Primary drive gear GT550

[gdh12bike]

Putting together my GT550 after getting the crankshaft seals replaced. As I’m putting the right side engine cover back in place, I find that the shaft that acts as the distributer is not engaging into the primary drive gear. I believe that there is supposed to be a pin that protrudes from the gear that engages with the distributer shaft but instead of protruding, it is really flush with the face of the gear. I can't seem to find a break down with enough detail that shows what the gear is supposed to look like, and am wondering if anybody else knows what I might be doing wrong or not understanding.

Thanks for any input,

Gary

[H2RICK]

You're correct, Gary. That pin SHOULD protrude from the gear face to engage the slot in the inboard side of the "cup" that is part of the "distributor" shaft. There is also a disc doodad that sits inside the cup that spaces everything correctly and stops everything from rattling, as well.
Have you tried to extract that flush mounted pin from the gear ??
I can't remember if it's part of the gear or not.....but IIRC it IS separable.
It has been a lonnnnggggg time since I've had that side of the 550 engine apart so it's all rather fuzzy now but, IIRC, that pin is nothing more than a roller from a roller bearing. It, of course, will have metric dimensions. It MAY even be the same one as used on the Water Buffalo but I can't confirm that.

Unfortunately I don't have a paper parts manual for the 550......and, apparently, CMS in the Netherlands is the only place I've been able to find one online.......and it doesn't show what you need to know.
The only place you can kind of see how everything fits together is in the exploded view of the engine on mr axl's site.....but even HE doesn't have a parts book....and the factory service manual for the 550 is totally useless in this regard. As well, the exploded view doesn't show the face of the gear you need to see.....but it appears in the exploded view that the pin IS separable from the gear.

At the end of all my blathering, I'd get a magnet and try to extract that pin from the hole in the gear face. It just may be that it has been sheared off by a PO.
Let me know how you make out. If worse comes to worst, I believe
our buddy Fred may have a spare engine for comparison.

[gdh12bike]

Thanks Rick! I'm going in now, so wish me luck! - Gary

[Cliff]

Is it possible that the gear is installed backwards on the crankshaft? I have a gear in my hand and a crankshaft on the bench in front of me. The inside of the gear is flat except for a 1mm shoulder around the center. The outside of the gear looks like this: Gear teeth around the OD, then an eight mm wide groove with the pin in it and the rubber dampener, then the center hub. The pin is installed flush to the gear face on both sides.
The "cup" on the back of the camshaft (YES this 2 stroke has a camshaft!!) fits into the groove in the gear, and the notch in the cup aligns with the pin.
If the gear is installed with the groove to the outside, that's correct. When installing the clutch cover you will have to turn the camshaft to line up the pin and notch. If everything lines up and is installed right, the cover should go on tight to the crankcase. DO NOT try to pull it on using the bolts!! If the cover doesn't push on by hand then something is not lined up!
Hope this helps! Let us know how you make out!
Cliff.

[gdh12bike]

Well, as it turned out, the gear was installed backwards by some dummy (I can't think of who might have done it!). Anyways, everything went back nicely once I had the gear on the right way.
Thanks so much for the input guys!

Gary

[H2RICK]

Way to go, Gary !!! I'm glad it turned out okay for you.
Some "combined brainpower" can go a long way, sometimes.

[Cliff]

Glad we could help! Keep us posted on your progress!
Cliff!