Topic: CL77 points shaft orientation

[the-chauffeur]

I have a horrible feeling about this, and if you know anything about these engines you may be able to guess what comes next . . .

 . . . I've just finished putting together the CL77, and after pulling it apart to re-orient the camshaft (yeah, back to front), I thought I was done and put the engine back into the frame.  But it's just occurred to me that there were no discernible marks on the points shaft (or camshaft for that matter) to tell me which way the shaft should fit.  Just to be clear, I'm referring to this bit:

Knowing that spark advancers on newer bikes can be oriented the wrong way, the painful realisation has dawned on me that I may have inadvertently put this thing back in 180deg out.  Once again, the manuals are absolutely hopeless on this bit.  Yay.  And yeah, if I've got it wrong, the engine's gonna have to come out again . . .

So, anyone know how to tell whether the shaft is oriented properly?  Fingers very, very crossed that it can be oriented either way (although the way things have gone so far, I highly doubt I'm that lucky).

Thanks all

[tbpmusic]

I can't answer this - but the folks at https://www.hondatwins.net can......

[Bodi]

I believe the CL77 uses the 180 degree crank and Type II ignition... if not and it's the Type I 360 degree crank, it's a similar process but you only have to check that the points open at TDC.
For Type II: Turn the crank forward until one points set just opens. Check which cylinder is at TDC or close - the rotor marking should tell that or look down the plug hole (I have found Type I rotors on Type II engines). Check the wire color on that points set and on the coil for the cylinder at TDC. If the colors match, yay! If not... ouch.
50/50 bets like this, I tend to lose. Big USB connectors go two ways, and always seem to be the wrong way on my first try.

[the-chauffeur]

Thanks gents.

I got a response on HondaTwins and it sounds like Bodi and I share the same luck . . . long story short, I was told the points shaft was 180deg out.  I'd managed to get the cam sprocket correctly aligned with the crank, but I got the shaft - literally.

Oh well; given that I know what the problem is, it's easy enough to fix.  So I've pulled the engine, fixed it, and put the whole lot back again.  I'm at about the same point in the build as I was last night, only this time the camshaft, the crank and the points cam are all in line with each other.

Thanks again.

[the-chauffeur]

Quick postscript to this . . .

 . . . turns out the way I had it set the first time was right, and the advice I was given . . . well . . . not so much.  After taking the engine out, rotating the shaft and putting the whole lot back in the bike, there was no way it was going to fire.  With all of the pointers facing up, the engine is on its compression stroke but the points are wide open.

So yes, the engine needs to come out again.  What joy.  To anyone who needs to know in future, time up the cam sprocket with the crank and then fit the points plate.  Turn the engine over by hand while looking down the right hand plug hole and make sure the points close on the compression stroke where the intake valve has just closed. 

It's really that straightforward.  If only I'd realised that last time . . .