Oil useage getting silly

[mr blackstock]

Hello all,

I am hoping someone might be able to help with some of the multitude of problems I am having.   My bike is a 1984 FJ1100, 3mm oversize pistons with rebored cylinders, mild lumpy cam.

The bike is using too much in my opinion, I top it up to the recommended level, and 150 to 200kms later it is half way down the sight glass.  The plugs are dark to light tan, not oily, no smoke from the exhaust, no leaks from the engine, crankcase vent runs to a filter not carb intake. The engine seems to run very hot IMO, to the point the petrol tank warms up a fair bit.  I do mostly highway riding, and admitedly the climate temperature is around 26 to 36 degrees centigrade.  I use a good brand of oil, Catrol activ 4T 15W-50, non synthetic.

The oil cooler seems to warm up with the engine, so I am assuming oil is circulating, should I clean it out? or install a larger one?

As an aside, I am having odd carb probs, they are balanced, but it seems like one is racing up the revs and I need to rev the bike a little to get them down, but then will creep up again.  Also there is popping from either number 1 or 2 pots.  The idle jets are 2 turns out, needles set to the middle notch.  I know the response will be "air leak" but buggered if I know where!?  The carbs were cleaned, new valve seats, new "O" rings on the rubber mounts with some gasket goo of correct temp range.  New plugs, proper gap.

And the bike exhaust smells of petrol on idle.  I hope someone can give me some pointers?

I won't go into the electrical problems I am having, could the coils be my issue?

The old XJ650 in the corner of the shed is looking more attractive every FJ tear down....

cheers, Gareth

[Mark Olson]

If you are running rich it will wash the rings and consume oil . what is your mpg?

weak spark will do it too.

[RichBaker]

Leaky float needles, maybe?  If the exhaust smells rich, I agree, the excess fuel could be washing the cylinderwalls...

[Horse]

This won't help you but, my 94 had 58,000 on it when i got it & it used about 500ml a week  I thought i bought a lem. so i just thrashed it for a week or two & it now dosen't use a drop beetween oil changes GO FIGURE !!! My carbs will sometimes leak on the side stand when i park (NOT OFFTEN ) Yes it dose need new needles & seats, & it's also fuely on statup !!! But it don't use oil .... Has it been recently rebuilt   My rebuilt XJ 900 used oil for awile after the build then settled down.. the other guys could be on to it though 

[mr blackstock]

Thanks for the replies.

If you are running rich it will wash the rings and consume oil . what is your mpg?

weak spark will do it too.

The miles per gallon are around 180 miles to 6 gallons?  or I get around 250kms to a tank highway riding.  I also did the coil conversion thing, running them straight from the battery.  I think the consumption of fuel is high, but the bike is now around 1200cc, give or take with 3mm oversize pistons, and has a lumpy cam so maybe that is normal mileage for that engine?

Leaky float needles, maybe?  If the exhaust smells rich, I agree, the excess fuel could be washing the cylinderwalls...

The float valves are good, two new ones and no fuel leaks, and the plugs are a decent colour, and the exhaust is clear, no smoke, no colour.

The bike was rebuilt around 5 years ago with the oversize pistons, ridden for around 5000k, then parked up until recently.  I suspected valve stem seals, but the oil has to go somewhere...

Not sure what to do.

[Harvy]

250 Kms to a tank seems quite rich to me.
My 1200 is stock at 1188cc and I can comfortably get 350....even with dual pods and 4-1 exhaust and appropriate jetting.
B4 I replaced emulsion tubes and needles, I was down around the 300 mark and it was rich!. Running a finger over the inside of the exhaust can will confirm that......if it is black and thick.

Harvy

[andyb]

Depends on the use to me.  Black deposits on the pipe tell me that you use the choke to warm the bike, y`know?  Not a substitute for reading the plugs themselves (as the plugs get hot enough to clean themselves off, where the pipe does not).