Hi I am a new member. I have had my S-40 one week now. I noticed upon putting gas in for the first time several days ago their was no trip meter. What do you all do as far as keeping track of how many miles you go inbetween fillups?
I have been told you can use a combination type lock.  The ones with the 3 numerals that you twist each time you fill up.  
Thanks and love my new bike.. I rode a Rebel 250 for almost the last 2 years..

I just write the mileage when I fill up on the gas cap in dry erase marker.  Works fine.  I fill up at about 100 miles.  I seem to be riding 200 miles/week at least, so the stuff doesn't wear off in that time.

I have a big display bicycle computer on the way.  I'll get it all calibrated up, then I'll have a speedo, tripmeter, elapsed time, etc.  on the bar.  I really can't see the speedometer when I'm riding, anyway.

I too have a 3 digit luggage lock similar to the one pic's above ... mine is attached to the bars between the riser clamps with some 2-sided tape ... just dial up the last 3 digits on the speedometer each time I get fuel ... works great and only cost me a buck for the lock!

Yeah, that's what I do.  Glance at the filler cap.  If it says 11118 and the odometer reads 11201, then I stop the next time I see a station.  I've only hit reserve once - about 3 miles from the station I was heading to. My normal fillup is 1.7 gallons, so I'm not hitting it too close.

I'm getting some MSR quart bottles, too, so I can carry an extra gallon for going over the mountains.   Not that there aren't stations, but there aren't enough that I can handle having a key station closed!

I dont hit reserve very often, but I run on it every now & then( well, actually, I can pull the lever easier, so I use prime) but I run the fuel off the bottom of the tank. I know the vibration probably keeps any crap from settling, But I am just that way..