Originally Posted by Pleiades

Excessively rich fuelling is the normal cause for this sort of thing.

Firstly are you sure there�s petrol in the oil? What are the symptoms?

Does the oil level on the dip stick rise, between checks? Does the oil on the dipstick or the oil tank smell of fuel? Is there evidence of a very sooty tailpipe? Has your fuel economy dropped off? Is the bike harder/easier to start or the same as before? In some extreme cases there may be evidence of neat fuel in the exhaust gases � hold a sheet of card up to the tailpipe and see what collects? Does it smell excessively petroly? Does the fuel pump do its normal short priming cycle when you turn the ignition on and then go quiet, or does it keep running?

Possible reasons�

If (and that�s a big if) it�s over-fuelling then something is causing the injector to spray excess fuel into the combustion chambers, which can�t all be burnt during the combustion. The unburnt fuel will cause bore wash and leak past the oil control ring and down into the crankcase where it mixes and dilutes the engine oil.

Which could be�

• Faulty ECU, or sensor(s) � unlikely as you�d probably see the engine management light come on.
• Secondary fuelling control set to rich (PC, Kev mod etc.) � unlikely as Kev designed his mod in such a way that it won�t cause over-fuelling even if set to full.
• Fuel pressure too high (fuel pump�s internal regulator is faulty) � more common though for low pressure or no pressure at all.
• Leaky/sticky injector � won�t trigger the engine management light and is probably the most common cause of over-fuelling (I�ve had this happen to me on cars and bikes over the years). Sometimes they leak when the ignition is on but the engine not running, sometimes they leak between pulses so they never effectively close/shut off.

If you have access to a diagnostic tool you can check things like the fuel pressure, sensors and ECU. You can remove the fuel rail and visually check for a leaky injector, but to check it properly you need specialist equipment.

I�m assuming everything was running OK previously with the same set up? What changed then? Did it start occurring after one of the mods was added, or did it just start doing it? Was a particular tankful of fuel the start of it? How long has it been doing this? Which model XT is it and what model year? Try and get back with the answers to these questions (and the earlier ones) and we might be able to narrow things down for you.

For starters, you could try running some injector cleaner through the fuel system. It also might not be such a bad idea to return everything to stock (maybe not necessarily the cans) replace the oil with fresh stuff and see if the problem goes away. At least it'll give you a blank canvas to start diagnosing any problems.

Originally Posted by Austinxt

Hi there,first off the dipstick smells like petrol, it starts and runs like normal altough has recently developed a slight tick from engine,there is soot collecting around the pipes, fuel pump primes as normal.and can be heard quietly whils bike is running. it is a 2013 xt x with 5000miles on it ,only had it a few months

Originally Posted by Pleiades

I assume (because you haven't mentioned it) that the oil level is not rising, it's remaining constant and the fuel economy is normal?

If the oil level isn't rising, pumps priming as it should and the bike is running fine (ticking over evenly, operating smoothly and performing as normal) then it's probably not over-fuelling. Have you checked the spark plug? Does it look a normal colour?

There maybe a clue in the fact you say you've "only had it a few months". Do you know when the oil was last changed? All "old" oil will smell slightly of petrol, particularly if the motor has been run for short periods/short runs and never gets to warm up fully. You yourself might ride longer distances and get the motor fully warm, but did the previous owner? I think maybe the ticking might not be the cause of the smelly oil, more a symptom that your bike's got old oil in it and it's lubricating qualities are less than ideal and possibly causing valve/timing train noise.

If you don't know when the oil was last changed, change it (and the filter) now. At least you'll have a known starting point to work from. See how you go after that. Monitor the situation (levels and smells) carefully.

No harm in dosing some fresh fuel with some injector cleaner too at the same time.