Pinging

[ReconMedic]

I have noticed recently that this thing is pinging at (guessing no tach) 4.5k+ when UNDER LOAD OR JUST BEGINNING TO EASE OFF THE THROTTLE.
At first I thought Lifter? Valvetrain? But then I thought maybe a tank of crappy gas. I filled it with sunoco 112 and it seemed to get better, but not really. Then I thought, Vacume leak so I pulled the carb, retightened intake and sealed the carb real nice. Still doing it.

I did notice that I was a damn QUART low on oil so I expect that it may have been the problem, just added a quart and havent ridden it yet. But I just pulled the plugs and

If its running too lean, how adjustable is the carb? One jet for the entire range or is there a low and hi cfm side to tweak?

 

[ReconMedic]

oops, to finish my sentance from above....I just pulled the plugs and they appear clean but light and a bit chalky looking. This is a lean condition yes? The pic really doesnt capture the dry whitish look too well, anyway, any thoughts on my next step? Obviously if adding the oil stops the pinging thats fixed, but if not, or even if it does, shouldn't I richen it up a bit?

 

[ReconMedic]

ok, I rode it and it really seems to only occur at high vacume and hi rpm, like the timing advances too far or something. definately related to throttle position though because at 95 mph it will start to ping and if i pump the throttle it might stop completely for minute.

 

[IYAOYAS]

What year is your bike? You can not jet a fuel injected bike, you will need a map.

 

[ReconMedic]

98 cv carb, not sure if I can adjust the needle a little higher or if I just need the jet kit.

 

[jimijeans]

Hey are you talking about a 1998 tuber model bike .The plugs look just (slightly)lean.check the carb. adj.,and check your timing. Is the Bike New to you? I would check all the small stuff first. The Sunoco here only carries 105. So I go to a race shop for 110 octane and mix it. The timing is hopefully all it is. post up let us know.Welcome to the forum.

 

[ReconMedic]

Im swapping out the 180 jet for the next size up, that might be enough to deal with it. I'll go from there.

 

[ReconMedic]

ok 190 jet in and also went to an 8 from a 7 plug in case the plug was too hot...still pings but with less intensity per occurance. It will not do it under full wide open throttle, makes me wonder if my mid jet is the issue and its leaning out during the transition to the main jet.If not, the only thing left is timing? Don't know jack about doing a timing adjustment on this thing. you just turn the magnito like a distributor or what? And what about a timing mark so you can use a lite??

 

[ReconMedic]

More on the subject, after dropping my gear ratio with the 23/55 sprocket combo, I see that the bike doesnt need to be at wide open throttle to acheive top speed .. meaning that I run out of gear before I run out of throttle, at full throttle I WILL over rev the engine in top gear. Therefore, I might be running on the primary little jet more than the main jet during higher speeds..perhaps this is why its still a bit lean at higher rpm causing the detonation. Thats my current theory, so my next step is to up the small jet one size before I mess with timing. My new plugs were still too light after going to the 190, thats what made me think of this.

 

[jimijeans]

Might want to put some miles(120)or so to see if the plugs still look the same. The timing If it was my bike adj. only 1 or at most 2 deg.,then ride, mark your current setting before you do.You are on the right track. The X1s and a few other carb model engines some run a little lean. What size jets are in it? Too rich, on a cold start it will flood all the time.Buell model bike you have does run out of gear(unless some Tranny work is done)before you run out of Throttle.Changing the sprockets will Help(depends on what you are wanting) top speed OR good midrange. The orignal stock sprockets are pretty good for everyday riding. The timing and carb,verus/the jets is key to the pinging. Small steps,post a pict of the bike when can.I would find a manual on the bike if possible.It will have some info on carbs and other areas needed now and then. Take your time it will come together. ~Jimi

 

[ReconMedic]

 

[ReconMedic]

ok, I yanked the 42 and replaced it with a 45. I played with the mixture for a few rides and it runs better than ever and zero detonation/preignition. So there it is, a 190 main jet and a 45 slow jet and it idles perfect and pulls hard as hell. BIG IMPROVEMENT and no ping!

still planning on changing out the 55 sprocket, maybe a 49-52 need top speed too.