Is my transmission f#*@ed?

All right gents, you've never failed me before so here's the biggest one to date. "82 xj750. She been acting off lately. That kind of not quite right that you can't seem to put your finger on; indescribably little sqeaks that you might just be imagining, a hollow sound to the engine that might also be your imagination, not the same get up and go that she used to have. So I decide it's time to change the engine oil, and since it's warmer it's also time to go from 10w30 (which I've been using) to 20w40 as the Haynes manual recomends. Of course, my local autozone doesn't carry it so I get 20w50 for four stroke motorcycles. I'm pretty sure that can't be my problem.

After the oil and filter change I head out and make it 5 miles before I begin losing power. I pull over, she dies and then I can barely get her started.the starter mortor engages for a rotation or two until there's a grinding sound that seems to be coming from the gear box. I even pulled the oil fill cap and watched what's going on. The wheel assembly spins until the grinding and the wheel stops.

This is my daily rider. I don't have a car. I don't know anyone with a truck. So i roll started it ... and barely made it home. She's got little power and virtually none on hills. I was only able to make it by slightly pulling on the clutch lever when she started to bog down.

COuld this be the oil or is it a preexisting condition that presented itself by coincidence after the change. Am I going to have to pull the engine and get really dirty? I've fixed nearly every system on this thing already, but I have to admit the engine and gearbox has me a little spooked, that's the real thing mechanically speaking.

I appreciate any help you guys have for me.

 

The grinding sound could very well be the starter clutch slipping. The loss of power could be the clutch slipping but hard to tell from your description.

You said 20W50 motorcycle oil. What kind? I run 20W50 year round so that's not it. Did the oil have any friction modifiers?

 

Is it possible you WAAY overfilled the crankcase and the motor is "drowning" in oil?

 

I used Valvoline 20x50 with superior wet clutch protection. Nothing is said on the jug about friction modifiers. I know I didn't initially overfill it because I have to redo the calculations from litres (thank you Haynes manual) to quarts each time I do an oil change. I know it's overfilled now because I had my buddy bring me more in the fear that I'd underfilled it. You know ... the panic and confusion of a roadside repair can make people do stupid things.

What other info can I give you that might make troubleshooting this thing easier?

 

BY the way, Bigfitz52, you shouldn't have sold the Triumph. Those things are awesome. One of these days ....