XTIAN BIKE UPDATE????

[AussiXS11G]

thats nuts....
seen this?
http://www.ngk.com.au/spark-plugs/technical-information/spark-plug-analysis

[excess.11]

From memory.....no....they seemed relatively ok.
No excessive fouling......or any oil on them at all that i could see.

[AussiXS11G]

what did the plugs look like?
black, and wet I am guessing...
seen this?
http://www.ngk.com.au/spark-plugs/technical-information/spark-plug-analysis

[excess.11]

Was it 3.5 liberal litres?..........or less than 100ml ?
I d like to see some 3 litres of oil being  poured back  out of the exhaust ...
......that would be the definative answer as to whether it was pumped out and held in the exhaust.............
.....or it simply was nt there in the first place at the time of failure.......

[melbxs]

There was definitely a liberal splash of oil down the back of the crankcases. I reckon EVs explanation sounds very plausible.

[excess.11]

After reading the article i posted a little while regarding plug chopping..............

http://kawtriple.com/mraxl/carb/plugchop.htm

I m thinking unless you perform the test as they describe...........trying to read these is like reading tea leaves .

[AussiXS11G]

Are you fellows all using BP6ES plugs?
I have been using 7's .....these are the plugs out of mine after Bourke...they have been sitting on the bench for a while and I don't remember the which cylinders they are from...

[excess.11]

Can someone ask Mal to upend the exhaust and pour all that oil back into a container?
I d love to see that pic....

Also........there was absolutely no compression on 2 other pistons....what was the verdict on those ?

[XSIIE]

Jonesy,

I just cut an pasted the relevent info from your reply.

Green dynatek coils - yes
BP6ES plugs? - yes
Same fuel - yes
Same speeds and similar loads - I am a fat bastard
State of tune ? Mine was found to be out of balance and running rich (thanks Dale for the colour tuneup).

The same thing happened to me on an XS 650 about 30 years ago where I holed a piston, although I had a big smoke screen along the Tullamarine Fwy to St Albans (Vic).
 It still ran (Just) on one cylinder. (slowly)

Eddy

[Eveready1100]

#2 attempt at answering Jeff's Q's

On the fuel being an off blend..........any vehicles i ve owned.......... if not suitable for ethanol............run like shit before i even get out of the servo...........

Due to good management, I've never let that Shite anywhere near my XS. i have in the past tried running it in my GPZ 750 where i was trying to save a buck, but the bike ran sluggishly and chewed a lot of fuel compared to running the real stuff. I have on occasions had to put some in my wife's Astra which also drove reasonably but was obviously down on power and economy suffered badly, which to me , at least, you need to run the fuel settings richer to get the same perfomance out of your motor. likewise, that means a lean running condition if left untouched.

Regarding the colourtune........if you don t get that right...........then trying to synch the carbys is like paddling upstream in a barbed wire canoe.

colourtuning has only come on very recently. Till it's invention, we all relied on the old tweaking of the mixture screws, synch carbs, then take it for a run to see if you got it right. It's now an exact science due to that gadget

On the subject of the piston becoming a big pressure pump.......i would of thought instant pressurization of the crankcase would of resulted in oil being forced out through areas such as the breather pipe.

With the absence of a piston crown, the oil would be pumped straight through the exhaust valves as that would be the easiest exit for the pressure. Maybe a little to the airbox, but this would happen very suddenly easily despatching a couple of litres in seconds at the engine speeds run at the time.

And for Xtian. If you are stuck for getting pistons etc, my spare bike has 56,ooo original klms on it. If you would like the pistons, rings & barrels, you are welcome to them. I know they're not brand new, but if you are stuck, let me know.
I was saving them for a rainy day, but mate, it's been pissing down on you recently.

[Jonesy]

I can tick a couple of boxes to compare with Christian
Green dynatek coils tick
BP6ES plugs?
Same fuel
Same speeds and similar loads
State of tune ? Mine was found to be out of balance.
Can verify that following him towards the end Christian would at times disappear behind a smoke screen So Errols theory of pipes full of oil could be on the money?
as for the low oil and getting hot theary in point No2.  I'd suggest it'd take out the bore and rings first.

There ya go 2 bob in the coffers

[excess.11]

It would be interesting to know.......what voltage differences.... if any........ there are between the secondary coils on both the standard and dynatec units.

The only thing reported on failure was a puff of smoke.........which is understandable.
Out of interest..................
I d love to know where 3.5 litres of oil went.......all at once!

Thats a LOT of oil...........

On the fuel being an off blend..........any vehicles i ve owned.......... if not suitable for ethanol............run like shit before i even get out of the servo...........
Drain the tank or refill as soon as possible........and back to normal running order.

Happened once to me on my XS1100......and once to me in a van i have.........they kick and splutter almost immediately.

Regarding the colourtune........if you don t get that right...........then trying to synch the carbys is like paddling upstream in a barbed wire canoe.
Were the carbys set up too lean?

On the subject of the piston becoming a big pressure pump.......i would of thought instant pressurization of the crankcase would of resulted in oil being forced out through areas such as the breather pipe.

Maybe......... there were no signs............because....there was no oil...

Again.....no reported oil within the air filter or signs of it expelling anywhere else.

There are reports of excessive oil......being burnt .

[Eveready1100]

Ok, Jeff. I'll have 1st crack at answering a few of your Q's.

The colourtuning of the carbs only effects the idle circuit of them. The mixture in the upper registers is controlled by the slide needles until full throttle is applied where the main jets take over completely. It is the slide needles interaction with the main jets that give the air / fuel mixture for most of the engines operation. The only ways to truly check on the mixture settings are plug chops and by an exhaust gas analyser to be precise. However, just checking  the plugs colour after running is a good general indicator to mixture ratio.

The type of coils used shouldn't have much effect on the temperature of the spark. They only serve to supply a healthier spark in the case that the old coils weren't working properly. The only thing that would cause grief here if one made big changes like going from the BP6ES plugs to maybe a 4, or lower which could cause problems then.

As for the other bikes being unaffected by the fuel, it all comes down to the individual tuning of the motors to say how much it would affect them. If it does turn out to be the case of a rich dose of Ethanol (POISON to our XS's), there may have been no outward signs of trouble at all, other than maybe slightly more throttle to accelerate the same, but if the combustion chambers are nice and clean, which they would have been after the good running up to that point, there may have been no glowing hot spots to promote pinging or detonation. Just getting slowly hotter and hotter until one piston top caved in. ( maybe one slightly flawed piston crown at first?)
From that point, that jug has turned into a big compressor (pump) and will suck a lot of oil out in a short period. Meanwhile, Christian has tried to compensate for the misfire by rolling the throttle open a bit more hopeful that the plug will clear but in turn makes the other pistons follow suit till it will run no more.
As far as the lack of outward evidence of the oils exit from the motor, there could still be a lot of it in the pipes depending on the mufflers inner shape. I don't know if the system has been hung up on end since it's been removed. That could be interesting to hear.

As far as Bryan's bike is concerned. I'd say that the modifications he's done to the head, cams, coils, carbs  and the pipe have a lot to do with how efficient his bike is at speed which is where it is now happiest at. Plus it is a much fresher engine than Xtians.

I'd say that Christian's right. Just unlucky that the bikes number had come up.

[AussiXS11G]

nearly makes me want to pop the head off mine and examine it closely......

[Christian Raith]

A couple of points
Colortuned ok and balanced ok.
The Coils and ignition have been installed for about 5 or 6 years and the carbs about the same.
Did quite a few ks with no problems??
Just think father fate was not smiling on me or like us just had it's time??
And I thought it only came in three's