78 KZ/GSXR 650 Street Fighter Project Chassis

Hey everybody, moving along on my project...It's a 78 KZ650B2. I have been working on it for about 5 months now with unbelievable help after many hours spent researching KZR's threads. Before I had general questions about mods and now that I am making progress I have some more specific questions. First here is a pic of the project of how it sits.


To get a general sense of what I'm doing....I swapped steering stems and have installed a 2001 GSXR750 front end. For the rear I fitted a 2001 SV650 swingarm, wheel, brake, etc. I used had the original KZ swingarm bolt machined/grinded to fit inside the SV sleeve and bushings which ride in roller bearings. I plan to use dual shocks and keep the motor stock with pods and a 4 into 1 exhaust.

Now my first question concerns the swingarm: When installed the bolt, sleeve, bearings, bushings fit perfectly. However, between the swingarm tube and bushings themselves and the frame there is about 1/8 inch side to side free play. I plan to have thin spacers/washers machined to snug up the gaps on either side. My question here is how much wiggle room do I want to leave in there? Should it be nice and snug or should there be a little side to side free play?

Next, is my biggest concern/question. With the modifications to modern running gear/tires/brakes...I understand that for starters I will need to upgrade to tapered steering head bearings, as they can bear more load than the standard ball bearings in a cup. Now to make the ride safe and functional as a mild street fighter, what mods should I employ to the frame? I have read alot of threads and found resources for bracing the Z1 frames, and understand that many of the same ideas apply. However, my 650 frame was made alot different from the older 900's. For one my frame has some triangular gusseting on the headstock and one small connecting brace about 7 inches below the steering tube.


..haha a funny face there

Should I leave the gusseting and add some cnnecting bars around where the coils mount to further tie those 3 tubes together? Should I cut out the old gussetings and replace with a different gauge/design?

I will post some more pics of areas that may need brace bars or gusseting:




I know for sure that I need to add a bar on the back where I shortened the subframe.

Keep in mind with recommendations that this bike is not going to be a 100+hp wheelie monster, I mostly do around town riding and love the woodsy twisties and back roads here in southwestern Ohio. I just want to make this thing as safe and functional as nice to look at when I am all through. BTW all welding and machine work is/will be done by local pros not by myself...I am doing everything else. Thanks hope you all dig it!

Great project you've got there and welcome to KZR. The 650's frames are pretty strong, the only brace you may want to add would be a cross bar above the rear of the motor. Here's a pic of my frame with the bar added.
Mark

Yep. That's what I'd say, too. That rear frame brace is important. You can even "X" brace it to assist in resisting tortional twisting caused by your new beefy running gear when making transitions in your twisty riding. The 'sub-frame' brace you spoke of isn't clear to me; but the sub-frame isn't going to have much of an impact on handling, as long as everything is firm. Oh, you want your swingarm to "fit" snug.
IF you need more bracing there is more to be done, but I don't think you'll need it based off your description of the motor...but, if you are a rocket in the corners and it starts to get 'upset' there are still bracings you can take, but I'd just go with what you're doing...which is GREAT stuff!
-KR

PS> You're going to make a build-post in 'Projects' too, aren't you.

Thanks for the tips! I have a build thread in the projects section but haven't updated it in awhile because I have mostly just been collecting parts and doing research. When it comes time to line up the sprockets...can I machine the rear sprocket carrier down on the outside or do I need to do it from the cush drive side?