mm-hmm coffee we're back in the shop if you're just joining us for the first time welcome
to a pretty friendly shop here there's me paul brodie mitch behind the camera good job as usual
we're working on the tiger cub here and this is going to be a bit of a challenge
because it's kind of a complex thing i've got a ignition system here which i purchased i bought
all the cub stuff i i looked it up this morning on the 6th of june last year in in 2021 i purchased a
bunch of cub stuff a couple months into the project someone told me that oh you need a
ignition system you should buy a electrics so that's what i i got electrics with an x on the
end and so i thought okay this is great and then i realized that how this mounts
here's the here's the primary chain case and this mounts inside can you see here all the studs you
take out this one you add that one it mounts onto the studs there so what happens is when you pull
off the case unless you you drill a hole through here and you poke the wire out it's hard to take
off the case because this wire goes into here another problem with this is that you can't uh
check the timing of the ignition because you can't put on a degree wheel this is what i like
to use and this will mount somewhere like that you have a pointer you you start up the motor
you have a timing light and you check where the spark is so with this system here you just have
to guess so i didn't like that so what i wanted to do was to mount this
on here this is the rotor this is the stator so that's going to get mounted like that
and it wasn't long after i got this that i found out about
this system here it's available in the uk off a company called feet off i think strange name
so they have a system here and it's got a a pvl unit so after i found out that i thought ah
well i i've got this this is a nice a nice unit so i wrote to them i sent them an email i asked them
if they would sell me this piece of aluminum here which is cnc machine i didn't even get an answer
so what i want to show you is is the bolts these are the bolts that hold hold the crank case it
holds this half onto this hub can you see how it goes down like that well when you have a system
like this can you see how it's raised up you need a longer bolt so i wrote to these people i said
i'm interested in those bolts would you sell me those bolts allen screws and they said no
so then i said well okay then that's fine would you tell me where i can buy them and they said
no so i thought oh gosh so i searched the internet and i had other people looking as
well these bolts are really hard to find it's an odd odd thread pitch of 22 threads per inch so
i could not find the allen screws so if you don't have the allen screws you can't hold it down so
this is here's my solution let me show you this i bought an eight millimeter allen screw that's
too long this is stage one i center drilled it i'm i machined it down there's the nut the nuts gone
and so the nut goes over top and then i put it in the lathe and i machine my longer allen screw
so i think that's the first set we're going to do today i did this one yesterday as a test so we're
going to go over to the lathe and we're going to do some machining right off the bat and then
we've got a big chunk of aluminum a 40 piece of aluminum that's how much this cost me
i don't have a drawing but look i got cardboard cutouts i've got notes i've got all sorts of stuff
so i think it's gonna work and i also have other notes as well so no drawing but sketches and notes
let's go to the mill no the lathe let's go to lathe and
do some machining we're going to cut some threads
okay we're getting close to the thread depth now what i have to check now is the od because as you
cut this it raises up the surface and when i was doing it last night i found that this was
oversized as compared to the regular bolt so we have to do a little bit of filing now okay this
is what i want to show you here's the thread this is the standard bolt and it's at 306 and this here
see it's at 310 they're probably more up there three 312. i have to file that down to get this
i have to get the same od as this bolt here
we're on 306
306. okay so same size so now we got a little bit more to take off
and then we'll we'll see how the nut fits
okay so the nut goes on and last night when i was doing this i got the nut on
there and i thought great so i i want you to see this it doesn't have any slop
there's very little slop it goes on but there's no slop so when i when i grab this
and i put it on here can you see how it spins on can you see can you see this slop
there that's what i want because i made this one yesterday and the nut went on it
but it wouldn't fit in the case because i didn't have enough of a thread depth
so i learned last night and that was a lot of work to make this one fit i had a diamond file
a a triangular diamond file and i'm on the lathe and i'm filing down the thread to make
it fit into the crank case so i can't say it was smooth sailing so we're going to take off
a little bit more because we need that slop just a little bit of slop to make it fit
that took a pretty healthy cut yeah okay you can see that move can't you
we're going to cut that off we're going to see if it fits in the case because we got so
much more to do today half an hour to make one thread on an allen screw how long can it take
it's a hard piece of metal
so here's the new bolt we're going to put on some anti-seize here
because we don't want it galling or anything like that let's see how it fits this is first first try
look at that that one goes in a little easier than the first one that's okay beautiful
so now i can show you a few things on on the engine here so what's going to happen is
this is is going to get machined and it it locates into this hole and this hole here
these bolts get hidden under the under the sprocket so you don't see those ones
but these two are what holds on the plate and there's also
a third mount that goes here this is cad design it's cardboard aided design
so if i take my screws here like this i spent a few hours doing this figuring it out
and so the tensioner has to go in here for the chain so i'm going to
make a tensioner out of delrin you can see there and that's the shape of it
see i've got a hole there that's where the pivot is i want to show you a couple things i like the
concept of this but on on the tensioner it's only held on one side and i don't like that because
you've got i mean this is a very very strong motor it's probably got 16 horsepower and i don't want
the tensioner to be held just on one side i also want you to notice that it's fairly flat
my tensioner i know like if i hold it at the same angle can you see how this one here has
a lot more curve to it on the crankshaft it goes anti-clockwise looking from this side
so i think that how the chain fits it does it wants to do a nice arc
so that's what i've got here i've got the pivot down there can you see that little circle there
and so that fits like that what happens on this one here it wants the chain to go like so
because it's flat right it's flat and then it ends i don't think that's natural for the chain
i think the chain wants to naturally arc if you look at photos of a race bike for example
as the bikes under acceleration on the lower part of the chain it always arcs up as much as it can
so my design here's the two pieces and uh and and the tensioner is gonna go in between so i
i came up with this design because there's not a lot of room for nuts or anything like
that so you can see how the shaft has a little shoulder here and it fits into the bottom plate
on the top plate it sits a little proud and there's a plate with two allen screws there
that holds that shaft down so that's what i'm gonna make and that's going to
be made out of this plate right here i've got those two holes marked so
i think it's time to go to the mill
milling time
we're going to the bandsaw now we're going to we're going to cut out a shape here
so i don't have to mill as much
okay while the mills like it is i think we're going to drill a big
hole right there that's going to let the let the crankshaft come through
there we go this mounting system for the ignition system it gets held one spot here
and two spots here and there's a third spot here it gets held right here if you look at the
drawing here that is the third spot and you see there's a bolt or an allen screw that goes through
that's the allen screw right there why i'm showing you this is because this is a casting
and to get the casting out of the mold you need a draft angle usually of of two degrees
can you see how this is is not perpendicular that's basically perpendicular that there
is a draft angle there so what they've done on this system here
can you see how this is angled a little bit and there's a radius right there because the radius
has to fit right here see that corner there that's where it goes so what you have is a flat surface
you have a flat surface and you have a round surface and you're asking those to mate
nicely so i've got the engine all apart so what i'm going to do is i'm going to set this
up in the mill now i'm going to use a 5 8 end mill and it's going to come right down there
and face a little bit on the bottom it's going to go in a little bit as well and then we're going
to take a rod and that rod is going to be held in there so this is going to be way more secure and
then it's going to get center drilled in the lathe and then when i put on this piece here i dial up
to the center drill or i just put a center drill in there and then i drill the hole through the
plate everything's perfectly in line that's the plan so right now what we're going to do is is
to take this apart we'll just have this left-hand crank case and we're going to mill down next job
on the mill so with we're slowly working through all these little areas that have to be attended to
can't think of anything else i'd rather be doing
there we go that's all we need i can't take too much
because i'm getting too close to this surface here so i have to be careful
that's what it looks like see i've got a nice little 5 8
5 8 cut 5 16 radius now we just need a piece of aluminum to go in there
if i get a drill the right size
and i made a felt pen mark on this
that's one way of maybe not totally accurate but let's let's try it
you hold that in like that
is this an approved method what do you think mitch
or is it reeking of mickey mouse hopefully not so there we go there's a there's a mark i think
i can get the center out of that so we're gonna center drill we're going to drill a
quarter inch hole and then we're going to countersink and then we'll see if it fits
oh look at that that's a nice that's a good fit that fits quite nicely
i'm going to glue that in as well i think so
anyway it could be a little longer
so that that's some that's in progress we have to drill a hole in the lathe now we'll do that after
it's been great having you in our shop here thanks for coming along i hope you enjoyed watching this
it's a bit of a project i took on here we'll see you next time you take care stay safe
i wanted to show you something it's the flywheel i was going to use
and i had this other other flywheel in there just for
you know just to hold things in place what i want to show you is this
can you see that is that worn out can you see how much movement there is look you can even
see the heat stains there how it got so hot i can't imagine how much noise this engine was
making and then i was looking at it can you see here they hammered so hard can you see
there's a crack going right from the crank pin right up to the edge of the flywheel so
these little cubs sometimes they got really abused like seriously abused i feel sorry for them