I did read that the engine is supposed to be warm and throttle held at wide-open when compression testing, but the carbs aren't mounted. They came with the bike, but in a box.
Don't fret about the carbs not being mounted, just so you can hold them wide-open to do the test. Actually, having them off is the best, but very few mechanics want to go through the hassle of removing the carbs off an hot engine, so we just hold the throttle open to make sure the engine can breathe as much as possible.
And, with the carbs already off the bike, that is the PERFECT time to rebuild them. Do NOT waste your money on rebuild kits, though. 99% of the time, all they need is a good "strip and dip" cleaning, followed by a new set of o-rings and possibly new float bowl gaskets.
The "strip and dip" procedure is shown
HERE. You will need a can of Berryman's or GUNK brand carb cleaner dip (about $20), a set of o-rings from
cycleorings.com and I would recommend also getting the intake boot o-rings and the stainless bolts that hold the boots to the head, also from cycleorings.
Speaking of warm (and this may sound stupid), but I've never owned an air-cooled vehicle; how do I know if its overheating? Does it just quit? Lose power? Can it overheat?
Yes, it
can overheat. Depending on how badly it is overheating, you will notice a loss of power, which will likely be due to the pistons expanding to the size of the cylinders, instead of their usual clearance. As long as you have your carbs jetted for your intake and exhaust plumbing (stock is pretty close to "best"), there is little chance of overheating. Just try not to have the engine idling for extended periods of time, especially after running warm, like a freeway run that suddenly comes to a traffic stop.
Finally, the time will eventually come to replace the worthless tires. Anybody have any favorites to recommend?
If the tires are already "worthless", that eventuality has already happened.
If you see any cracking in the tread or if the tires are more than about 5 years old, they need to be replaced before leaving your driveway.
Read the date code on the sidewall, you may be amazed at how old they are.
Favorites? That depends on your budget and your riding style. For casual riding, but with a surprising amount of grip, many of us are using Shinko Tour Master 230. About $130 per set, shipped to your door. You will have to install or arrange installation.
For a bit more grip, I think the preference is toward Avon Road Riders or Pirelli Sport Demons. A bit more money, a bit less life, better performance while they last.
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