Hello, I have what I consider to be a strange issue with my ’88 xr250r which is confuising me. When the bike has been un-used for a very long weekend or longer, sometime, when trying to start it has zero compression. After kicking for 20 to 30 times, compression slowly returns until it runs(badly) then after a couple of minutes or riding it’s back to normal with good compression. I use the bike everyday for commuting, it uses lots of oil through leaks and burning. These will be fixed one day. Promise. Possible causes for intermittent low compression. 1. De-comp sticking on. The bike has no de-comp cables, all removed by previous owner. Only control I have over decomp is by twisting the end of the cam sticking out of the head. This was in its normal position when I lost compression. 2. Rusty valves. Can valves rust this quickly? 3. Sticking valves, I would have thought kicking the bike over would instantly fix this. 4. Knackered rings. Could an oily bore be disguising knackered rings so only when the bore is dry do I loose compression? 5. Knackered head-gasket, again, can daily use disguise a knackered head gasket. Can a head gasket be so bad that you lose all compression? Any advise on the above would be much appreciated. As I use the bike everyday I don’t want to strip the engine down until I have a fairly good idea what needs fixing.