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bikereurope 5 Aug 2012 11:35

spark plug diagnosis
 
1 Attachment(s)
i changed my spark plug today. 1500-2000 km since last/1 year.

how would you say this plug looks?

the bike has been a bit difficult to start lately (kick).

i feel there might be some unburned fuel when i release the trottle, it doesn't go "bang" in the exhaust, but it rumbles a bit.

last time i changed plug the plug wasn't white at the tip as this one is. The picture may lie a bit, its not completely white, but grayish.

bikereurope 5 Aug 2012 11:35

the plug is altso a bit rusty on the outer parts

bikereurope 5 Aug 2012 12:23

1 Attachment(s)
better pic

Zergman 5 Aug 2012 12:47

Looks like it's running too rich on the fuel to air ratio. Spark plug should be gray-ish color, kinda like the color of the sand.

*Touring Ted* 5 Aug 2012 16:41

Is it the correct heat range for your bike/climate/altitude etc ?

backofbeyond 5 Aug 2012 16:54

Have a look at this link - How you can read spark plugs and select them - by Gordon Jennings. It was written by an American journalist and published back in the late 70's but it's just as relevant today. There's such a lot of info there that by the time you get to the end of it you'll probably be able to read next week's lottery numbers from the distribution of soot on your plugs. :D

bikereurope 5 Aug 2012 19:20

Quote:

Originally Posted by *Touring Ted* (Post 388322)
Is it the correct heat range for your bike/climate/altitude etc ?

im not shire what you mean here?

i haven't adjusted the carburetor before, is it straight forward to adjust the air/gas ?

*Touring Ted* 5 Aug 2012 20:04

Quote:

Originally Posted by bikereurope (Post 388335)
im not shire what you mean here?

i haven't adjusted the carburetor before, is it straight forward to adjust the air/gas ?

Spark Plugs 101: Understanding Spark Plug Heat Range - SummitRacing.com


Before you think about jetting... Is it running okay ? Is it popping or does it feel hesitant to rev up ?

Have you changed your exhaust/airbox/filter etc ??

Are you valve clearances okay ?

bikereurope 5 Aug 2012 20:14

haven't changed anything.

it runs great. i think its using some oil, its difficult to read the levels correctly on the bike. i have done the procedures that is recommended on the hubb. is it possible that the oil doesn't flow back up to the "oil tank"as good as it should?

but. the bike runs great. no popping, but maby a "rumble" when i get off the trottle...

its a kick, and lately it has been harder to kickstart when cold.

*Touring Ted* 5 Aug 2012 20:25

Quote:

Originally Posted by bikereurope (Post 388339)
haven't changed anything.

it runs great. i think its using some oil, its difficult to read the levels correctly on the bike. i have done the procedures that is recommended on the hubb. is it possible that the oil doesn't flow back up to the "oil tank"as good as it should?

but. the bike runs great. no popping, but maby a "rumble" when i get off the trottle...

its a kick, and lately it has been harder to kickstart when cold.

Check your valve clearances... Very easy to check and adjust on an XT600.

bikereurope 5 Aug 2012 20:39

ok, they were checked 2500 km ago by last owner...

*Touring Ted* 5 Aug 2012 20:47

Quote:

Originally Posted by bikereurope (Post 388344)
ok, they were checked 2500 km ago by last owner...

Any white/blue smoke when running or at start up ? You say it's burning oil.

bikereurope 5 Aug 2012 20:58

some smoke when starting. stops after 200 meters. valve seals maby or to much oil...

*Touring Ted* 5 Aug 2012 21:14

Quote:

Originally Posted by bikereurope (Post 388349)
some smoke when starting. stops after 200 meters. valve seals maby or to much oil...

If an engine always smokes it's a sign of head gasket/badly leaking valves, piston rings etc.

If it's just on start up it's usually a weeping valve seal..

That's assuming you're SURE it's oil smoke.

Mezo 7 Aug 2012 02:40

The only reliable way of reading a spark plug is by doing a "Plug Chop"

Google it.

Mezo.


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