quote:
Originally posted by 75SevenFityFo
Geeto, Yes, no rear fender. I hate the look of the tail like bracket. I was planning or making a custom one to hold the plate/light. Easiest way I figured. I am looking to have a tail of some sort and still have room for two. the 75'-78' supersport seat sounds like the most logical. I definatly like to function of the hinged seat. If not drilling, i could cut and weld the old hinges onto the new pan? Now to find a supersport seat

... thanks very much for the all the info.
the frame hinge unbolts for the SOHC supersport seat so just use that, if you absolutley need to weld then weld it insetad of bolt it to the frame. If you try to weld an assembled seat you will catch it on fire (ask me how I know). Supersport seats open opposite of 69-76 K seats so you really can't reuse the hinges anyway (although they both fit the frame - the shape of the pans are different. Also I don't know what you are going to do about a lock (not that you need it, several of my bikes have not had seat locks for years), the lock bosses are welded to the frame.
The cb750F tanks are longer than the cb750k tanks so the seat may still come up short if you bolt her in the stock position. May guys have their seats reupolstered to make up the difference (it is like 2 inches) or you could mount the seat forward and see if it fits.
if you look at this auction - this 1978 seat has the hinge still attached (second picture - the one of the seat upside down - at the top of the pic). You see those two bolt holes? that is what you bolt to the frame and the bike has a hinged seat again.
the nice part about the F seats tail is that it has a molded lip on the back of it that you can use to make a mount for your taillight and plate with some basic sheet aluminum and not have to worry about tire interference.
Personally I feel that cafe bikes are solo bikes, and that if you really want to ride two up you should ditch the idea of a fiberglass tail, or make a removable one like the biposto ducati sport 1000 or triumph thruxton have. also the weight of two riders can be a lot of stress on a seat pan so if you keep the stock seat and just clean up the fender area it would make a difference.
one idea you should consider is the old sparto "limp dick" taillights:
http://cgi.ebay.com/ebaymotors/CUST...VQQcmdZViewItemQQ_trksidZp1638Q2em118Q2el1247
takes care of your light mount and plate bracket all in one. Looks hella vintage and has a small footprint. You can mount it high up on the rear fender and cut off the rest.
here are 2 pics of cb750s. the frist has a chopped rear fender and a generic british lucas style taillight and plate mount. the second has a stock rear fender and sparto. If you remove the grap rail on the second you can move the sparto up and cut the rear fender like the first pic bike has.
http://gallery.sohc4.net/main.php?g2_itemId=20
http://gallery.sohc4.net/main.php?g2_itemId=2718