Tzed250
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Here we go...
Building a SP125C / 101B Kart Saw
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That sense not make my mother says my saws cold in garage not run at all.
ausneil 1
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Originally Posted by adam345
the centrifugal force produced by the inertia of the flywheel is strong enough it would be best lighten the wheel and cut a piece of lighten flywheel fins would have less weight which can go faster and with less inner strength she explained centrifuged my father from certain rpm it produces many internal forces in the motor and just destroying everything.
Originally Posted by Tzed250
Here is a single with perfect primary balance. Ducati Supermono engine. Notice the second rod 90° from the main rod and piston. The balance rod is toggled to a rocker which dummies a second piston. This engine revved to over 10,000 RPM which is quite high for a 500cc single. The engine had a slight secondary imbalance. A rocking couple induced because the rods sat side-by-side on a common crankpin.
the centrifugal force produced by the inertia of the flywheel is strong enough it would be best lighten the wheel and cut a piece of lighten flywheel fins would have less weight which can go faster and with less inner strength she explained centrifuged my father from certain rpm it produces many internal forces in the motor and just destroying everything.
Originally Posted by Tzed250
Here is a single with perfect primary balance. Ducati Supermono engine. Notice the second rod 90° from the main rod and piston. The balance rod is toggled to a rocker which dummies a second piston. This engine revved to over 10,000 RPM which is quite high for a 500cc single. The engine had a slight secondary imbalance. A rocking couple induced because the rods sat side-by-side on a common crankpin.
Tzed250
Addicted to ArboristSite
Lord love a duck....have I actually been drug into this????
ozflea
Good ol' BP Zoom 25-1
Lets just stay on track forget the rabbiting on and get the engine going those bolts for the rod are the wrong ones you need the splined bolts sorry unless you want a rattler instead of an engine
Torque for the splined bolts is 110 in pds as far as the seals go as per the pic their back to back.
McBob.
Torque for the splined bolts is 110 in pds as far as the seals go as per the pic their back to back.
McBob.
ausneil 1
Addicted to ArboristSite
Mr. McBob, I have to disagree on the seals. I have had many, and i mean many
big inch Mac's appart, Weather it be an 890, 895, 740, 790, 795, 797, or SP125,
I have never seen the flywheel side seals back to back. Not even once. I have had
a few that had never been appart.
Lee
ozflea
Good ol' BP Zoom 25-1
Sorry Lee but what Mac says is right in my books what you do is your doing not mine, sorry to disagree.
McBob.
McBob.
All my IPL's (karts and 125s) show the seals back to back. My one and only dismantled 101B has them both with lips inward. If it weren't for the weep hole I would had bet the MAC draftsman just made a mistake - but with the weep hole the outer seal really should have no pressure or vacuum to deal with so I don't see why it would make any difference how the outer seal is placed - but since I don't know I am going to follow the IPL and replace mine back to back. Ron
I have had a decent number of 125's apart as well, and have found all my seals installed with the lips inward (toward the crankcase) as Lee stated. Here are some disassembly photo's of one of my SP125's which appeared to have been unmolested from factory.
Regards,
Chris.
Regards,
Chris.
I've been through about 17 of the 125 motors and every seal was installed the way Lee is referring to.
Pes+ told me about a cool trick though, installing the inner flywheel side seal with the lip facing outward.
He said the seal would last longer that way. I haven't tried it yet but have been tempted to.
Several of the saws I've taken apart were converted to solid state ignitions and did not have
the second "dust cover" seal and they ran fine without it.
Pes+ told me about a cool trick though, installing the inner flywheel side seal with the lip facing outward.
He said the seal would last longer that way. I haven't tried it yet but have been tempted to.
Several of the saws I've taken apart were converted to solid state ignitions and did not have
the second "dust cover" seal and they ran fine without it.
ozflea
Good ol' BP Zoom 25-1
Since we all have different ideas and since the saws have been around a very long time do, as you see fit .... me i'll stick to what i was taught by McCulloch unless you's know better.
McBob.
McBob.
So are you saying Terry Ives sold me the wrong bolts? AFAIK, he's the best Mac builder out there.
ozflea
Good ol' BP Zoom 25-1
There's a few good Mac builders around and Terry is one of them Mac used splined head bolts and with them cured the clearance problems
you encounted in all the years i ran Mac's i think i had one failure put down to bolts but that was my fault for over revving the engine.
This brings to light the weakness in the 125's no compression control the 101 you can up the compression to slow the piston but in a 125
you can't so you must watch the revs and limit them.
McBob.
Brad- it's pretty safe to say that you can take Terry's advice to the bank. He's built more championship kart engines than every single person on this forum combined. If Terry says it's good, then in Terry I trust.
ozflea
Good ol' BP Zoom 25-1
I agree Terry's advice is fine and you can use those bolts the reason that they are stronger in yield strength than the Mac bolts but expensive compared
to the Mac splined bolts .......... you can use what you want but i'll stick with the Mac splined stuff and they dont have to be modded.
Some use the bolts Dave Bonbright suggest's from the US820 stronger again i have them here for my US820 Copperhead not needed really unless
you push the engine of any mac over the top.
Some of those bolts need modding with they are seated area too before use or will cause the cap to fail.
McBob.
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ozflea
Good ol' BP Zoom 25-1
Here's the thin seals for the 101, 125 and PM 105, 125, There fitted back to back
The O'ring between the side plate and the crankcase replaces the gasket make sure you use a snug fitting O'ring.
McBob.
The O'ring between the side plate and the crankcase replaces the gasket make sure you use a snug fitting O'ring.
McBob.
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cpr
Addicted to ArboristSite
Funny about that side cover gasket. It's a dead-nuts fit as a head gasket.
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Here's the thin seals for the 101, 125 and PM 105, 125, There fitted back to back
The O'ring between the side plate and the crankcase replaces the gasket make sure you use a snug fitting O'ring.
McBob.
You can't use an "O" ring where the #62 gasket is on any 123cc Mac
do to the cut out in the block. All of the 123cc Mac's i have had appart
were sealed with some type of sealing compound. You can use a gasket
but i haven't seen a gasket yet in all the 123cc Mac's yet. Funny how the
101 IPL shows a gasket but the 797, CP125, SP125 show nothing.
I will continue to install the seals the way i have always seen them.
Lee
