本帖最後由 BHP 於 2009-4-26 11:02 編輯  
180 degree!!!!   Good luck with your engine as normal operation temp for .21 and .28 should be around 110 and .12 a little hotter, around 120.  For break in keep it around 70 to 90 degree.  If your en ... 
jf813 發表於 2009-4-26 03:34   
 
Crankshaft usually breaks during the first 2 tanks during break-in, 
when the newbies are running too rich thinking it's better for the engine, 
which only adds more non-compressable fuel into the engine --> compression too high --> breaking the crankshaft. 
 
Break-in method and temperature are delicate matters, 
and there are many debates on this issue. 
Some people like to keep it under 100*C during break in, 
but after break-in, they play at 130*C. 
What happens is that it expands larger at 130*C, causing air leaks and poor performance. 
 
I go the other way. 
I heat cycle my engine up to 130*C, my normal playing temperature; 
keeping the revs in all ranges but not full-throttling to reduce stress on the crankshaft. 
In other words, I break-in at the temperature I play at.  Makes good sense?  ; ) 
 
Sorry I'm not the old school type, 
which idles a new engine with 3 turns open, 
spitting fuel out thinking it's better for the engine.  I don't believe in this {banned}    
It's like a tennis player practicing in an air-conditioned room at 20*C for 2 months, 
then go out to play in tournaments at 30+*C. 
He'll just die.  Same with engines. 
 
***************** Summary ****************** 
The idea is to have your engine "adapt" to the conditions which you'll play at. 
In my dictionary, break-in simply means "adaptation". 
Afterall, that's the ultimate goal isn't it? 
To have your engine run smoothly and healthily at the conditions which you'll play at?      
 
Cheers  ; ) 
BigHead |