Recently the subject of "cheap" vintage two strokes came up.
i decided to post this so people who want to do vintage karts on a dime have a chance.
parts of the text i swiped from emails and earlier posts sorry for any repitition.
on two strokes easiest and cheapest is a mcculloch saw motor.
the saw parts strip off easily and if you hunt around they still can be bought for forty bucks or less.
i've bought some for 10 or 20 $ at swap meets and flea markets.
you end up with a complete motor less manifold motor mount and clutch.
these motors all have a great parts interchange and things like points and gaskets are commonly available.
i have about ten saw motors with several different specs that all are good for kart motors.
all bought for less than 100$
below is a mc250 tapered shaft complete saw and a mc450 tapered shaft converted saw to kart motor.
the parts in front are most of whats removed.
as you can see its pretty simple.
sorry about the double post but can't do more than one picture.
anyone with basic mechanical skills can remove the excess parts.
most of the saw motors are in better shape than the kart motors too.
something to do with being run within their designed limits i suppose!!!part two
below are just some of the mcculloch motors that'll work with a kart clutch.
i also included the cc and cu (thanx for the reference mcbob!!!)
300 80cc or 4.9 cu/in...
380.. 87cc or 5.3 cu/in..
380a ..87cc or 5.3 cu/in ..
440. ..87cc or 5.3 cu/in ....
450.. ...87cc or 5.3 cu/in...
550... ....99cc or 6.03 cu/in....
Super 550.. .....103cc or 6.3 cu/in...
640... .....80cc or 4.9 cu/in..
740.. .....99cc or 6.04 cu/in..
790.... .....103cc or 6.3 cu/in...
795.. ..103cc or 6.3 cu/in...
797..... ....123cc or 7.5 cu/in..
Super 797.... ...123cc or 7.5 cu/in .
840..... ......99cc or 6.04 cu/in..
890... .....103cc or 6.3 cu/in..
895... ....103cc or 6.3 cu/in..
here is a view of the converted motor with a stock kart manifold they go for about 10-15$ dollar on ebay.
the carb you get from the saw
the chain cover is from azusa and the dry clutch i had but you buy them new or if you're good with lathes and welding just change out the sprocket on the saw bell.
the saw clutch will work for a while at least .
or i can sell you a nice oil hartman clutch.
the motor mount is available as a repop steel about 45 cast aluminum about 55
my total cost on this one was about 200$
of course i started with a running saw.
mc200 and mc250's are really common.
you have to be careful with those as some have a tapered crank some don't .
go to mcbobs site for some info on that.
this is how to i.d. most of the older saws
go here: http://www.macbobaust.com/id.html
also BUY his cd with the mcculloch ipls on it well worth the money and priceless for parts interchange.
All of the mc saws i listed fit the standard kart clutch.
many of the saws are virtually identical.
the one big difference is if it's a mc91 style or mc101 style.
the 101's have a shorter crankshaft but are identical as far as clutch needs go.
yes stay away from 3200's
anything mac or not a number i listed probably won't work.
there are others listed on mcbobs site if you want to look.
you want a tapered crank so check the key in the upper right hand side of the stroke and bore chart.
as far as smaller engines don't worry about that just press the gas less.
for your nephews install a throotle limiter stop.
anything that prevents the throotle from opening fully.
run the saw carb to as you won't get maximun performance rom the little carb.
that's true but for what you get it's a great bang for buck ratio.
and the internals of the motor are rare as beat up as a kart motor.
usually the worst repairs is replacing seals gaskets and sometime the rings.
also fedco is able to remove the head and set up properly spaced threads so you can add a removable head .
with that service being offered the mccullochs are likely to continue dominating the vintage kart scene since there were millions of these saw made.