btrac11
XS650 Enthusiast
Been a long time coming.. I bought this bike 10 years ago, rode it a couple times and decided I needed to make some changes. My brother had a katana parts bike that he didn’t want anymore(complete bike cut in half minus the motor) and I decided that it was going to be the donor for the project. I’ve stared at this thing countless hours and just never had the time to actually do work. Well the time is now.. I am riding this thing this year. I’ve got a lot of ground work to go, but it’s gonna happen..
The basics..
1979 Yamaha Xs650 special- frame and motor
2002 Suzuki katana complete front triple tree and rear swing arm w/ mono shock.
Hughs hand built PMA
I had swapped the front triple tree assembly using tapered neck bearings from the katana to the XS years ago, it sat in the garage like this for years..
Long story short, I got divorced and it freed up a lot of my time..
That’s when I decided to put the knife to it..
I started by cutting off the embossments that positioned the factory swingarm between the frame. I needed clearance as the katana swingarm was approximately 1 inch wider than the factory swingarm.
Once they were removed I knew what my maximum frame width was.. I took the katana swing arm to work and machined approximately a half inch off each side, I had to ream/bore the inside diameter the same amount so that the factory swing arm pivot bearing would mount back in place.
I made a jig from the katana frame to get the correct geometry for the shock mount locations.. After countless times of assembling, tacking in place, cutting back apart, I finally achieved a suitable ride height that favored the chain “sag” on top of the swing arm. I had to use the jig to find appropriate mounting locations and to get the mount brackets fabricated. After hand fabricating the mounts(multiple times) I think I finally have it where it needs to be.. the mounts have been welded to the frame. These mounts are used to adapt the mono shock to the frame..
Once that was all in place I had to figure out the gearing. Factory katana is a 34 tooth rear, 17 tooth front.. 2:1 ratio.. I couldn’t find any sprockets for the katana wheel with a tooth count less than 43,so I decided to draw it in 3D cad and had it laser cut. My current gearing is 18t front 39t rear. I wanted to go smaller on the rear but the chain to swingarm interference wouldn’t allow it. I used a gs500 Cush Drive to gain the offset needed to align the katana wheel to the XS motor sprocket location..
I have never liked how it felt sitting on the bike. It has always felt like I was on it and not part of it. That needed to change. I cut the top frame rails and dropped them roughly 2” to get me closer to the center of mass.. I’m a rather short guy, 5’5” and the bike was always hard for me to sit on and use my feet to pedal around. man my feet barely touched. That is not the case anymore.
I am currently trying to modify the 80’s Harley seat that came on it, I have cut and trimmed it to fit the new frame rails.. still need to find someone to help with finishing the leatherwork.
The current list of “to do’s” consist of:
figuring out the rear brake, the new swingarm takes away the space where the rear brake master cylinder actuation rod used to be.
mounting regulator/rectifier and coil and wiring.
Freshening up the carbs with new vacuum slides
Mounting the rear fender
Finishing the seat.
The finish line is in sight..
Let me know what you guys think..
Cheers!
The basics..
1979 Yamaha Xs650 special- frame and motor
2002 Suzuki katana complete front triple tree and rear swing arm w/ mono shock.
Hughs hand built PMA
I had swapped the front triple tree assembly using tapered neck bearings from the katana to the XS years ago, it sat in the garage like this for years..
Long story short, I got divorced and it freed up a lot of my time..
That’s when I decided to put the knife to it..
I started by cutting off the embossments that positioned the factory swingarm between the frame. I needed clearance as the katana swingarm was approximately 1 inch wider than the factory swingarm.
Once they were removed I knew what my maximum frame width was.. I took the katana swing arm to work and machined approximately a half inch off each side, I had to ream/bore the inside diameter the same amount so that the factory swing arm pivot bearing would mount back in place.
I made a jig from the katana frame to get the correct geometry for the shock mount locations.. After countless times of assembling, tacking in place, cutting back apart, I finally achieved a suitable ride height that favored the chain “sag” on top of the swing arm. I had to use the jig to find appropriate mounting locations and to get the mount brackets fabricated. After hand fabricating the mounts(multiple times) I think I finally have it where it needs to be.. the mounts have been welded to the frame. These mounts are used to adapt the mono shock to the frame..
Once that was all in place I had to figure out the gearing. Factory katana is a 34 tooth rear, 17 tooth front.. 2:1 ratio.. I couldn’t find any sprockets for the katana wheel with a tooth count less than 43,so I decided to draw it in 3D cad and had it laser cut. My current gearing is 18t front 39t rear. I wanted to go smaller on the rear but the chain to swingarm interference wouldn’t allow it. I used a gs500 Cush Drive to gain the offset needed to align the katana wheel to the XS motor sprocket location..
I have never liked how it felt sitting on the bike. It has always felt like I was on it and not part of it. That needed to change. I cut the top frame rails and dropped them roughly 2” to get me closer to the center of mass.. I’m a rather short guy, 5’5” and the bike was always hard for me to sit on and use my feet to pedal around. man my feet barely touched. That is not the case anymore.
I am currently trying to modify the 80’s Harley seat that came on it, I have cut and trimmed it to fit the new frame rails.. still need to find someone to help with finishing the leatherwork.
The current list of “to do’s” consist of:
figuring out the rear brake, the new swingarm takes away the space where the rear brake master cylinder actuation rod used to be.
mounting regulator/rectifier and coil and wiring.
Freshening up the carbs with new vacuum slides
Mounting the rear fender
Finishing the seat.
The finish line is in sight..
Let me know what you guys think..
Cheers!
