mmmmhh....I've got a DR350...and in talking to others, hot starting can be a problem with the big single!
As for a starting technique, it is just that. This topic has been discussed many times on various DR forums/sites and the general concensus...is that there isn't one. It does seem to vary from bike to bike.
Try this website
http://www.maximum-suzuki.com/ibf/ Scroll down to the DR section and do a search in the general and techie sections. Also register and ask the question....the guys on this site are mainly based in the states but eat, sleep and drink DR's...what they don't know .....and are very helpful.
Hope this helps