Calitoz,
I've never been into one of these so correct me if I'm wrong, but you talk about needing to have the piston at absolute TDC in order to avoid having the cam chain jump, presumably from being moved by a valve spring trying to close an open valve, when the CCT is removed. It seems to me that this would only be true if the piston were at TDC of the exhuast stroke, and that if you rotated the crank 360 degrees and the piston were at the top of its compression stroke, then both valves would be closed and all four valve followers would be on the heels of their respective lobes and you would have quite a few degrees of crank play before a lobe would start pressing on a valve and everything would stay put.

Also, you talk fighting engine compression by moving the engine via the rear wheel in high gear. Why not simply remove the sparkplugs in the first place and rotate the engine with a wrench? Plug removal would also avoid any possibility that engine compression would cause any parts to move when tension was removed from a cam chain.

Looks like a pretty easy job as far as engine work goes, in fact the biggest thing I'm worried about is maybe having to take the fairing off, what am I missing here?

 

I believe you are correct in the assumption. Correct me if I am wrong, the thing about this method is without removing the cam cover, you can't tell what stroke it is at. . At absolute TDC as indicated by the crank shaft "RT" and "FT", it is safe to remove the CCT without it jumping. Obviously the best method is to remove the cam cover and rotate it until no cam lobe is putting any pressure on the valve stem. At that point, it is irrelevant if you are TDC or not.

I did not try your method but it sounds logical. The issue is whether you want to go through the removal process of the sparkplug. I find it a pain.

It is easy enough if you are patient....as for the fairing, it is the easiest removal process of any bike that I've encountered.

 

No..do it now...if anything, for the peace of mind

 

[quote=calitoz;140616]I believe you are correct in the assumption. The thing about this method is without removing the cam cover, you can't tell what stroke it is at. Correct me if I am wrong. At absolute TDC as indicated by the crank shaft "RT" and "FT", it is safe to remove the CCT without it jumping. Obviously the best method is to remove the cam cover and rotate it until no cam lobe is putting any pressure on the valve stem. At that point, it is irrelevant if you are TDC or not.

No, the cams are geared to rotate once for every two revolutions of the crank, so without removing the cover you have a random 50/50 chance of being on the compression stroke when the "FT" or "RT" appears. If you happen to be at TDC on the exhaust stroke and a valve is open when you remove the CCT you risk the valve trying to close and a jumped tooth. Gotta check those valve clearances anyway so why not just remove the covers so you can see what you're doing?

One additional thing that occured to me is to only rotate the engine forward in order to insure that all of the slack is on the back side of the chain where the tensioner is located before removing it. That way you can be reasonably sure your initial setting of the manual CCT is accurate. I would then rotate the engine for a few revolutions and recheck the setting, again on TDC of the compression stroke. When it comes to engine work, mistakes can be very expensive.

 

You're correct about the revolution ratio of camlobes vs crank however, when at TDC it doesn't effect the removal of the CCT irrelevant of exhaust or intake stroke. There are two distinct camlobe position at the each RT or FT mark as mentioned above. One where absolutely no pressure on the valve stem [cam are pointing up] and one when they both make contact with the valve seat but not enough pressure to jump the chains when tensions are removed.

Lastly, at absolute TDC on the exhaust stroke, the valves are NOT open contrary to your above statement.

Bottom line is this at absolute TDC it is safe to remove the CCT

I don't disagree with you on whether or not to remove the cover as it is a better idea especially (adjustment of valves are in order, you going to change the oil anyway, etc) but I will leave the reasoning for not removing it to others and there are a number of reason why it is preferred.

As for your statement of rotating the engine in forward motion, it is redundant and is assumed as forward motion (natural tendency) is much easier then trying to reverse it to get back to the mark.

Remember, this how to is a generalization of how to do the CCT. There are other ways to do it and I will never say one way is better then the next. This is just my way and the quickest way not necessarily the proper way according to others. When is the last time two mechanics agreed on the methodology of the removal of a 9/16 bolt?