Just had a 95 in re build with SE 10.5 pistons, 204 cams, tts tuner and fat cats done. Have about 200 miles on the new engine and having some pinging when I accelerate from 4th or 5th gear under load . its pretty slight and only happens when I crack the throttle. My mechanic says to run the bike for about 500 miles then he will dyno tune it. Question, is the pinging normal? I'm using 93 octane Shell gas.

Thanks

 

Do what the Mechanic is telling you to do and then pose your question after the Dyno tune if it's still pinging.

 

With the intake closing number of that 204 cam, we sign off at 10.0 cr, as that is hovering at/near 200 psi ccp.
That is our threshold here.
Scott

 

I agree with scott,if your mechanic was the builder,he should have known this.go with a set of S&S 585,andrews 50,SE 257 or woods 7H cams (among others),but any of these will work well with the 10.5-1 with no detionation (and I would either stay out of the throttle or change the cams now,detionation aint good for a motor,especially HD lower ends)

 

And it'll eventually blast the top off the piston between the intake valve relief, and top ring land.
Scott

 

Listen to Scott and Kirby. Been down that road with the SE204 with CCP near 200psi. No issues during the cooler months in south Texas but when July and August came around and ambient temps were hitting high 90s and 100*+, the ping started. Couldn't take enough timing out to eliminate the ping and still have a strong running motor. A cam change is in your future and I would not try to tune the motor in the current configuration. Change cams and then tune.

 

Took a trip to the mechanic who hooked up the TTS tuner. A quick adjustment and I was off and running. No more pinging and the bike runs great. Temps here in NY have been well into the 80's which is when the pinging started. WE'll see what happens in the next few hundred miles.

 

keep an eye on your plugs.little black specs on the porcelien is signs of detionation (acctully little pieces of your pistons)

 

If it does not ping, it is not 10.5 cr.
Scott

 

Here is the part # for the pistons
HARLEY-DAVIDSONŽ SCREAMIN’ EAGLEŽ PRO TWIN CAM HIGHCOMPRESSION CAST PISTON KITS* – 3-7/8" - 22661-99A


These high-compression 10.25:1 cast pistons are designed for use in a Twin Cam engine equipped with stock cylinder heads and 3-7/8" cylinders (1550). Piston kit includes rings, clips and pins. All EFI models require ECM calibration (priced separately).

Cams are se 204 part # 25149-00