Okay all, after a thirst quenching drink or two, I got back to the tools, I started to work on a new 50cc motor when this thread commenced, In doing so I machined the crank & balanced, its that friggin precise a ballerina could do all her flang dangled moves on it, without being hindered in any way, Its basically a two piece crank with roller bearing to conrod big end.
I machined up a few crank sets, and every one of them was different to the one before, but then again when balancing anything, if your serious about clearances & tolerances, its got to be done on an individual basis, I have built many small block engines in my life & never have I come across two blocks which needed identical modifications in balancing, or for that matter never seen two castings for block, crank and cylinder head which were identical to a tee, there all around the mark
I also de burred all sharp edges & injection dags from manufacturing to all the external faces of the block, commenced internal porting to the crank case, I still have to finish but before I want to go any further I need to build a mounting plate so I can flow test these motors on my SupaFlow bench, (not as quick and easy as one might think though) as I need to see when & at what stage I start to go backwards or waste my time thinking Im going to make an improvement when actually wasting electricity & shooting myself in the foot, I will work on the locating dowels for crank case & cylinder head and should have it suss by next week.
As for the cylinder head, I will create my own, I will keep you all informed as I move along, as I will start from the bottom & work my way up
But I must state its not about going all out to create a motor for the extreme sports category, I agree totally as Jim has stated, its about creating a honest, reliable & value for money starting point, from there someone can take it to what ever heights they like, I want to create a solid bottom end to start with.
A couple of pics of what I have done so far.
Cheers all.