'08 V Star 650 Custom - Fork issue

I own a 2008 V Star custom 650. My husband and I just returned from Deal's Gap where we rode a lot of the nice roads there to include the Dragon. A TON of technical riding! (He is on an '08 FZ6)

Along the way, my front wheel started to "bounce" at lower to mid speeds like 20 mph to 45 mph. After we checked over the bike, we couldn't hear any noises inside the forks that might indicate broken springs but the front was VERY spongy with a lot of "easier than normal" travel in the forks. At no time has there been any oil leakage and the tubes are clean, clear of any scratches and look normal. No oil ever found where ever we parked, not even over night.

We stopped at Wheeler's in Robbinsville and when he had a moment, he gave it an initial look. He seems to think the same as my husband, that Yamaha put in less-than quality fork oil and the oil has broken down.

My questions are these: Has anyone put in after market springs? What weight oil did you replace the stock with? Has anyone else had this problem with the stock forks?

The bike is less than a year old and is under warranty. We're taking it in but Hubby seems to think they will give us the run around and call it a maintenance issue and charge us to change the oil. BTW, this bike has less than 4500 miles on it.

Thanks for any advice you can give.

Ride safe!

-=*{NH-VStar}*=-