I am curious and concerned to hear so many of you voice concerns about weight.   A 12 lb bass is heavy?  A 14 lb bass is heavy?  I used to haul a 50 lb rucksack (back pack for all you hippies) for miles when I was in the US Army.  I have no back problems.  A wide leather strap with a sheep-skin pad works fine and I can play bass all night.
 
If you have issues with the weight of your bass: Do you exercise regularly? Do you lift weights?  Do you routinely do sit-ups to strengthen your torso core?

I have a series I and a SCD...Honestly, the weight on either does not bother me (except for when they are in the case and I am carrying them).  I use a Ken Smith strap, which has some fleece padding, so that probably helps.

I use a normal 2 nylon strap with my JPJ Custom - which weighs around 12 pounts I believe.  I do 3+ sets a night with no problems.  Of course I also exercise regularly and lift weights so that probably helps.
 
I tried using a Comfort Strap but it's too bouncy for me.  In my cover band especially I'm running all over the stage and jumping off stuff all night long - we tend to play on really large stages.

What about all those Les paul owners,i've yet to play a light one? Must be all the mahogany we strap 'round our necks...wouldn't have it any other way!
I own the P.A in my function band so unloading that at the end of the night is enough weight training for me every week.
I love my comfort straps, they work for me....

Brian wrote, I tried using a Comfort Strap but it's too bouncy for me ... I'm .. jumping off stuff all night long.
 
According to Wiki, Newton's three laws of motion are:
 
1 - A physical body will remain at rest, or continue to move at a constant velocity, unless an external net force acts upon it.
 
2 - The net force on a body is equal to its mass multiplied by its acceleration.
 
3 - For every action there is an equal and opposite reaction.
 
Now I'm not a physicist, but I've been trying to imagine how your bouncy strap is causing you to jump while you are playing your bass, and I'm just not seeing it.  I'm thinking there may be other causes for the jumping phenomena; for instance, the drummer may be applying to much velocity to the kick drum pedal, or the waiter is giving you caffeinated coffee when you order decaf.
 
(Message edited by davehouck on January 17, 2008)

LOL ;-)

Well, cant say heavy for the one Alembic I've owned (Essence), but if you want heavy, the old Peavey T-40 basses... mine weighed 15 1/2 pounds of solid Ash and honking big metal pickups and bridge.  I had to take up shoulder strengthing excerises to keep playing that bass.
 
20 years later, I still have memory pains.  
 
--T

scarlet is 12+ lbs
i use a moody 4 inch strap
so far no problem

My fretless Orion is a little above 10 Lbs, Brown Bass around 9 1/2 Lbs and 5 string Orion slightly over 8 Lbs. I use 2 1/2 inch straps and have no problems with my back.  
 
Keith

I've found that the weight of my SC Deluxe is the same or slightly more than the weight of my 7-string Bee bass, although about half the size.  Dense little sucker, that's for sure.

LOL @ Dave's post. :-)

I played a Carvin Bass in junior high and high school, solid maple (Eastern hard rock maple for the set-in neck and and body)
 
I never had a problem with its weight.  As an adult, the only thing I have an issue with is a set of 8-speaker bass cabinets.  Those are heavy.
What can be heavier than that?

Me.

My 6 is definitely too heavy to attempt to hold for any extended period.  Good to go with a 4 Moody's strap.  Feels just right!
 
(my Epic always felt too light)

My custom Alembics are heavy by design - they kill me, but sound great.  It's all about tone.  I practice on my Fenders and play on my Alembics.