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Spark plugs white ? fz 600 86'

travgag

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Hey guys, so up here in Ontario spring came early ! fz 600 86'

I took the bike out twice for about 150 klms, and noticed there's like a powerband at 4 k but remeber it being like that last year ( first year i got it)
I was going to change the plugs, so i pulled the plugs off and they seamed to white to me, check them out, and thoughts ? the whiter ones were frmo the outer cylinders, the one center one seams nice to me, i cleaned the carbs last year but i will again, which got me thinking is there a fuel filter on the bike ? there's a metal one in the tank correct ?

also the plugs for spec are Cr9E or Cr8e and the ones that are in it when i got it are DR8EA,
I couldnt find CR9

thanks guys

bike1.jpg

bike2.jpg

bike3.jpg

bike4.jpg
 
I'd say somewhere between the light choc brown one and white is good. More towards the white. The balls are deposits which isn't uncommon. Q? Do you ever hear it ping or detonate while taking off? Those could be lean and be piston transfer from detonation.

Now that other one is not so great. It appears to be oil covered. Either valve stem seals or rings leaking.

You might do a compression test and see where it stands. Does it blow a blue cloud on occasion? It wouldn't be much just a light haze. Change the oil often and it won't hurt.

Tell us what you find after a compression test. . . .
 
Hey yea so they're okay, I cleaned the carbs, and very clean, and then checked compression and 120, 118,110, 120 the one that was darkest was 110, reason being ( i think) the carb boot behind the carb was leaking bad, it was folded inside, maybe il do a ring job durring next winter, i dont like the one cylinder being that low, its a little to low

does'nt blow to much smoke, nothing extremly noticable, burns slightly a bit of oil, i changed it at the start of last season and also at the start of this season, whats the mileage per change ? i did 8 000 k last season, a car is 5 000 k

thanks !
 
I was just reading and i didnt check compression with the throttle full, but i did have all 4 plugs out, and i just learnt about the oil in cylinder to check if its rings or valves, sounds like a good test,

check what these guys are talking about

XJBikes.com › Forums › XJBikes Talk › XJ Chat › Compression test PSI on FJ/FZ 600 motor?

whats the compression supposed to be like ? my car was 160 from what i remeber/ the bike is a 12 - 1 ratio does that mean 12 times atm,

according to my claculations atm is 102 kilopascals, x 12 x 0.14504k/psi = 177 psi of compression

ahha,

anyways
 
You have a 26 year old motorcycle, none of the plugs look all that bad and the compression difference between the cylinders is more then acceptable and three cylinders are pretty much equal.

I would say just ride it and enjoy it the way it is. Save some money and in a few years buy something newer.
 
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I rarely follow plug charts like that. They can be a bit of a guide but thats it.
Depending on where you get your fuel and the additives they use, the look of your plugs can easily different from those pics.
Also, depending on when you take plug readings, the color can change. For instance, if you have a rich idle condition, but read the plugs just after doing highway speeds, your reading will not reflect this accurately.
Plug chops must be done in a minimum 2 steps, idle and high speed.
After all, carbs have a low speed circuit and a high speed.
On my CB, if my plugs looked like your inner cylinders, That would be too rich.

When I tune a carbed bike, unless it is a really old style slide carb, I shoot for a very light tan to a light tan.

Also, when doing a comp test, did you use a small hose or steel line?
A standard comp tester is built for a car and those pistons move a lot more air than a little 600 does. As such, those testers will not give an accurate reading. You need a to use a smaller I.D. line for best results.
 
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