1981 KZ650 Frame loop

Going to install a frame loop for the seat for this cafe racer build. I have a 1981 KZ650 and the bars measured roughly 9.5" outside to outside. Has anyone installed a frame loop and have any advice?

The closest mm would also be appreciated they have 230, 235, and 238mm on eBay but I'd like to get the best option before I wait on that shipping time.

I haven't done this, but before buying anything or making any cuts, I would measure the heck out of the frame & seat etc,
and watch some youtube videos. Also, dimecitycycles usually has good pics for stuff like this, maybe some videos.
example vidoe search >> how to install a motorcycle frame hoop

Frame bracing. Depending upon what you cut off, you may need to add some frame bracing/cross-bracing, especially in regards to the shock mounts which endure quite a bit of force, especially if they bottom out from a bad pothole. there are some poorly done frames out there.

A pic, since I have the same motorcycle.
1981 KZ650-CSR w KZ550-Ltd wheels. KZ750E mufflers. Emgo Euro bars. 1000J Mirrors. K&G luggage rack.

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Thanks for the response! I've been looking into it but need to figure out the best options for seats as well. Making a seat pan, some foam, getting it wrapped. Or just ordering one off eBay and building the frame loop to fit properly. We'll have to see here soon. Got the GSXR front end and conversion kit with new stem, bearings, and triple tree top. Can't wait to get started!

Nice bike it's still mint! I have a lot of stock parts I'm going to need to get rid of here now too hopefully people here can put them to use!