Jeeter
XS650 Addict
Excellent information, thank you very much.My daily rider is a kick-only XS and I've never, even once, wished that it had electric start. They are easy to kick and, if tuned right, will always fire on the first or second kick. I do not have a big bore or high compression so your mileage may vary.
I also have run a 277 re-phase and found it far more "buzzy" than the 360 when going down the road. The 360 crank I'm running now is smooth by comparison. That's not to say that it is actually smooth, because there is no way to make a non-counterbalanced parallel twin run smooth. To me, the 360 has a rhythmic vibration where the 277 had a harsh buzzy vibration. That said, I still prefer a 277 motor to a 360 just because it sounds better.
I have never run big-fin jugs and I've never had the motor overheat. So, it's kind of like the solution to a problem that doesn't exist. I also don't live in the desert so, again, your mileage may vary.
I've watched a number of videos of people kicking over XS650s. They seem to be (dare I say it?) pretty easy to kick over, as long as they are properly tuned. Even though I stand at a towering 5'6" and come in at a massive buck-seventy, I don't think I'll have much problem.
NOW, AS TO THE PRACTICALITY OF THIS CONFIGURATION:
Ok, I've read a bunch of tech stuff in the tech section by this point. It's funny, half of everyone that had an opnion on the 750 (or other larger bores) said that it increased vibrations (offensive vibes, that is). And half of them said it decreased offensive vibes.
What seemed to make the most sense to me (being as ignorant as I am on the XS650 package) was to retain the 650cc displacement, keep the static compression down to "91 octane friendly" levels, and properly tune the engine (jetting, ignition timing, carb syncing, and so on). Do a clean-up on the ports (simply matching the ports to the gaskets .. aka "gasket matching" .. is usually enough), pipes, carbs, cams, ignition, call it done. Oh, and the PMA/Kick-only setup.
My guess is that increasing the power-to-weight ratio will be a far more effective way of going faster with this engine package, unless reliability is of no concern. Hopefully I can get this bike below 350 pounds soakin' wet. If Mert Lawwill could get his iron cylinder, steel side cased Harley down to 309 pounds (wow!), I should hope that I can get this thing down to at least 350.