in english we say petrol.. in foreign we say "PETROL"

all depends how loud you shout i guess

How worn is your chain?

I've noticed that at about 4k RPM, I can feel my (loose and worn out) chain flapping up and down as it goes loose - tight - loose - tight.

(Yes, I'm going to get it replaced as soon as I can afford it! Got a loan payment and registration (MOT / Road Tax for you English people) due this fortnight.)

All interesting and a bit scary.

My thoughts are worn chain. I tightened it before the trip and may have made it a bit tight. I'll check for tight spots.

Also I need to synch the pots which may be the surging issue.

Good call on checking the plugs tough. Many a problem can be identified by such a simple task. I should have thought of that.

Any more?

Falcopops wrote:Any more?

It's a blue one innit?

Nuff said!



Balance throttle bodies, sync the cylinders, check fuel pressure and errr dunno what else really.

Falcoholic wrote:It's a blue one innit?

Oh yes so fast you rarely see them!