CB650 motor in CB550 frame

[Ride509]

Hey guys i am currently in the middle of a build. which started as a 1980 cb650c. now i am so deep into this build that i would rather not have to deal with the dip in the 650's frame. i have a motorcycle scrape yard near by and am able to get eithier a 79 cb650 frame or a 70's 550 frame. i am just wondering which frame is better i have seen that the 550 is better but i am not sure why.
Thanks

 

[cxman]

the 650 pretty much bolts right into the 550 frame you just have to mess with one rear frame mount

so its up to you

 

[Ride509]

Is there any benefit for the 550 frame over the 79 650?


Sent from my iPhone using Tapatalk

 

[Tune-A-Fish]

I would say there's not a lot of difference, both are single 2pc stamped steel backbone. Is the swingarm longer/wider on one or maybe the head stock is raked more than the other??

Someone will have this info, but both should be fine for cruising and neither are really a cafe frame... superbikes are some wiggly bastards so if you ride the new box framed bikes and look for that rigid hard carving ride from the noodle frames these cb's have you won't find it.

Good luck with the build, looking forward to watching the results.

RD

 

[Ride509]

No I have never ridden anything other then my cb660 and my 04 883 sporty . It's kind of like why I don't go shoot new bows that come out because I will want one . Till then I am very satisfied with my noodle frame


Sent from my iPhone using Tapatalk

 

[Bert Jan]

650c has a different frame as as 550. Engine will fit though, unless your bike has cardan. Cb650c came with chaindrive and cardan. Wich one do you have? Cardan frame is different and will require moooore work, especially cause youll need a different swingarm and rearwheel

 

[Ride509]

I have currently a 1980 cb650 custom . I am looking at getting a 79cb650 frame or a 70s cb550 frame . Both look the same but I am not sure of any inherit differences with frame strength , neck angle. I know the cb650 has a longer swing arm but most things do swap over. I just don't want to buy one and realize the other was the better choice . I know the 79 cb650 frame has a removable frame section to help with getting the motor out easier .

Also does anyone know any good references to help stiffen a frame . I understand that when making one section stiffer you basicly transfer the stress to another section .


Sent from my iPhone using Tapatalk