Topic: '77 CB550F Rear Wheel Hub - really need some help

[vincentlefre]

Hi all,

I'm currently at a crucial stage on a 1977 CB550 F2 project and I've had a few issues with the rear wheel hub. Upon dissasembly I found the usual cracked and ovaled brake liner which I'm in the process of replacing but I also have some issues with the sproket/drive side of the hub. Without going into too much detail I'm basically after a few measurements that I'm unable to find in any manual or guide. I need to know what the following measurements are supposed to be from someone with a hub in good/original condition. If anyone has this information or can find out for me I might be in with a shout of repairing it.

Please see the image below for what I'm after. Any help you guys can give me will really help.

[LesterPiglet]

I'll be able to answer that tomorrow. I have a spare hub in the garage I need to dig out.

[vincentlefre]

That'd be great mate, thank you.

You're not looking to sell it are you? I'm a bit concerned that mine might be beyond saving.
The rockers you sent are fitted in my newly reassembled engine with many thanks!

Let me know re: measurements

[LesterPiglet]

Sorry Vince, as you say they crack and oval so I'd like to keep it just in case.

Measurements are 79mm for OD and I get 79mm for inside as well. I notice it has a sleeve around the OD part.

[vincentlefre]

Thanks for the reply mate. My problem is essentially that I have way too much play between the two parts and I suspected they'd both been machined at some point to clean them up and then fitted with some nasty looking shims between the two pieces. Based on your measurements (did you use vernier calipers?) my suspicions would be correct as the OD measurement on mine is 78.5mm and the ID measurement is 79.3, i.e both faces have been machined. I'm interested by what you're referring to as a sleeve on the OD part, can you provide a photo of this? The exploded drawing shows nothing of the kind. Does it look like someone might have done a similar repair on your hub?

What I really want to confirm is should these two parts be a 'bearing' fit with one another? If so then I need to work out a way to take up the slack that is present in mine.

Anyway, thanks again for your help, any further info you can give me is really gonna help.

[crazypj]

I'm pretty sure the original sprocket had a bushing in it?
Aftermarket sprockets don't come with bushing, it's probably been missing for years.
 I would just get a sleeve fitted

[LesterPiglet]

The above picture shows the sleeve . The outermost part you wanted measured. I did use verniers but the battery is shagged so I used the old fashioned method.

[LesterPiglet]

[vincentlefre]

Thanks for the replies. So in answer to the key question, these two surfaces are suposed to bear on one another without any slack correct? And I may need to machine a sleeve to take up the slack present on mine?

[LesterPiglet]

That seems to be the case.