tank swap?

I have a 78 kz650sr and I'm not a big fan of the style of the tank, plus it has no cap either. I was wondering if any of you experts here can tell me if I can swap a regular 650 tank on to it without to much hassle. I guess what I'm getting at is will it drop right in or not? Thanks for the help.

The answer to your question is yes and no. The stock 650 tank will mount up just fine both front and rear, but the SR tank is shorter so if you put the Std 650 tank on your SR you will run into issues with the front of your seat being in the way. I hope this makes sense, the SR has a longer seat than the 650 B or C to fill the gap of the shorter tank.

Sounds good so far. It's not a big concern about the seat cause I'm going to be doing a custom seatpan and rear cowl anyway. Is there any difference in the petcock or the mounting rubber? Thanks for the info.

No, the petcock and mounting rubber is the same. If you do the swap you will lose the low fuel warning light though. The 650 B&C tanks don't have a hole in the right side to accept the sensor.

i just put an old round tank on my SR instead of the coffin tank - i need more fuel - and i think the old round one looks better. it's true that the tank rubs more on the seat - but i'm putting a kz seat on mine and redoing the back of the bike so it looks like a std KZ and not the saggy bottomed SR

only thing i miss is the fuel warning thingie - but i guess i'll drill a hole for it .

In respect to the low fuel warning light, isn't that what the reserve is for? The way I see it the less wiring the better. I'd like to remove as much wiring as possible and go bare bones, kickstart and just enough to make it street legal. Does anyone know where to get a plate to cover the hole for the starter by the way?