Engine warmups - to do or not
If the pistons warm up too fast on water cooled motors, they tend to create too tight of a clearance between the cylinder wall and the piston. This could lead to scuffed pistons or worse. This is called cold siezing and is most prone to happening in two-strokes but that doesn't mean that it doesn't happen at all in four-strokes.
I remember reading something in one of the motorcycle mags a while back (don't want to date myself here) that you should only warm up your bike enough to be able to ride away with "acceptable" throttle response even if still on the choke. Then, turn off or reduce the amount of choke as required as soon as possible. Reason, if I remember correctly, was that while running rich for long periods of time, the engine will build up lots of carbon/soot. This stuff will cause excessive wear on the cylinder walls as well as contaminate the oil, etc. But then my bike never needs choke, which helps in this circumstance
What I've read suggests that warming up may actually be detrimental to engine life. As your engine cools water vapor condenses in the crankcase, where it becomes acidic from contaminants in the oil, mostly from combustion byproducts. On cold startup that acidic water is circulated in the oil system, which causes pitting of cylinder walls, bearing surfaces, and the like. When the engine reaches operating temperature the water is evaporated, and the contaminants are left in the oil, which doesn't become acidic. Thus, the faster you can warm your engine up (without getting metal-to-metal contact because of low volume from the oil pump due to high oil viscosity), the less wear you'll accumulate. I don't know if there's any truth to this, but I've had good success with engine life without warming anything up.
Cleaning Products
I've started using Honda's Spray and Polish. If it does everything (clean, polish, protect from UV) that it claims to do to all the different parts (fairing, chrome, plastic, rubber), it's got to be a winner. I can attest to it's cleaning ability.
Chain Maintenance
For those not familiar on how to use WD40:
Clean your chain with WD40 or kerosene (kerosene is cheap), use plenty of clean rags. This removes the old oil and crud. Do not use a wire brush, you don't want to damage the sealed O-rings which hold in the factory applied lube for the pins.
Once chain is clean (to your liking), take the bike for a short ride to warm up the chain. The warmth will allow the WD40 to set better.
Shut your engine off, put the tranny in neutral (clutch use optional:)), spray the left side plates and the right side plates of the chain, then the middle. Spray liberally but do not over saturate the chain to where it's dripping WD40 everywhere (some dripping is to be expected and acceptable). DO NOT wipe any of this initial spray off! This is important. If over spray is a concern (and when is it not) use a rag to protect where you spray on the chain. Slow and sure is the way to go. It gets faster as you get the idea.
Allow the WD40 to set as the aromatics will dissipate. Let the bike sit for a while, preferably overnight. Once the WD40 is set you can ride the bike. Some spray will get onto your rim, just clean up after your done (just like sex:)).
Remember: WD40 lasts about 400 miles. Lightly respray as needed and let it dry. DO NOT wipe it off! This is the important part of why some chains show some rust with WD40. The product can't protect the plates if it's not on the plates. One of my riding friends was doing the same thing once he too switched > to WD40. He would apply a light coating of WD40 and then immediately > wipe it off. NOT GOOD. Allow the spray to set.
Once you get it, the chain WILL stay cleaner and quieter. Subsequent clean up will be much easier and less time consuming.
To me I would add the following: every so often I use a toothbrush with the kerosene, when I'm feeling extra anal, the kerosene works great for cleaning the gunk off wheels, swingarm, rear hub, etc.
The other side................
In sensitive areas such as high precession/speed/load bearings or near soft sealing material such as most O-ring compounds, and even harder materials like carbon, teflon, ceramic (for high pressures) and so forth -always use synthetics. Reasons: WD-40 (and all other dyno based lubes) are inherently dirty, not to the naked eye, but dirty just the same. Synthetics are much cleaner originating in sterile environments. Also, many O-rings compounds do not agree with dyno base oils. In tight tolerance spots (between high pressure seals, or O-rings and adjacent metal) grit can score away at hard seals and destroy soft ones -either way, the sealing ability diminishes till gone altogether. When designing around O-rings, metal must be very smooth and free of scratches and tool marks (more so for dynamic applications than static). Many will say this is nit picking and may only prolong O-ring life by 1-2 years on a chain -but it would also prolong the chain by 3-4 years. O-ring chains come pre-lubed on the inside, O-rings seal lube in and dirt out. Lubing O-ring chains is to keep the O-rings from drying out so they can continue sealing. At a point, with proper procedure, the o-rings will be worn enough that getting lube past them to actually lube the chain is possible -at this point, the lube is for the chain -not the o-rings, and must be suitable for the job.
Tyres
Tubeless tires can often be patched from the inside. I've patched cycle tires at least twice and used them without issues for long periods thereafter. There *are* patching kits sold by mailorder companies, do a search on the web and find some motorcycle accessory companies for sources. www.compacc.com comes to mind, tho I have no personal experience with them. The process is fairly simple (to describe..) - with the tire removed from the wheel, remove the offending object if still present. Use a rasp tool (usually included in repair kits, basically a very rough pointed cylindrical file, thinner than a pencil) to rough up the hole- as though you were re-puncturing the tire, so the 'walls' of the puncture hole get roughed up. Dust off the spot or wash it, let dry and apply rubber cement to the inner surface of the tire around the puncture. Put a patch over the hole - patches vary, I lean toward the kind that have a nub in their center to fill in the puncture hole - and apply pressure to help the patch adhere. Professional shops will also first rasp the inside surface of the tire around the hole to provide more adhesion for the cement/patch, and will use a tool like a dull pizza cutter to roll over and firmly adhere the patch. Let dry and remount the tire. Refill with air and hold the patched area under water to see if any airbubbles betray an incomplete patching job. Repeat as necessary.
Sealants
I have noticed some quetions about if and how to use silicone sealing for the motor on this list. I guess this is an answer to it all. Silicone seal is only a temporary fix and shouldn't really be used anywhere on the bike. I wrote about it some time ago at the Sabmag BBS and now I do it at this list as well so everybody here can awoid the same dissaster that happend to a friend of mine because of the use of silicone sealent. Don't ever use silicone to seal motor covers and deffenitly *not* for the crankcase halfs. This friend of mine did, (ok he used to much of it, but no one can say how much is to much) and he had a big time motor dissaster since parts of that rubber-like-silicone-junk came loose and clogged his oil channels. He had to replace the entire cylinderhead (an inline four) since his cams wore down, as well as the heads, cam bearing surfices and everything. The only thing left of it was just junk, (I saw it, and it looked like somebody had used a grinding machine on the head) the only thing he could do with the head was just to trash it. That's what I call a VERY expensive experiance. For crankcase assembly is "Kawasaki Bond" the right stuff to use. It's a special glue with aluminium powder in it. That's what the factory's are using and I guess Dave Dodge uses it as well, or maybe he uses "Honda Bond" but it's the same stuff only with a different name and... more expencive ;-)