If anyone can shine a light on the following I would be eternally grateful. A2 model
Going back 3 years, Problem starting the bike. Fitted new plugs, when it did start, very sooty after 40 mile run, and you could feel the bike starting to die . Excessive smell of unburnt fuel.
Bottom air box filling with fuel. Sparks at plugs never looked good ! Voltage only 12.5 V @4000 RPM.
So now this is what I did over the last 3 years, to address these problems-
Float Levels, adjusted using tube gauges to correct levels (not overflowing now)
Pingle tap / petcock fitted
New stator fitted, now reading over 14 volts @ 4000 rpm
new sets of spark plugs fitted, all of the following tested.
ND W16 EPR-U (Hot set)
ND W20EP-U (none resistor type)
Main jets standard.
Could this be Coils ? and would I benefit from a set of Dyna s coils but £350 !
Would Pilot air screw have anything to do with this ? or would it be just for that first 1000 rpm ?
Could this be the needle hight ? and would it cause this much of a problem ?
So after all that, Still no improvement. Plugs still sooting up after a 40 mile run !!! The HOT set, ever so slightly better, but still sooting up !
I just Can't give up on this Bike as it's the best Bike i have ever owned, well it would be if I could sort these issues out. I'm the wrong side of 60 now ! so time is running out.
I would like to think I have a few years of riding on this bike, So any help would be great.
Black sooty plugs- over fueled. You seem to have checked the common issues and yet you still have a big problem. Some further checks you should do before going down another avenue are
check the choke plungers and ensure they are fully seated.
Inspect the enrichening circuit and ensure those plungers are also fully seated. Better still, do the enrichening circuit delete mod as suggested by Scotch. That will eliminate one possible issue for sure.
Never forget that low compression will also show up with sooty plugs since the fuel mixture isn't burning properly. Anything below 100 psi compression should be addressed.
I guess it all depends. I'll assume that you're not the original owner so many things could be off. If, when you go to check the needles, they should be in the middle slot. People have tried all sorts of combinations but the best combo is needles in the middle slot and stock main jets.
Another maybe not so obvious check that seems to escape most is the mechanical timing advance. If it's not free and lubricated with a light coating of lithium grease, that too could be part of the cause.
I recall the use of hot plugs mentioned. That's a no no in my books. Back in the 70's it was a common practice to install hot plugs to burn off oil residue on spark plugs in engines drinking a lot of oil rather than doing piston rings or valve stem seals. A Band-Aid cure at best. The consequence is possible preignition and blowing holes in your pistons.
Black soot is not oil related.
Many thanks again for that. I've only owned the Bike about 10 years. I was not lucky enough to have one of these brilliant machines when they where new, I could only dream about it then.
The Mechanical timing advance ! i better check this out