Been playing with a unusual Cyuna motor which i got running to sell. Motor was one of 3 left over heading to the scrap after my mate passed away. Was partly dismantled with rusty rings & seized piston etc. Just cleaned it up & assemble then damn it no spark but as luck would have it i found earthing the yellow makes it run. Welded a flange on & bolted my old bucket racing 100/125 pipe on to sort of quieten it down--not much though. 215cc googling specs. Tons of Comp to pull over. Runs perfect.
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And another motor. Rotax 462cc twin. Had the head off & not sure why but maybe just to have a look. Spun over good so just bolted the head on using O rings that were in their groves just oiled them. Had no deep dome nuts so just rolled some small Orings down the studs & into slight recesses with nuts then short dome nuts but i'll find out soon enough if it leaks water & chances are. Facinating motor but had no spark so nearly stopped the plan before i goit going. Now this is stupid but i spent a day testing all wires & guessing mostly, had voltage spinning it with a big slow drill which kept me keen. Then i decided to look past the pull start pullery into the flywheel & @##$ its got points haha--two of them. I scratch them & bingo, spark but mostly on one. I'm not out of the woods yet but got it started on one cylinder & am hopeful of two in the end. So much Compression my big drill spun out of my hands & lucky not to break a wrist. Have the radiators so will see what happens. Motor has a little oil bottle & it pipes the oil to a central drive which spins the rotary valve & i think in turn it runs a water pump--i hope. Oil is circulated back to the little tank. Apparently--googling--this is the sedate version but go fast one has twin carbs & other stuff. Anyway--what we do for fun. Had an aircooled one too but that's gone & didnt get to run it.
youtube.com/shorts/_sUTSsnTuzA