Joined Jan 2014
65 Posts | 25+
Vancouver Island, BC
Hi, I own 2010 FE390 (70degree) and am in the middle of checking the valve clearances.
I used a narrow cylindrical watercolour wooden paintbrush with the handle down to check TDC via the spark-plug hole while lining up the two marks on the cam chain sprocket. I've done this for years, reasoning that it would not harm as the wood is relatively soft. As I slowly spun the back wheel in 6th, the paintbrush receded slightly as usual as the piston got to the bottom of the stroke. As it started to come up, I went to mark the brush with a BDC line, but as I moved it, the last cm or so must have bound on something. I gave it a gentle tug, and the brush split, leaving, I'm guessing, about 1-2cm (3mm diameter) in the cylinder. Unfortunately, despite despite using a vacuum connected to perfectly sized clear vinyl hose, there is no sign of the small piece of wood. I have sifted through the empty vacuum container and it definitely isn't there. I removed the header to see if had miraculously been deposited in there, but no joy...
First, what the heck did it bind on??? Surely the bore is too tight. Are there any other orifices in there, apart from the valves that I am not aware of? And are the valves, as I expected directly above the piston? (therefore it couldn't be them...)
Second, any ideas on how to get it out without removing the cylinder head?
Third, would buttoning up the bike and running it be a bad idea...I think I know the answer here.
Thanks for your help.
I used a narrow cylindrical watercolour wooden paintbrush with the handle down to check TDC via the spark-plug hole while lining up the two marks on the cam chain sprocket. I've done this for years, reasoning that it would not harm as the wood is relatively soft. As I slowly spun the back wheel in 6th, the paintbrush receded slightly as usual as the piston got to the bottom of the stroke. As it started to come up, I went to mark the brush with a BDC line, but as I moved it, the last cm or so must have bound on something. I gave it a gentle tug, and the brush split, leaving, I'm guessing, about 1-2cm (3mm diameter) in the cylinder. Unfortunately, despite despite using a vacuum connected to perfectly sized clear vinyl hose, there is no sign of the small piece of wood. I have sifted through the empty vacuum container and it definitely isn't there. I removed the header to see if had miraculously been deposited in there, but no joy...
First, what the heck did it bind on??? Surely the bore is too tight. Are there any other orifices in there, apart from the valves that I am not aware of? And are the valves, as I expected directly above the piston? (therefore it couldn't be them...)
Second, any ideas on how to get it out without removing the cylinder head?
Third, would buttoning up the bike and running it be a bad idea...I think I know the answer here.
Thanks for your help.
