TE/TC Hearing detonation in front of motor

[HS507]

I own a 2016 te300. I switched to JD kit 38pj and blue needle, 700ft elevation 72-90 degrees out and sometimes i can hear a detonation or knock near front of motor i think, when throttle is on first third, just once in a while,not every ride. Im at 1.5 turns out on air screw, little spooge and plug looks dark to black but not too rich. To me its a hair on rich side so why a knock? Im using green spring now but yellow it acted same way. Any ideas guys? I will call JD in morning.

 

[Tetley]

It may be the idle is rich and main jet is rich, giving rich plug colour, but the needle is lean. I'd try raising the needle by a clip.

 

[HS507]

Ok. Think i saw your videos on utube?

 

[Up-tite]

Power Valve rattle?
Check linkage is not loose.
Later George

 

[HS507]

Brand new bike. I will check but doubt it

 

[Norman Foley]

Detonation... What the KTM guys call "Pipe Bang". Try following Tetley's advice.

 

[HS507]

I will

 

[Michael Ryan]

interesting as the "blue needle " is richer than the red . Does the bike bog slightly at 1/4 to 3/4 throttle movements....can be an indication of a lean condition.
Your definitely not lean on your pilot. As Tetley said, dropping the clip will allow more fuel and cure a "lean condition" if its within this throttle range.
I have had a few JD kits and generally found them to be a tad "rich" so will be surprised if its the needle

 

[HS507]

After talking with jd jetting im not convinced its lean either, but yes these symptoms can sometimes be a lean condition. It seemed to happen after i put green spring in PV.

 

[racemx904]

Premium fuel?

 

[HS507]

Always yes sir

 

[HS507]

I mislead by saying it started when i put spring in pv, im getting my other issue confused with this post, sorry guys. My knock has happened at differing temps and usually riding along in 2-3rd gear with normal throttle operation. Im thinking its a rich detonation, just build up by my riding style

 

[lankydoug]

I had a similar problem with my 09 wr250 when it was new. I was using 93 no ethanol and when the bike was jetted crisp and clean it would knock just as the throttle was cracked under a load. I could go up one step on the pilot and it would never do it but it would run rich and load up trying to foul the plug. I switched to race fuel and went back to the crisp jetting and never another problem. If you are having this problem on the needle circuit 1/8 to 3/4 throttle then raise the needle one notch and see what happens. If it doesn't knock but is too rich it could be poor fuel. Also it can be lean on one circuit and rich on another so pay attention to the exact throttle position when you are trying to figure out what to change.

 

[racemx904]

Rich denotation?

Are you sure your not just lugging down so low in RPM that it just cant keep up..... Sounds like you just need to downshift....

 

[HS507]

Haha yes from what i hear if you ride mildly it cant load up but im not sure if this exosts, sounds damn fine though.
Yes it could be that i need to pay close attention to throttle position. Jd said play with air screw first. It doesnt happen all the time or sound like a bunch of marbles (lean) knock, just once in a while. I will pay attention closer, all good advice guys thanks!!

 

[lankydoug]

Rich denotation?

Are you sure your not just lugging down so low in RPM that it just cant keep up..... Sounds like you just need to downshift....

Ha Ha yea, it won't detonate while rich but it can be lean on the needle and rich on the pilot and lean knock at 1/4 throttle but foul plugs on the pilot at 1/16-1/8 throttle. The point I'm trying to get across is if the fuel is crap pump gas you can't always jet it perfect without the fuel detonating but you can go rich and prevent knocking put it is giving up performance.

 

[HS507]

Yes rich is safe, i have just a little sppoge and im using jd jet to the recommended setting. 38pj, blue needle and main recommended. Yes a possibility crap gas. My gas always gets stabil no matter. I will put half tank of fresh with existing and keep documenting things. Rich detination.. Haha, i might have coined a phrase

 

[BSBen]

Please keep us (me) updated. I have what sounds like a similar situation. I'm not convinced it's detonation, although it's possible.

 

[HS507]

Please keep us (me) updated. I have what sounds like a similar situation. I'm not convinced it's detonation, although it's possible.

Ok, like i said 162mj red needle 4th and 38pj, i moved AS out to 2 and added 20% Dragon Race fuel (true 95oct R+M/2) to tank and its gone. Not sure if it needed higher octane or more air. Dealer said if its a bit rich it can reignite, also alcohol is in fiel now days and doesnt mix well with oil so could leave unburt fuel on sides of head to reignite, could be pre ignition too. Im using br7 plug, i think its hotter than br8, nit sure if it helps or hurts. Still learning i guess bro

 

[lankydoug]

Ok, like i said 162mj red needle 4th and 38pj, i moved AS out to 2 and added 20% Dragon Race fuel (true 95oct R+M/2) to tank and its gone. Not sure if it needed higher octane or more air. Dealer said if its a bit rich it can reignite, also alcohol is in fiel now days and doesnt mix well with oil so could leave unburt fuel on sides of head to reignite, could be pre ignition too. Im using br7 plug, i think its hotter than br8, nit sure if it helps or hurts. Still learning i guess bro

The hotter plug and more air would have made the problem worse and more prone to detonation or pre-ignition, you likely fixed the problem with more octane/better fuel.