Hello everyone, new member here, first post!
I tore into my 2005 brute today for a top end rebuild. I bought it with around 2k miles (I don't remember exactly) and now it has around 2600.
To start with symptoms: It has always ran OK but felt like it didn't have all the power that a brute force 750 should. Always smoked a little, exhaust smelled kinda funky, and goes through oil. So, I figured a top end rebuild was due (pistons, rings, gaskets, valve seals, whatever else).
I checked compression and both cylinders were at 56 psi (spot on) but I thought that was a false positive due to carbon deposit buildup helping the compression. So, I turn the motor to TDC rear (the TR on the crank rotor was lined up in the timing inspection hole) and pull off the rocker cover. Come to find out, the rear camshaft appeared to be 180 out. The timing marks on the camshaft were lined up with the head surface, but the arrow was pointing down instead of up. The front camshaft was lined up properly with the arrow pointing up. I took out the cams and pulled the heads. The pistons and cylinders look great - no scoring or scratching AT ALL. This is my first rebuild but in my opinion I would say they look damn near new.
Is it possible that the previous owner did a top end rebuild and the rear camshaft was installed 180 out?
Or is it possible that the arrow was put on the wrong side?
I am confused because I would think the motor would hardly run well at all (and possibly bend the valves?) but I've had it up over 50mph.
For reference, when the piston was TDC, the cam lobes were pointing up which I think would be wrong? That explains why there was no clearance between rockers and valves when I checked valve lash. I just thought it had never been done before. I want to make sure I have it right when I put it all back together.
Sorry to rant, just trying to give as much info as possible. Let me know what you guys think!! Thanks!
I tore into my 2005 brute today for a top end rebuild. I bought it with around 2k miles (I don't remember exactly) and now it has around 2600.
To start with symptoms: It has always ran OK but felt like it didn't have all the power that a brute force 750 should. Always smoked a little, exhaust smelled kinda funky, and goes through oil. So, I figured a top end rebuild was due (pistons, rings, gaskets, valve seals, whatever else).
I checked compression and both cylinders were at 56 psi (spot on) but I thought that was a false positive due to carbon deposit buildup helping the compression. So, I turn the motor to TDC rear (the TR on the crank rotor was lined up in the timing inspection hole) and pull off the rocker cover. Come to find out, the rear camshaft appeared to be 180 out. The timing marks on the camshaft were lined up with the head surface, but the arrow was pointing down instead of up. The front camshaft was lined up properly with the arrow pointing up. I took out the cams and pulled the heads. The pistons and cylinders look great - no scoring or scratching AT ALL. This is my first rebuild but in my opinion I would say they look damn near new.
Is it possible that the previous owner did a top end rebuild and the rear camshaft was installed 180 out?
Or is it possible that the arrow was put on the wrong side?
I am confused because I would think the motor would hardly run well at all (and possibly bend the valves?) but I've had it up over 50mph.
For reference, when the piston was TDC, the cam lobes were pointing up which I think would be wrong? That explains why there was no clearance between rockers and valves when I checked valve lash. I just thought it had never been done before. I want to make sure I have it right when I put it all back together.
Sorry to rant, just trying to give as much info as possible. Let me know what you guys think!! Thanks!
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