81 cb650 custom, on a 79 cb650 frame

[ScrewyLouie]

Hello all, I am new to this site, decided I should join, as I am building a cb650 cafe bike. It started with a free 1981 cb650 custom, that was really really ugly. After ripping it apart i realized that the frame (RC05) is no good for the cafe style. I bought a 79 cb650 frame(RC03) with title, and started the rebuild on this. I have a blog for pictures and info:

cb650cafe.wordpress.com

[Geeto67]

why didn't you buy a cb500/550 frame? your cb650 bolts to that as well and there is way more aftermarket support for the cb500/550 than the 650.

Also, the cb650 frame in general is just shit. it may not have the pressed steel backbone of the earlier bikes but it was not setup as a performance bike. people race cb550s and 500s, haven't seen a 650 on a race track ever.

[kenessex]

There was a guy that used to race a CB650 in the early 80's in the midwest. It went ok, I seem to remember him finishing well but not winning. I don't remember who it was, but it may come to me. I think the 650 will be ok as a cafe, but there are better choices for a race bike.

Ken

[ScrewyLouie]

Geeto67:
I have absolutely no plans on racing, I am just building a cool looking cafe-styled cb street bike.
Gosh this being my first post I didn't think I would get such negative response... I guess we will see how sweet this bike will be when I am finished.

-cb650cafe

1979 cb650
1972 xl250

[kenessex]

Don't worry about Geeto being negative, he just comes across that way on the interwebs, in person he can be a dick, too. However, he will also help you out with parts and info, if he can. He is also right, in that the CB650 frame is the worst of the lot as far as what your engine will fit in. But for your intended purposes, it should just be fine.

What are your plans?

Ken

[ScrewyLouie]

So what is it that makes the 650 frame so bad? The 1979, which is drastically different than the rest of the years, seems to have almost the same geometry as the 550 frame...
I actually locally traded the original seat and sissybar for the 79 frame, with a colorado title, so that worked out well for me.

Anyways, I plan on getting a nice cafe seat, and attempting to relocate the battery and wires into the hump. I was going to get some longer cb750 rear shocks to raise the rear end a bit. The tank is also from a 76 cb750 I believe.. I found some perfect wire wheels for it at a local junyard for $250. Once I have the bike built the way I want it, it will be taken apart for powdercoating and paint. So far I have spent less than $400 on it...



This is what it looked like when I first got it... sooo ugly

[kenessex]

Sounds like a good plan, to me. I suspect the spoke wheels will require some spacer work in order to fit, unless they are from a 650, too. The tank looks like it might be from a CB550F, but I am not sure. The 650 frame was somewhat heavier than the CB500 frame which was the lightest of all.

Ken

[ScrewyLouie]

So yeah, the wheels that I found are from a 650, so they should fit perfect. I am still looking for a petcock, and yeah i have seen a couple of 550 tanks that look exactly like mine, maybe thats what it is. I am going to get this bike all put together and running/driving well, then take it all apart to powdercoat frame, and paint the tank and new seat. Then bead-blast the engine, and fabricate my own taillight. I am hoping to get some custom mufflers welded onto the original header pipes, which aren't in bad shape...

[ahcb650]

Nice work, cb650cafe. I also own an 81 and want to find a frame to pretty much swap everything into, and get a nice cafe tank and seat.

Geeto67:
Is this pretty straight forward, or does it require a lot of modification and customization to fit everything?
I am pretty new to motorcycle, and I want to know what kind of shit I am getting myself into.

[ScrewyLouie]

I'm pretty sure the 650 engine will mount up to the 70s 550 frame, as long as you have the 550 mounts to go with it...
Dont know about the cb500 frame