If it goes away when the tyre warms up, I would say the tyre is the problem.
The rear tire has about 25% wear also, but does have a little "cupping" and has always "whined" in the curves since I've owned the machine. (Sept. 2011.) It had 68,000 when I bought it and the tires really don't look or measure much different now. (now 74,000)What is the conditions of the back tire?
You got a good point there...LOL...It does make sense though. I'm waiting for it to warm up a little this morning; "39 degrees" to put it on the center stand and inspect things closer.It's only in the AM or "first half" of the daily round trip, not at the start of the return "second half" huh? Perhaps it's just the bike sensing your sleepiness still and waking you up the best way it knows? Or maybe it's because that's when the tire is it's coolest and at it's lowest inflation?
I last rode to work this past Thursday at 7 AM, 59 degrees...nice; Friday drove the wife's car because of rain...wanted to ride this morning, but changed my mind because I didn't want to shiver. :grin:39 degrees, are you sure your not shivering?