Topic: cb450 gas tank on a cb550

[dminner]

Hey guys, real quick question.  Does anyone know if a 73' cb450 gas tank will fit on a 73' CB550?

[bill440cars]

         Hey there,

                 I'm not sure about the fit. I'll check it out and get back to you later today, if someone else doesn't beat me to it.

                                                        Later on, Bill

[dminner]

Please, I really want one on ebay an the auction ends in 2HRS!  I kinda waited till the last minute.

[bill440cars]

        Be back with you in just a bit.

                                                 Later on, Bill

[bill440cars]

         Okay, it looks like the only problem would be the front mount. If you shortened the pins (that the rubber mount slide onto) just a little and trimmed the 2 rubber mounts just a bit, it would lat the tank go in place and settle down okay. Now I don't have a rear mount handy, so I'm gonna have to guess on that part. I figure that if the tank can be put in place, it will work. Or you could modify the tank front mounts, but I don't think you'd want to do that. Personally, I don't see a problem. If you go for it and decide not to use it after all, you might could sell it over on cb450dohc.com.  Just a thought.
LOL on what you decide to do. 
                                                       Later on, Bill

[dminner]

Awesome, thanks so much for the help.

[bill440cars]

   


          Hey Dan, I screwed up! Yeah, the gas tank can be made to fit without much trouble. The kicker  will come when you try to put the fuel shutoff valve on. I only checked to see if the tank would be able to be mounted and then it dawned on me to check the valve and, unless you want to go to the trouble and expense of relocating the fuel shutoff valve, I wouldn't do it myself. I hope I'm not too late with this.   Let me know, okay?   If you get it and can't use it, I'll help you get rid of it.

                                                       Later on, Bill   

[puppytrax]

The kicker  will come when you try to put the fuel shutoff valve on.

Bill - I'm thinking of doing this myself; putting a Black Bomber tank on the 550. What's the deal with the fuel tap?? Hits the carbs??   

[bill440cars]

The kicker  will come when you try to put the fuel shutoff valve on.

Bill - I'm thinking of doing this myself; putting a Black Bomber tank on the 550. What's the deal with the fuel tap?? Hits the carbs??   

          Yeah,  on the later model 450s, the fuel valve connection on the tank, sits right on the far right carb. I don't know if the Black Bomber tank is the same or not. I can only guess on that one. On the one that Dan was inquiring about, it would take a little bit of work modifying the front mount rubbers and pegs, to gat the tank on the bike but then, you'd have to relocate the threaded pipe that the fuel selector valve goes on and, for me and some others, that would be just a bit much. That Black Bomber tank does have a good look to it and, if I had one, I've got a 450 project in the shadows that would carry it well.           Later on, Bill

[puppytrax]

On the one that Dan was inquiring about, it would take a little bit of work modifying the front mount rubbers and pegs, to gat the tank on the bike...

Right. They'd need trimming, since they are too long for the 450 tank. And the Bomber tank mounts with a bolt/washer/rubber grommet at the rear, instead of just slipping into a rubber block...

That Black Bomber tank does have a good look to it and, if I had one, I've got a 450 project in the shadows that would carry it well.

I will keep you in mind if mine looks like too much work...     I have a NOS 550 tank with one dent that I may try to pull out...nice & clean inside, a delight to look at...and the desirable spigot fuel tap...   

[bill440cars]

That Black Bomber tank does have a good look to it and, if I had one, I've got a 450 project in the shadows that would carry it well.

I will keep you in mind if mine looks like too much work...     I have a NOS 550 tank with one dent that I may try to pull out...nice & clean inside, a delight to look at...and the desirable spigot fuel tap...   

          Hey, I do appreciate it. I do hope it works for you but, if it doesn't work for you I really do appreciate the fact that you're going to keep me in mind. LOL on that one.

                                                    Later on, Bill  

[puppytrax]

I was able to do a bit of measuring last night (the Black Bomber tank won't slide on a 550 without trimming the front mounting studs down)...It looks like the 450 Black Bomber tank is ~1 1/2" longer than the 550 tank...the 550 frame has a hole which would accept the 450 BB rear bolt & grommet mount, but it's too far forward...the front mount width on the 450BB is ~3 1/8"; the 500/550 is ~ 4 1/8"...fuel taps are on opposite sides...

Here's some quick & dirty measurements...




My 500/550 tanks are identical except for fuel tap mounting; both are K models...The 450 tank is a Black Bomber (65-67) tank...

To use this 450 tank on my 550, I'd have to fab & weld a new frame tab for the rear mount...maybe use eccentric front stub rubber bushings...and shorten the front of my 550 seat...

I don't think I want to do any of that...too much work...it'd be easier to just buy a 450 and mount my Black Bomber tank on it...

...Or sell off the 450 tank...   

(Yo, Bill! Let's talk!)

[puppytrax]

If you shortened the pins (that the rubber mount slide onto) just a little and trimmed the 2 rubber mounts just a bit, it would lat the tank go in place and settle down okay.

On my 500/550's, those two "pins" are actually one long tube through the frame (~4 1/8" long). If it didn't look right (tank angled or too far forward), you could cut those ends off entirely, make a new tube, drill a hole through the frame, and weld the tube in place.

[bill440cars]

      puppytrax,
                 It's too bad that the BB tank won't work for you but, since it won't, a PM is in route, as we speak.

                                                  Later on, Bill

[puppytrax]

                 It's too bad that the BB tank won't work for you but, since it won't, a PM is in route, as we speak.

Bill - Here's one I bid on a couple weeks back...I didn't win...   

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=230094050096





Mine isn't as good looking...tank is stripped to bare metal; some bondo used (obviously, some dents); one chrome panel scrunched; knee pads good; badges on the way...   

Pics coming; camera battery charging...     stupid camera!...