well man you opened yourself up by asking why FI needs a fuel pump. that's fundamental operations of the system you're confused on so what did you expect?
i have been staring at this pic and can't see it either? one thought was a shim on top of the valve spring but how to move the rockers up & out of the way??? i don't see any thing near the cam lobes. do the rocker rollers come out and thus create room above the spring to get a shim in there? or do those 4 bolts (2 silver 2 grey) allow for the rockers to come out all together?
Looks like the rockers are on shafts and would be removed the same way as most other rockers, pull the shaft out the side after removing the retaining bolts. I don't get why there are 2 retaining bolts on each shaft though, instead of just 1? I'd bet this uses cupped shims over the tops of the valve stems. You wouldn't want those to bear on the valve springs themselves.
The head design looks similar to the current 530, etc. with shims over the vlaves shown as #25 in diagram.
Yes, just remove 22,23 and 24 then slide the shaft out AFTER measuring and calculating what size to replace with. The shims sit in a dish on top of the springs. It's really quite simple (the second time).
i seem to remember seeing a tool( somewhere on the web or maybe in my dreams )that depresses the valves, enough to remove the shim,when reshimmig the valves,looked pretty simple and saved having to dissassemble cams,but you must ensure motor@TDC
I think if you depressed the springs (and valves) at TDC enough to replace a shim, the valve would hit the piston. There is very little clearance there hence the dishes cut into the pistons so the piston doesn't smash into the valves. Perhaps this is doable at 180* of TDC but you will still have to be carefull with the little valve keepers not moving out of place. It really is quite easy to R&R the rocker shaft. With the valve cover off, I could change a shim in <10 min.
so those 4 top bolts out and the 2 cover caps (on the backside of the pic) and the rocker shafts pull out from the backside of what we see in the pic? rockers moved out the way & then replace with the proper calculated shim and reassy? actually that seems very simple compared to some of the OHV jap stuff.
Yes, if you're going to replace shims on both the intake & exhaust side. After you remove the two top bolts and the cap on the end, you can thread one of the 6mm valve cover bolts into the end of the rocker shaft a couple of threads so you can pull the shaft out. If you use a magnet stick it makes it real easy to r&r the shims. Don't forget to tighten the top bolts to the proper torque and remeasure the gap, it's that simple.
Okay, well what the hell is this 500exc all about? I'm confused. Euro only? That power plant looks like a kissing cousin to my 505's engine....with a kick starter.
Having the shims located on top of the bucket is nothing new. The early Z1 Kawasakis (73-80) had the shims located on top of the bucket and the camshaft rode against the shim. There is a tool that would hold the valve down so the shim could be replaced with one of the correct thickness.
Ever seen the disclamer on the bottom of the adds for illistration puposes only , All so if you zoom in the sticker on the rear fender has 350 , why pay a photographer $$$$ when you can use the same image , but who cares there the engine format correct this time no more twin oil gallaries,