Rebore

After having decided on the full strip down and rebore, I obviously needed to remove the head, barrels, and pistons etc.. This proved pretty easy (as I remembered from previous lives), I still managed to round off a couple of screws – one holding the two power valves together in between the cylinders – particularly difficult to get a drill to, and the second was holding the power valve pulley in place, this one slightly easier to drill out. Anyway only standard for a Jap bike of this age (even new for that matter!). After having seen the number on the tops of the pistons +25 I assumed that I had some rebores to go before renewing the sleeves, however I assumed wrongly as the +25 turned out to be +75 (really badly etched) after measuring. I was really lucky the guy in the rebore workshop measured this before ordering the pistons, otherwise I would be selling perfectly good pistons on Ebay! Interesting to note that Yam pistons only go up to +50, and yet Wiseco’s go up at least to +150. I am using +100's, I only hope the longevity of the sleeve is not effected by the extra amount taken from it.

Hopefully I will get time to order my seat unit from Poly26 this week, so I can get them all painted together. Which will be the next task.