I'll add that I checked compression the 2nd or 3rd time I had it running and it was:

Cylinder 1: 150 psi
Cylinder 2: 135 psi
Cylinder 3: 140 psi
Cylinder 4: 140 psi

Bike is a barn find I got in September. I'm told last time it ran was 15+ years ago. I've been going through it and got it running a few times but it smokes a lot and I'd like to know why it might be smoking. This is the 3rd or 4th time I've had it running and it's smoked each time. I guess the carbs are not set exactly right because I had a little fuel coming out from the fuel overflow sometimes and I was getting a slight backfire from the carb intake once in a while which seemed to come from the carbs that were pushing fuel through the fuel overflow. Link below for video of today's smoke session. To me the smoke seems sort of grey or grey/white. It's definitely not black. The smoke seems to intensify when I rev the engine rather than go away.

https://www.youtube.com/watch?v=BkKfJiQ6wn8

1986 FJ1200
20k Miles
Single Inlet Carbs (hooked up to a small plastic bottle)
115 Mains
155 Air Bleed
40 Pilot
The little needs under the carb floats are sized for single inlet carbs since the carbs were originally built for a Legend car. I figure for my driveway sessions this should be ok.
Stock Headers and collector with Cobra F1r Slipons
Uni Pod Air Filters
New Spark Plugs
New 10w-40 Synthetic Motorcycle Oil with about 5% Marvel Mystery Oil


I'd like to keep the bike and get it ridable but want to make sure I don't have a money pit. Exhaust smoke aside it still needs new clutch slave, clutch lines, brake caliper rebuilds, brake lines, sprockets, chain, tires and the stock gas tank is filled with rust so I either deal with that or I also have a 91 fuel pump tank which is clean inside but then I need to convert my gravity fed bike over to fuel pump. So There is considerable time and money ($1500-$2000/) involved to get the bike in running order and I'm not sure if it's worth doing all that if it needs something major like piston rings or valve seals. I don't know how to do internal engine work so that's either another cost for me to send it to RPM all the way from NJ or I try to do it myself and hopefully don't botch it.

Looking for help diagnosing the smoke and for opinions if bike is worth continuing to get running and can be ridable or if I should cut my losses and sell it or part it out and put that $ towards something newer?

I understand now and corrected it thanks for the help

i had bad noises in engine to and also have converted to the xjr 1250  short oil jet nozzle while in there. I think you can replace the oiljetnossle with out splitting the engine. you can also replace the camchain with a chain with masterlink .i did that once https://fjowners.com/index.php?topic=18143.210   you should also check your camchain tensioner first .

great sport tour/ many extras included. 20k miles

Good day everyone !

A friend of mine gave me his father's FJ1200 to put it back on the road. The man passed away more than 20years ago and the bike has not started since. It's a "1WH" model (it's french, so maybe there are some differences with the US ones).

Here is my problem : cylinders 2 & 3 get a weak spark, cylinders 1 & 4 get no spark at all.

When I turn the key, the right coil (1 & 3) receives 11.3 volts, and the left one only gets 0.53 volts.
For that reason, I don't think changing the coils alone will solve the issue yet.

The left coil is wired with an orange cable (shared with the right coil) to the ignitor box, and to the main relay with a red and white cable. The latter seems visually in good condition so I suspect that the relay is bad.

Anybody knows how to test that relay ?
What wiring connections would you check ? (in case I forgot one)
Any chance some other system/sensor is interfering with the signal ? (like the fuel reserve for example)


Thanks in advance for your help ! 

PS :
The battery is new and puts out about 13v
I tested the coil's power supply with the coils disconnected.
The big ground cable at the back of the engine is clean and corrosion-free

Thanks again.  I did find a thread which suggests removing the alternator (generator?)  Maybe that is the solution.

https://fjowners.com/index.php?msg=203343

I don't know - maybe Robert or Randy has a trick without splitting the cases?   

Thanks very much!  Figures I just placed an order with RPM.  Is it a significant tear down to install this part?

Problem could be enough slack in the starter chain to slap the starter clutch oil nozzle. 

This nozzle is designed to prevent that

https://www.rpmracingca.com/proddetail.asp?prod=UpgradedOilNozzle