I am a beginner biker and new to this forum so sorry if I sound stupid. I have a 2002 GS500 with approx 10k miles on it. I have a bent exhaust valve and cracked exhaust valve guide on the left cylinder -> no compression. I have no idea how this happened, unless I already bought it with this problem and it got worse with time. I took the head off yesterday and I am going to send it to a machine shop along with a new valve, valve guide, springs, etc...
I read all the posts about cam timing when putting the thing back together and I understand the positioning of all the marks on the rotor and cams... But there is one thing I don't get. The plug on the right cylinder fires every two revolutions of the crankshaft, correct? Then, when I have the cams off and the right cylinder is on top (R.T. mark on the rotor aligned with the left pick up) how do I know that it's the right cylinder firing revolution? In other words, I am afraid that I will install the cams just like the markings say but the spark on the right plug (and consequently on the left) will be one crankshaft revolution out of phase. In this scenario, the right cylinder would be on top, the spark would fire but then the right intake valve would open instead of the exhaust one.
Can anyone help a newbie out? Thanks,
Gregory
Starkville, MS
The whole tining thing I dont actually know, but the GS has a wasted spark ... it fires for ever 360 of the crank, as in it fires into the exhaust gasses as they are exiting the thing.
Cool.
Srinath.
the timing marks only align one way on the crank, set the crank so that the right cyl is at top dead center (piston all the way up) stick a screw driver down through the spark plug hole to use as a gauge. when you find TDC you look at the timing marks, and turn the crank BACKWARDS to whare the marks line up. and then you are on the mark, so to speak.
Quote from: seshadri_srinathThe whole tining thing I dont actually know, but the GS has a wasted spark ... it fires for ever 360 of the crank, as in it fires into the exhaust gasses as they are exiting the thing.
Cool.
Srinath.
Thank you Srinath. That's exactly what I needed to know.
So, as long as the R.T. mark on the rotor aligns with the left pick up and both valves on the right cylinder are closed then I'm fine.
Cheers,
Gregory
Starkville, MS