Just Burned The Head Gasket

IMO,you need to vary the load and never maintain a set rpm;loading and unloading the engine basically heats it up briefly and then lets it cool. I wouldn't keep 4k rpm as a max,you can safely run higher rpm then that. I'll let the builders who are more knowledgeable then I am give their suggestions. You can also break the engine in on a dyno;which I have done successfully in the past as well. Lotta different theories on the proper way to break an engine in.
You are right but for the first 200 miles i will never exceed 4K rpm just to be safe.
I also agree on varying the load.
Chris
 
unfortunately it really doesn't work like that. if the motor fails and the pistons get burned he is not gonna replace them for free. I wud ask for that in writing cause otherwise he will just say somethn else went wrong and the pistons are collateral damage now.

I don't personally know anyone that uses Wiseco other then friends that race dirt bikes. don't see them in Turbo motors very often. seen plenty of JE, CP and Wossner tho. any piston can fail tho so as long as he stands behind his work then I wudnt be too concerned about it. if its not built yet tell him u want Wossner. its ur fukn bike and money not his!

I would like the Wossners which also have the skirts coated but my builder insisted so it is his responsibility.
Chris
 
Hitting the limiter is likely what caused your issue, almost always a limiter problem if it is #3 with an issue

Richard
 
Hi.
Your opinion matters too much for me so can you please elaborate why the limiter can damage the engine?
I know that fuel soft cut would damage the motor but i have selected hard cut.
Can anything be done (a device or a strategy) in order to avoid this in the future?
Btw the head gasket was burned at piston #3 near the intake valve region where the pistons look almost clean and silvery.
I just remembered that the day that this happened i did hit the limiter with the 3rd or 4th gear in.
Chris
 
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Here is the moment when i hit the limiter having the third (or fourth i don't remember) gear in.
The exact moment is to the left of the cursor line where the rpm remain constant (3h10:39.3)
The pulses on the rpm data are gear changes with clutch pull.
I have also addressed the af ratio being lean at low gears by using per gear fuel maps now.
When at 6th gear the af line is completely flat with no peaks at 11.5 : 1, it was only at low gears that the af was leaner.
Chris

limiter_3rd_gear.jpg
 
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Today i went for a long and peaceful ride (break in the motor) and i noticed that the engine has a lot more torque from 2K to 3500 rpm (that was the max rpm)
and it revs much faster from idle to 3000 rpm than she did when i bought her (with 11.5 :1 compression and not 9.5 :1 that she has now).
This probably means that the pistons work fine SO FAR.
Chris
 
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