Topic: '72 CB750K3 Seat Rail

[Beav068]

Hello everyone.  I have a problem relating to a seat rail.  I just purchased this rail on Ebay thinking it would fit (as it was advertised for my year of bike) but I cannot see how I am supposed to mount my rear turn signals.

The first picture is what is currently on my bike.  The second one is the new rail.  The third is my attempt to show how the holes match (or don't) with what is there now.

Does anyone know or have pictures of how this should all mount up?  Unless I am wrong, the mounting bolts that I see on toward the middle rear of the rail do not match up with what is on my bike now.

Any suggestions?

Thank you,

Tim

[sparty]

First you have to remove the current rear sissy bar and its bracket.  The rail that you just bought should mount in the rear frame holes - The rear marker lights will then mount inside those holes that you see on the rail.  Just look at a picture of a stock CB750 of your year and it will be easy to see.

Sparty

[Beav068]

Sparty,

Thanks for the reply.  The frame that you can see behind the existing sissy bar is PART of the sissy bar (welded).  If I remove it then there is nothing to bolt into in the holes on the new bar.  The front is easy enough, mounting at the upper rear shock mounts, but from there I can't see how it is supposed to mount.  The only thing behind that hole in the new bar is fender.

Also, the signal mounts I have now are a two-hole setup with the wires going through one hole and a screw holding the bracket onto the frame mentioned above.

Anyone else have any suggestions and/or pictures to help me out?

Thanks again guys (and gals)!

Tim

[Beav068]

Anyone??  Anyone??

Nah, I'm not trying to be pushy...really.  But I mean, seriously, look at that damn sissy bar!  I have GOT to get that fugly thing off of there!!

Tim

[kghost]

First....its hard to have a 72 K3......maybe you have a K3 built in the last half of 1972.

I have three or four (really I can't remember) K2's all built in the first part of 1972.

Your correct in that the grab bar mounts to the shocks in the front.

Sparty is correct in that the hole in the grab bar is for a bolt that goes thru the rear of the frame and into the fender.

On the K2 bikes the grab bar has a tab to which the turn signals mount.

See the link below to my gallery as to how the turn signals / grab rail mounts on the K2 bikes.

http://www.sohc4.us/gallery/v/members/personal/kghost/black750/

Image 1689 is the best

[dusterdude]

i have a grab bar a lot like yours,however mine has a bracket welded on for the turn signals,it appears yours doesnt.you could always scrap the signals couldnt you?

[Beav068]

Kghost,

I'm sorry if I misspoke.  I was under the impression that '69=K0, '70=K1, '71=K2 and '72=K3.  Apparently that is not the case?  Mine was manufactured in 09/1972.  Could I beg you to measure the distance between the shock mount hole and fender mount hole on your bar?  Your picture leads me to believe that the rear hole on the bar you have lines up with the bolts holding the fender on.

Dusterdude,

Scrapping the turn signals really doesn't appeal to me as people have a tendency towards rear-end collisions here in Oregon.  Not sure why, but I would prefer that they have a turn signal AND brake light to help them see me when I am stopped.

Anyway, for now I have just bagged the seat rail (I think it is the wrong one, as the rear hole you see extends well beyond the existing fender mount bolt) and fabbed up a mounting tab to bolt into the rear fender mount bolt behind  and below the seat.

Thank you all again for all your help.  This site, and the community of SOHC4 enthusiasts that make it work, is an absolute Godsend!

Tim

[kghost]

I measured my K2..........

Actually I measured both the K2's I have at the house

Hole to hole is approx. 7 inches

I prolly have one out at the shop if you need one

[mrbreeze]

Sounds like you might have a 77-78 grab bar.I bought one on ebay a couple of years ago and came to find it is a different style than the pre 77 bar.Also ,the fender and seat are different.

[Beav068]

MrBreeze, you are probably right.  This one measures 10 inches from center hole to center hole.

Kghost, if you have one in good shape, that would be great. It would be even BETTER if it has the signal mounts and everything. Does anyone need the one I have, or would you be willing to trade?

Thanks again SO much for being such a great group of guys!

Tim

[kghost]

I'll look at the shop the very next time I'm out there

[Beav068]

Mr. Kghost sir,

Did you happen to check out the shop? 

I feel like Oliver Twist. (May I have more please sir?)

Beav

[kghost]

Haven't been home since monday I'm being held hostage in Pontiac........

Soon as I get my bird home I'll get out there and have a look.

Sorry for the delay

[Beav068]

Don't sweat it at all man.  When you get home, kiss your wife/girlfriend/*shudders*boyfriend, whatever.  Have a beer, take a nap and/or shower, and THEN think about looking.

Not worth hassling you over man...

Tim

[kghost]

Don't sweat it at all man.  When you get home, kiss your wife/girlfriend/*shudders*boyfriend, whatever.  Have a beer, take a nap and/or shower, and THEN think about looking.

Not worth hassling you over man...

Tim

Well I drank 2 bottles of cheap and nasty australian wine. Wife? I'm not her favorite person. Might be why I drank the wine...I forget 

I don't like women...but I like men even less  (not that there is anything wrong with that  ) so no shudder required.

I looked at the shop and I have two. One from a 10/72 build and one from a 10/74 build. They appear to be the same.

I also have a oddball one that is 7 1/2 inches with no turm signal mount tabs...

Do you need lights with that Mr. Twist? Lemme know what ya need and I'll pull the one that looks the best.

[Beav068]

I have all of the stock lights-n-such, so just the rail is all I need.  Thanks SO much mate!  Let me know what I owe you, and we'll square things.  If you need a sissy bar, custom (touring) seat or longer (later year model) grab rail, I'd be willing to do some swapping.  If not, ebay it is.

Thanks again!

Tim

[kghost]

Well if ya tell me where to send it......

That would be helpful. PM me