Piston skirt length

Irristeve made an important point on the rear tensioner on that big-bore big-fin cylinder kit. For those of us with older engines considering that kit, need to get the newer/later type camchain tensioner parts. The tensioner body isn't needed, it's part of the cylinder casting, but need the proper length angled type tensioner bolt and plunger...
 
Irristeve - good info. I've read a little about the issue with the cam chain fitment, but not enough to know if it is/was a problem on all the 750 kits, or just some, or some particular cam chain manufacturer or cam chain guide compatibility, or just individual wrenching skills... kindly post back your results.

Racerdave - If you get the time, it's worthwhile to peruse the Mos2 stuff. 5 to 10 times the ...slipperiness of oil, stable up to higher temps than our engines will ever see, really thin, and really hard. As I indicated a few posts back, I'm not sure how much the extra slipperiness compensates for the higher loading on the shortened skirts. Hopefully some others can/will chip in regarding how many miles on their Mikes/Wiseco 750 kits they have, and if torn down, what shape were the pistons. Irristeve indicated his looked good, but that was only 15000 km; call it 1000 miles. If I can't get 20,000 to 25,000 miles on an engine with a 750 kit (and oil cooler, regular maintenance, etc), then I'm going another direction. I'm simply looking for old school, reliable, somewhat classy, with a little more performance, daily rider. If I wanted to wrench all the time to maintain a high performance bike, I woulda bought a KTM...

While the 700 upgrade with stock barrels would solve the cam chain issues, the enlarged fin area of the 750 kit is enticing; and 100% functional. A long time ago, I went from a 650 Triumph Bonneville to a 750 Norton. That 100cc difference to performance was definitive. IMO, the money expended to performance gained ratio of the 750 kit is better than the 700 kit; assuming it is just as reliable, or really close...

Regards.

Edit - Looks like Two has resolved, I think, the cam chain issue. Hopefully this will assist Irristeve.
 
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I just read the 1st couple pages of the thread about long rods.
I don't see what it is. does that mean that the pin connecting the rod is closer to the top of the piston. How does it change the engine, what is the desired result?
 
Installing longer rods moves the wrist pin higher up shortening the piston compression height and can lighten the piston,just depends. Yamaha used three different rod lengths with the 533 being the longest factory long rod but you also have the the Honda CR500 144mm rod and Kawasaki 145mm rod which require a custom piston. As far as results,that depends on what the intended usage is ,there are just too many variables to factor in. One of the
biggest advantages of a longer rod is that power doesn't nosedive over past peck as a short rod does,extending the power surge and RPM but there are other factors and you need to google them and go to Speedtalk forum to educate yourself on the subject as it can get deep. There will be some who'll preach there are no benefits to be had and there are others like myself who say otherwise. The biggest advantage to use a long rod in the Xs racing
is to cushion the explosive low to mid range power to gain traction.
 
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