valve spring retainer broke on dyno, what was missed
#1
valve spring retainer broke on dyno, what was missed
09 Road King....so I have 1200 mles on my 106 kit with 583 easy start cams and we were doing the final tune yesterday. On last run front intake valve retainer broke causing valve to stick open which im sure took out piston (havent gotten that far yet). Pulling it apart today and just wondering what was missed in assembly. I have stock heads with stock beehive springs. Too much spring pressure with this cam?? Are stock springs ok for this cam (583 lift)m now going to pull both heads and recheck everything and possibly change all springs and retainers. Just curious what I should be looking for. from what I have read stock springs should be fine with this cam. Any words of wisdom from the motor savy people?
#2
#3
Ive read they are ok up to 600 lift. Im thinking you may be right! Got everything apart today. Have to replace front and rear pistons, front head is screwed as it has large gouges in the combustion chamber area. Rear combution chamber has a couple of small gouges (could be fixed I think) Front intake valve bent, seat broke. It seams a piece of the seat got into the rear head and thats what took out the rear piston. I need to find a set of used heads and go from there I think. I wil post a couple of pics. Pretty bumbed right now.
#4
You can go to HD's website and find the "Racing" section which gets you into the SE Racing Parts catalog. It's been a while since I last visited (a couple of years or so) and I seem to recall that the stock springs were fine for up to .550 lift (e.g. the popular SE-255 cams).
Regret to hear of your difficulties.
Carl
Regret to hear of your difficulties.
Carl
#6
Stock springs, too?? Did you measure your distance to coil bind on reassembly? If not, me thinks your engine's living on borrowed time. You may want to check into it a little more. I believe you need (depending on who you believe) 50 to 60 thousandths clearance to be on the safe side.
#7
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#8
Is it possible that the valve heated and expanded or that at high rpms (on the dyno) that the valve floated and hit the piston and that knocked out the valve keepers??? are you using a stock head gasket??? did you clay the clearance for the piston to valve??
Last edited by mrfikser; 05-05-2012 at 07:15 PM.
#10