Hi,
I have started a build on a 78 KZ650 that was mostly beyond restoration, It was sitting in some over grown weeds for over 10 years. The motor still turns and has compression, The frame, tank and some plastics I can save. The shocks, front forks, wheels and tries are junk along with most of the wiring. I had done a lot of research before starting the work and everything I found on this topic had me concerned, I just wanted to give this bike a new life so I went at it anyways. I picked up a parts bike for cheap, A 2000 YZF 600r for $50.00 that was missing all it plastics but had everything I was looking for. Now this may sound wired but it was nothing as explained, This swap seemed to be easy and that was unexpected. I am a steel fabricator by tread and I do have a full shop to work out of but no machining tools, Hence my concerns. I was able to install the YZF front forks for the cost of new stem bearings as the stems was the correct length. I did a mono shock conversion using the YZF swing arm and shock, The YZF pivot point uses the same size bearing as the KZ and the O.D. of the pivot bolts are the same, I only had to shave a mil. off of each frame boss at the pivot point as the OE KZ swing arm was 2 mil. narrower than the YZF swing arm. At this point I fabricated mounting tabs for the rear shock and set it to the exact angle and location as it was in the YZF and tacked it in place. I no that I need an offset sprocket of about 5/8" to 3/4" and may make something out of some old sprockets to test exactly what the offset is. I had never heard of anyone using a YZF to do a swap like this and maybe I'm the first but it just seemed way to easy and that has made me nervous, I feel like something is wrong. There was no machining anywhere, I didn't even need to relocate the battery. I haven't full welded any tabs yet, I'm hoping someone might be able to either restore my confidence or point out what may be wrong with this build. Thank You for reading and I'm looking forward to any response.