I have three XS650s (a 76C, a 78E and an '81SH and over the years, I have been into the clutches on all of them. I discovered that in fact, my bikes have a 29mm, a 30mm and a 31mm clutch hub nut (i.e. each has a different sized nut) and so it appears that someone has either been in there before, or Yamaha was shopping around for fasteners and used whatever they got the best deal on.
I am sure there is a
standard size and I think it is 29mm - but only one of my bikes uses that particular size.
When I ran into this situation, I went to Princess Automotive (the CDN counterpart to Harbor Fright) and they had open stock on all three sizes for around, I think $9-12 each. Sooooo, I bought a set running from about 27-34mm just so I wouldn't be caught out. It cost me about $100 or so - but
waaaaay cheaper than paying someone else to work on my bikes.
So, if you are going to venture inside the RH side engine case cover to mess with your clutch, here is my advice:
- Get a JIS impact driver for the six stock clutch basket screws. If they are not chowdered already, using a regular screwdriver will likely do so and if they are chowdered, you will NOT get them off without an decent impact driver. Once you have them off, consider replacing them with a set of XS Performance socket-head cap screws (SHCS = Allen screws) - these are MUCH easier to deal with and as long as you use a good Allen key on them, they will not strip.
- Wait until you get things opened up and can see what size the big clutch hub nut is - then measure it and go buy that sized socket.
- Use an electric buzz-gun to get the clutch hub nut loosened.
- Use a torque wrench to put everything back together.
- Those interesting looking clutch holding tools are a waste of money. Just put the bike in gear and have a helpful assistant stand on the rear brake while you torque the hub centre nut.
Pete
