TOPIC:

Smartpeople, I am about to start the assembly of the "wifes" 550 after too many years of restoring it. All parts have been refurb, bagged and tagged. However, I would like to upgrade the swingarm, as it's a pitiful farty little thing. Anybody know if the Zephyr 550 swingarm will fit? I'm hoping for a less involved installation than the ZRX to GPZ11 swap.

I have to get this done before I can start the "newly" acquired H2 project...that ya'll made me buy

Thanks
577Nitro

I have no idea what 550 you are wanting to put the swingarm into, but I can fill in some of the info you need.
The Zephyr 550 swingarm is right at 9” wide at the pivot. (I’m almost positive the zrx is 9.25”)
It’s roughly 21” from the swingarm pivot to the rear axle with the eccentric centered.
The rear of the swing arm is 11.5” wide.
You will save yourself an insane amount of work if you get the matching wheel, hub and brake assembly.
You will need an offset front sprocket and a longer chain.
You may need to machine up a new pivot collar and bearing races depending on the size of the 550 pivot bolt. (See the build link in my signature to see how I had to do mine)

Daftrusty wrote: I have no idea what 550 you are wanting to put the swingarm into, but I can fill in some of the info you need.
The Zephyr 550 swingarm is right at 9” wide at the pivot. (I’m almost positive the zrx is 9.25”)
It’s roughly 21” from the swingarm pivot to the rear axle with the eccentric centered.
The rear of the swing arm is 11.5” wide.
You will save yourself an insane amount of work if you get the matching wheel, hub and brake assembly.
You will need an offset front sprocket and a longer chain.
You may need to machine up a new pivot collar and bearing races depending on the size of the 550 pivot bolt. (See the build link in my signature to see how I had to do mine)

Thanks for the info, exactly what I needed. It's going on a 1981 GPZ550.

577nitro

Hi, I’m interested in doing this same swap. Did it work out ok?  I’m looking for some info on the things I’ll need to consider. Many thanks