Compression problem

Octo Ro

New Member
May 1, 2019
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At the middle front of my engine in between the head and the cylinder, I can feel air coming out whenever I pedal. It's also very easy to pedal even with the clutch out. I have tried changing the gasket and torquing the head bolts the **** down to try and close the gap. I also used a brand new head(stock). Some dude helping me said there was also a gap in the back. It was hard to put the head and gasket on and take them off too. Like, the studs are angled somewhat outwards and I have to like pull them in to move the head and gasket. The bike won't start at all and I'm positive this is the problem, or at least the main one. The new head also appears to be very slightly bent now, and the old head(also stock) is cracked in the middle on both sides. Wtf?
 

Greg58

Well-Known Member
May 1, 2011
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Newnan,Georgia U.S.A.
Take the head off and check it for flatness on sandpaper on a true flat surface, sand the head in a circular motion like waxing a car. If you have high and low spots you'll see them after a few circles, sand until the surface of the head is sanded uniform. You can start with 180 or 220 and finish with 400 grit.
 
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Venice Motor Bikes

Custom Builder / Dealer/Los Angeles
Mar 20, 2008
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Los Angeles, CA.
It is very easy to warp the head (& cause those gaps) by over torquing the head bolts!!!!!

Sand the head down (as Greg58 said above), then install a new head gasket & torque it down to 12 ft/lbs.