hi I had a Yamaha tr1 fully enclosed chain case on my Yamaha sr500 ( I tried a peter furlong case too complicated lots of parts was a hassle in the front garden let alone at the road side) ,the tr1 case took a lot of hours to make it fit but what a difference ,I was using standard heavy duty chains ( before x-ring chains) which I would get about 12,000 miles with lots of oiling and adjusting ,I then put a new standard heavy duty chain in when I put the chain case on and got 36,000 miles with hardly any adjusting and just take the chain off clean and boil in chain oil maybe twice a year (I was doing around 12,000 miles a year then) the rear wheel would stay cleaner as well ,it always gets me how in the bike world we seem to treat the effects and not the cause, example in the car world cv joints ,open to the elements so clean and regrease or cover up with a boot to stop the grease being washed out and contaminated with dirt,treat cause and effect ,bike world cover up chain to keep it cleaner with less maintenance or keep adding new (special expensive )oil to replace the oil washed off, yes that sounds about right,treat effect not cause , it used to be the same with helmets linings getting dirty ,take out and wash ,so cant take out linings so buy special expensive cleaners to clean the linings again treating the effects and not the cause problem although this seems to be getting better? as some helmets the lining is removable , there I have had my rant steve