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That's too hard. I don't know your experience, so I can't tell what you have ever heard of or not. Can't you give us some hint?

AoS hat geschrieben:That's too hard. I don't know your experience, so I can't tell what you have ever heard of or not. Can't you give us some hint?

The point is not my experience but the people on the board This problem was certainly not anything one would normally think of. I'll happily share the solution with the forum, just wanted to make it more interesting

Let's have a try.

It must be something not fuel related since you haven't thought of it and the carbs were your guess. Is it an electrical problem, like a failure of the voltage regulator when it gets hot?

Dirk

AoS hat geschrieben:Let's have a try.

It must be something not fuel related since you haven't thought of it and the carbs were your guess. Is it an electrical problem, like a failure of the voltage regulator when it gets hot?

Dirk

Hi Dirk,
It wasn't an electrical problem and not really a fueling issue.

Do you guys give up yet

Okay, another try. Mice living in the airbox?

Dirk,
hopelessly lost and hoping that others have a better guess. Where are the English speaking people?

AoS hat geschrieben:Okay, another try. Mice living in the airbox?

Dirk,
hopelessly lost and hoping that others have a better guess. Where are the Englsich speaking people?

I can tell you that there were no animals of any kind involved.

Hi,
I had a similar behavior after reassembling the carburetor. It was caused by a leakage in the vacuum system, unfortunately I forgot to attach the vacuum hose to the fuel tab.

Greetings
Manuel

TOOL hat geschrieben:Hi,
I had a similar behavior after reassembling the carburetor. It was caused by a leakage in the vacuum system, unfortunately I forgot to attach the vacuum hose to the fuel tab.

Greetings
Manuel

I can confirm that all the reassembly was in my case was done correctly, nothing missing or left off.

<delurk>

Dodgy rectifier?
(going for the really unlikely here...)

Acacius hat geschrieben:<delurk>

Dodgy rectifier?
(going for the really unlikely here...)

Sorry, but wrong

Guys let me know if you give up and want the answer.

Maybe a lack of valve clearance will prevent valve closure causing leakage?

Brummbär hat geschrieben:Maybe a lack of valve clearance will prevent valve closure causing leakage?

Nope, the valves were not the problem.

I give up.

Dirk

Not an electrical or air problem, no leakage, fuel system, valves, jets ok and regular assembled. So the last thing I can imagine is the exhaust system. Maybe some insulation material has blocked the silencer? If not I'm out too.

Manuel

OK, guys, here is the answer. I know it sounds hard to believe, and this is why I never even thought of changing the oil. I did look at the sight glass and the oil looked ok, i.e. not frothy or milky, but then again this bike does not have a water cooling system so should not have expected to see water in the oil

This is how (translated from Japanese) the mechanic explained it:
- Gasoline was mixing in the engine by overflow of a carburetor
- 3.5 liters came out from the oil drain plug, the XF takes 2300ml (as we all know)
- When the engine get warm, the gasoline mixed with oil will evaporate and it will enter into the air cleaner box via the breather system. When this happens the AFR will become too rich and the engine will not idle, but revs out ok though.
- The carb overhaul I did fixed the overflow so no more (or not more than acceptable) gas mixes into the oil.

Personally I would have expected the gas to evaporate eventually (and fix the problem), but maybe (obviously) there was enough there that would have required much longer riding/evaporation time. Remember, the bike idled fine when cold... Also, the plug didn't look too bad, my bike has an after market pipe so always runs a bit rich...

Oh well live and learn