My chain rests on a plastic guard that is mounted on the swingarm. When it's on my rearstand and I rotate the wheel, the chain rubs on this guard. I haven't adjusted the chain since it was replaced, so I assumed it needed to be tightened. Now that I've loosened the necessary nut, it appears my assumption was premature.

I've got 100lbs of weights on the seat (that's more than half my weight), and I'm showing about 1.25" inches of travel, on the lower portion. I'm eyeballing where the front edge of the tire visually intersects the chain to determine the midpoint.

That's on the tight end of spec (1.2"-1.6"), and as I understand it, it will tighten more when I sit on it. So it appears this chain is already at the correct tension. However, I don't clean and lube as often as I should, and the chain has to have at least 10K on it (can't say for sure, no odo on this bike), so I'd expect it to need adjustment by now.

I'm more likely to trust my measurement of the slack than I am to worry about it dragging on this plastic piece, but the manual doesn't seem to mention it that I can find. It's probably OK, but I tend to worry a lot about stuff that could have a detrimental affect to stability at speed.

What would you do?

 

Contact between the upper run of the chain and the chain slider is normal.
Slack is always measured using the lower run of the chain. Generally speaking, if the amount of slack in the lower run is correct, rest easy.
The Factory Service Manual shows indicator marks on the chain slider which help determine if wear is excessive. If it's any comfort, I yet to read of a chain slider on a VTR wearing out.
Assuming that chain slack in the lower run is correct and your setup doesn't include a ridiculous amount of ride height at the rear and the sprockets are no smaller than 15T fr and 40T rr, I wouldn't worry about contact between the chain slider and the upper run of the chain.

 

Awesome, thank you.

 

Also be aware that if you as I do have a spacer in the back shock that alters the chain adjustment.(6mm spacer on rear shock, a common mod on these bikes)

Recently I adjusted my chain and had what I believed was a bearing noise. It caused me all sorts of aggravation!

In the end it turned out my chain was too tight.

My chain almost touches the exhaust pipe when properly adjusted with the bike on a rear stand.

 

+1 Kenmoore