BAM West of Tynda in July
 

I'm in a group of three leaving Japan mid June via Sakhalin to Vanino bound for Mongolia and beyond. Having read so much of Walters adventures I/we are keen to ride at least part of the BAM, the bit West of Tynda. In the Sibersky Extreme Project that part was tackled in August and we'll be a full month earlier than that. I've noted the weather and it seems we should be OK as far as rain is concerned. Any and all advice greatly appreciated.
Bikes
1 x DRZ400S
1 x BMW F650GS
1 x Will be one or the other of these bikes. I hope it's the DRZ. :-)