Motor running Lean.

Something else to think about is that your crank phasing isn't necessarily spot on, there've been several reports here about hydraulic locks twisting the crank but the bike still seems to run the same as usual. Be sure to check for TDC on all 3 cylinders, not just cylinder no.1. Assuming that the crank is dead true can throw your ignition timing off by quite a few degrees.

If your crank phasing is off (if TDC on no. 3 is different from no. 1, or if no. 2 is not EXACTLY 180 different from 1 or 3), there is a small adjusting screw that you can access under the ... sorry, no there isn't ::), you have to pull the engine out, split the crankcases, pull the crankshaft out and have somebody who knows what they're doing pound it back into phase.

Ken
 
Modern fuels are tough to read. Modern spark plugs, well nothing has changed. Start with your ignition timing. A flat curve works best with a HC engine. Get it free from any signs of detonation (ping) on the plugs..then refine the jetting...then refine the heat range on the plugs...then refine the timing..then refine your plug heat range..then re-refine the jetting. Start with timing first.

Plugs should be very clean in appearance for some time running in an engine correctly jetted and not burning oil. I's a myth that they need to be brown. The mixture mark is very low inside the bottom of the porcelain. Champion used to make a very cool spark plug reader, a light with a magnifying glass. Very helpful, and really needed to read plugs. Someone still makes them, somewhere. Use one if you can.

Gordon Jennings wrote this 30 years ago, still good advice.

http://www.strappe.com/plugs.html

Rusty

27*
 
Grant said:
After a nightmare time with Champions I will NEVER use them in a triple engine again. Straight out of the box they were faulty, leading me to suspect all sorts of other equipment.
I thought "well it can't be the plugs, they are brand new". This was not one incident, or all 3 plugs at once.
Click to expand...

Grant,

Many, many moons ago, I had exactly the same issue with a NGK.  Pushed the bloody Bantam around the block at least 5 times before I swapped the new NGK with the old, rotty KLG it was meant to replace...... instant life! :P

NO F*******  WAY I will ever fit a NGK to any of my bikes...... although I have sold quite a few thousand without the slightest issue! :o

I'm quite happy to use the much maligned Champions, NOS Gold-Palladium types come up cheap at autojumbles, about ?1/ea. instead of ?20 retail. :D

piet
 
Not to get wrapped up in plug issues but when I fitted new NGK plugs to the Sprint I found out one of the brand new ones was a complete dud,I m still on NGKS but I was surprised never had that before.

Shaun
 
hi
had a champion plug once ,straight out of box,had no thread machined on it,it got through quality control some how,good point was it will last forever and never foul up
neale
 
Magneti marelli plugs are the most spectacular ones I have found.
It was a car application, bump in bonnet then dropped a cylinder.
The whole core of plug still attached to HT lead, collar still in engine.
Supplier said "they fit these in Ferraris" Nuff said.

 
I must say that my bikes are totally ignorant to the brand of spark plug - since I changed from Dell'Orto to Keihins! Never had ONE fooled plug ever since! I had NGK, Bosch, Campion - no difference to be honest. And what I also changed is never to engage Choke fully. I always start the bike with half choke. If it does not start, I gentle give a bit more until it fires up.
 
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