if you could point me to an example that would be helpful. At this point I'll try anything.
---------- Post added at 12:42 PM ---------- Previous post was at 12:35 PM ----------
so how do you keep the driven on the shaft in this scenario? and how do you manage the distance between the driven and the drive?
What did you think of the idea i had where I put the sprocket under the engine?
Well, that shaft needs to be replaced (and at least one bearing is missing) it's only to show you the kind of jackshaft and it's _rough_ placement.
it's a plate that directly fits the four engine bolts,
and is secured with the very same bolts to the engine mounting plate
And since the js-plate isn't slotted the center to center distance is fixed chain tension will be achieved like with a a cent clutch by moving the engine back and forth along it's slots
(In that case moved in unison with the JS)
The jackshaft itself is then just an ordinary jackshaft
whatever kind you want (threaded or drilled and tapped or even with a slotted end for a snapring if you so desire)
And the driven is afixed by such means (a nut, a bolt or a snapring)
whichever JS you pick.
You can put the Sprocket where ever you need it to be (within reasonable ranges of course),
but if you want it just below the engine, you will need a different jackshaft setup
two pillow blocks left and right and the TC sprocket in between like so:
And for that you need structural support for the pillow blocks,
that's why I suggested the plate that bolts to the underside of the engine first
Also keep in mind that you need the clearance for a large enough sprocket too..
which looks to be unlikely with the current engine mount *shrugs*
Oh and see.. that setup uses locking collars to keep everything in place, another option I forgot to mention above
In that scenario you run into tension looparounds, but it's still a viable option.
first you tension the chain by moving the jackshaft pillowblocks in their slots,
then you tension the belt by moving the engine.
(and if you cannot achieve good tension, you add/remove a link and start over)
Now chain.. yes 530 chain is way stronger than #40..
But 420 chain is way stronger than #40 and of the exact same outer dimensions as #41 (so it fits all #41 sprockets)
you can safely run your kart with #40 chain,
and certainly run it with 420 chain having quite a security margin left.
The reason I'm for half inch pitched chain (#40 or 420)
instead of 5/8" pitched (530)
is nothing but the thread pitch..
you want a fairly large toothcount on the rear axle, and the bigger the pitch, the larger the diameter of the needed sprocket will be of course (25% bigger to be precise)
And that will cause significantly reduced ground clearance.
OH and sure, you could get a smaller toothcount on the TC sprocket,
but that comes at a price (additional chain and sprocket wear)
Since the power is only transmitted through the engaged teeth on the TC sprocket
and spreading all loads over 5 or 6 teeth is much better
than spreading it over just 3 or 4
(again we talk ~25% quicker sprocket wear)
So IMHO the more teeth the better, even if they're a bit smaller in the end.
'sid
