I had the same noise at 21k, I could only hear it at low speeds or if the sound bounced off a retaining wall. It was kind of like a low speed grind, intermittently base on wheel speed. In my case though it was a frozen link on the chain, although it was not really apparent.
IMHO, If it where my front end I would be leanig to the wheel bearings at 35 k if they have not been replaced.

 

Did you fix the noise

My 2007 DL650 has now developed a whirring noise which appears to be coming from the front wheel area. I also tried to ride with my head as close as possible. No luck in identifying what it was. Took to a mechanic (not a specialist in Suzuki) he took it for a run and came back bewildered but didn't think it was major and perhaps coming from speedo cable. Anyone got any clues? Thx in advance R

 

The speedo sensor runs digital inputs into a wire. Avoid any mechanic that believes there is a moving cable in there. If the sensor gets dry, it will make noise. It needs to be removed, the two parts separated and have grease applied to the interface of the two parts.

 

Is wheel bearing grease okay, or something "special'?
Thx GW

 

I had to replace the front wheel bearings on my 09 at about 40k for just such a noise. Bearings were inexpensive online and easy to replace myself. Took about an hour and cost me about $12. I went ahead and ordered rear bearings at the same time and replaced all three of them. Actually, I ordered two complete sets of bearings, and the second five are kept under my set with the factory tools.

 

I have a noise in the front of my '07 Vee that sounds almost like tire howl, at speeds >50 mph. Wonder if it's the speed sensor? Or actual tire howl... (Michelin P3s)

 

My 05 had a front end whirr at around 70K km when moving off vertical so I popped the wheel bearing dust seals and repacked with some more grease and the noise disappeared.
Just finished a 5000 km Easter trip with 76000 km on the clock and no noise from the front.