ct 350 pv pinging

[lon350pv]

I have an 86 trx 250 with a ct 350 pv. Jetting Main 190, needle is a dgh on the 3rd clip, pilot is a 50. I run VP c14 114 oct, fuel. It pings alot. I have moved the clip down and it to rich(blubbers). I have gone up main and it blubbers. I feel the main is still to rich. I don't want to lean the main out any more until I fix the pinging. Does anyone else run VP or have had luck with another fuel.:confused:

[QuadRacer041]

what carb are you running?
how does the plug look when you do a test?
could be your ignition

[barkbuster350r]

I have an 88 with a CT 350 power valve 38 carb run 50% vp c-12, 185 main jet have never had mine to ping. Not sure what your ping is, but these bigger motors sound nothing like a standard 250r.

[TRX370R]

I have a ESR 370 with a 40.5mm carb 190 main. Have ran VP C12 and Trick 110 with no problems. How is your cooling system maybe it's getting hot?

[lon350pv]

I am running a keihin 39. My plug is a yellowish color. I run maxim oil which is a gold color and the c-14 is gold color.

[2FIFTYR]

no matter what color the gas is with or with out oil a properly tuned two stroke will be a coffe color in every rev range on your plug chops. sounds a bit lean with a yellowish plug. where at in the rev range is it pinging? bottom middle top?

[YFZRob]

It sounds like your needle is the problem. I too had detonation issues, even after swapping to race gas on the pump gas dome. After lots of trial and error, I found out it was the DGH needle. The needle is too long. I had to run mine on the 5th clip position and it still pinged a little. At ESR's suggestion, I went to a DDJ needle, which is leaner on the 1/8th to 1/4 throttle due to one size larger in diameter, BUT, it's 2 sizes richer on the length. It ran pig rich on the 4th and 5th clip, but as soon as I got it on the 3rd clip, WOW. It ran great and ZERO detonation. The DGH needle needs to be run on the 5th clip MINIMUM with that motor in my opinion. If my 310 kit detonated on race gas w/ that needle on the 3rd clip (sea level, 90 degrees), I would think your problem is the needle. Try the DDJ on the 3rd clip and go down from there if you have detonation still.

[lon350pv]

It pings mostly in the mid range. I have moved the clip to the 4th pos. and it missed and blubbered like its rich. Where did you pick up the DDJ needle. I have been fighting the jetting on this motor sence the day I got it. I had a 310 before the 350 and had no trouble.

[YFZRob]

Something is strange with your combo then.....maybe an air leak? The DGH needle ONLY worked for me without detonation on the bottom (5th) clip. I don't know why you seem to be rich with it on the 4th clip since my 310 on Sunoco Blue 110 with a 50 pilot, 185 main, and DGH needle detonated on the 4th clip or higher. Since your case is different for some reason, I don't know if a DDJ needle would help. But you can try it... go to www.sudco.com to order them. I think they are only $5.75 each from there and they stock EVERYTHING.

[lon350pv]

I want to thank you guys for all the input. I have a few things to try and hopefuly this will help.

One other detail is the that the recommendations CT made was to run a br8ev or br8eg spark plug. Does anyone else run this plug or do you just run and stock br8es.

[sandspanker]

:( Sry for the trouble. You might have a bad crank seal.with it running spray some carb/brake clean on the base gasket,intake,also take your.flywheel cover off of just loosen it up and see if the RPM changes. I have a 350 PV 60pilot,dgk needle in the middle with a 172 main all in a pwk 39mm carb. I hpoe you figure it out.:)

[TRX370R]

I have tried a few other plugs but always have had the best luck with the BR8ES gapped at .018

[lon350pv]

This motor has been trouble for the day I got it. It is very hard to start. I kick my guts out to start it.
I did not do the work myself I sent the motor to CT to have all the work done. When it came back it was ready to bolt in, break in and run. It basiclly is a new motor. New crank, rod, seals, bearing and 6 new gears. And the new 350pv kit, carb, reeds, bottom line only the case are original. :ermm:

[sandspanker]

:) try this when you start it. choke on,roll the engine over slow 10 to 15 times,Then give it a real hard kick,I have seen so many people kick their brains out kicking on a cold engine. I give that advice to them and the bick starts every time. let me know how it works.:p

[YFZRob]

That sounds odd about your starting problems. I cannot image why it'd be that hard to start. My 310 kit started just as easily as the motor did bone stock....one kick when cold, sometimes two when hot. I'd definitely test for air leaks before anything else.

[powerslider]

The 350's are a pain to start if your running high compression, the problem is spinning the engine fast enough to generate spark. I have to roll the piston just past tdc and then grab a full stroke on the kicker with all you got and it lights up.

Try kicking it a few times with the choke on and no throttle to prime the engine, then crack the throttle a bit and as I mentioned above position the piston just past tdc and give it a strong full stroke on the kicker....

[MR.BIG]

Why don't you call CT and see what they have to say since they did your motor?