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Flywheel Install

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Shamelessbullet

New member
So I think I'm going to install my Billet flywheel this weekend. I know there's all the fancy stuff where u buy a timing light and a degree wheel and I'm really not looking to be super technical on this. I've read that stuff isn't really necessary. So here's my game plan so far. I've watched some tutorials and so far I've concluded this:
1. take old flywheel off and key
2. lap the new flywheel (its not necessary to take out the whole crank is it?)
3. CLEAN IT
4. Put the old key back in (make sure its parallel to the actual crank itself)
(not planning to add a aftermarket key because the billet flywheel is already advanced by 8)
5. Put the new flywheel on
6. make sure the magnet is spaced the recommended distance away from the flywheel, which is in the instructions.
7. Torque the flywheel nut. Now this is where I have some questions.
when torqueing the flywheel on, I know you have to have it stay in place while being torqued. But how do I know when the flywheel is in the position it needs to be in when I'm torqueing it? do I match the magnet on the flywheel up with the magneto that sparks the spark plug? do I just eye ball this? Please correct me if I'm wrong on anything.
Also, does anyone have any tips on keeping the flywheel still while torqueing it?
 
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I don't understand all the timing stuff quite yet. So all I have to do is line up the magneto with the magnets on the flywheel. does my flywheel have those lines marked on it like his does or did he make those marks? Also, do I get to get one of those timing wheels.
 
If using a stock cast flywheel, line up the magnet directly under the coil. That will be the firing point for that flywheel. The one in the video is a Billet flywheel and it comes with those markings. I got that one from Comp Cams.
 
OK so I found out if I have the key I don't need to really find a specific position for it. The stock timing is 25-26 on the predator 212cc and if I have a flywheel with advanced timing built in by 8 and I use the stock key I should be at 33-34. So I just turn my flywheel all the way and itll stop and then that will be 33-34 degrees ?? then I can torque it ?
 
Might want to also check your cam and see what recommended timing you'll need....usually when you order a different cam it'll come with a little card that has all the information about the cam including timing. Billet flywheels usually meet the required timing advancement for most of the popular cams while using a stock key if that's what you want to do.
 
well I have a stock cam. When I decide to upgrade the cam ill look into it and get a timing key if needed. and I think I was completely wrong about turning the flywheel until it stops. if I put the key in and put the flywheel in its automatically at 34-35 no matter how I spin it, correct? just wanna make sure I'm doing this right. This is my first small engine build.
 
Shamelessbullet said:
well I have a stock cam. When I decide to upgrade the cam ill look into it and get a timing key if needed. and I think I was completely wrong about turning the flywheel until it stops. if I put the key in and put the flywheel in its automatically at 34-35 no matter how I spin it, correct? just wanna make sure I'm doing this right. This is my first small engine build.
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In my honest opinion, and this is just out of the small info you've supplied. If you're going to invest in a billet flywheel, I'd be careful with your use of it. If you're looking to turn more rpm's and have the governor removed...you'll need to then get a billet rod otherwise the stock cast rod will come apart at higher rpms. If you're sticking with the governor, I honestly wouldn't invest in one of the more expensive "bolt on" parts.
Get the billet rod and flywheel with the governor removed and you'll be able to turn as fast as you want....until your valve springs can't handle it and basically act like a "rev-limiter".
If you're not looking to race but are "intrigued" with the idea of building your own motor for play....absolutely go for it and dive right in! But AT LEAST get a billet rod and a billet flywheel if you're wanting to build this up.
If you want to stay stock...I wouldn't invest in just a billet flywheel. It won't do you the justice of what it's intended for.
Just my 2 cents on this
 
I think you have the wrong idea of what I'm trying to accomplish here. I'm building this small engine to 10-15 hp. I've got the billet flywheel in my hands. Then after I get this installed I'll be doing rod. Then after rod it'll be springs and cam etc etc. I just need some advice on installing the flywheel for now. I just don't want to tackle upgrading everything at one time for my first build
 
Shamelessbullet said:
I think you have the wrong idea of what I'm trying to accomplish here. I'm building this small engine to 10-15 hp. I've got the billet flywheel in my hands. Then after I get this installed I'll be doing rod. Then after rod it'll be springs and cam etc etc. I just need some advice on installing the flywheel for now. I just don't want to tackle upgrading everything at one time for my first build
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Ahhhhhhh ok then that makes it better. If you're doing that, and don't have all the specialized tools such as a timing gun and such, then your stock key should be fine. The billet flywheel has been adjusted for the correct timing....I'm saying this because I assume you're getting a different cam eventually. The timing might not be absolutely perfect but I don't believe it'll be far off enough to notice a difference. You can take it to a shop to get it exactly dialed in, but you should be alright if not.
 
Ah ok gotcha, so as far as throwing it on I won't have to do anything special? Just put the key in put the flywheel on and torque it on ? After lapping it obviously
 
I don't know ur skill level. But here is that "simple" way to do a flywheel... step 1 get a long rope that fits in the plug hole (about 5-6 foot long) step 2 pull valve cover and undo the rocker arms ( moving the arms off the push rods) step 3 feed the rope into the plug hole tell you know the motor won't roll over (do not loose the rope in the cylinder!) Step 4 undo the fly wheel nut (pull the starter cup and fan off put nut back on the crank spin it 3/4 of the way down.) Step 5 use a pry bar and wedge it behind the fly wheel loosely. Step 6 use a hammer or small mallet to hit the crank nut. (As u hit the nut pull the pry bar to you if it doesn't pop right off pick another spot 1/4 -1/3 around and do it agen) step 7 slip new fly wheel on lining up the key way ( make sure ur free from the coil. And no need to lap with the oem key) step 8 spin motor over replace fan and starter cup. (Make sure the hole lines up with the nipple on the starter cup) step 9 torque flywheel nut to 54 foot pounds. Step 10 spin motor over and pull rope out. Step 11 use a biz card fold in 1/2. Undo coil bolts. Step 12 slip biz card under coil and spin motor over tell the magnet sucks the coil down. (With the biz card fully under the coil legs. Both sides.) Tighten coil step 13 re set rockers and valve lash.
 
^^ Right there....step by step exactly how I would do it as well. Good luck and any other questions just ask
 
I installed my billet flywheel last night, but I have a couple more questions. as far as replacing the fan and starter cup. what do u mean? do I need an aftermarket flywheel cup? the holes do not match up however I did make sure the nipple matched up on the flywheel and the cup. But again the holes do not match up. I torqued it to 65 ft lbs cus honestly 55 didn't seem like enough...... I held the flywheel with 1 hand and torqued It with the other, which didn't seem super tight to me. but then again Ive never used a torque wrench before.
 
well I ment I used a part of a torque converter the part with a plate and key in it and held it on the crank (clutch side) with one hand and torqued the flywheel nut with the other. why does it matter if I held it with my hand? as long as the bolt is torqued down it should be fine right? cus the timing is already set with the key I thought.
 
Shamelessbullet said:
well I ment I used a part of a torque converter the part with a plate and key in it and held it on the crank (clutch side) with one hand and torqued the flywheel nut with the other. why does it matter if I held it with my hand? as long as the bolt is torqued down it should be fine right? cus the timing is already set with the key I thought.
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Make sure you're using the correct torque wrench.....Ft/Lbs vs. In/Lbs (foot pounds vs. inch pounds)
 
Shamelessbullet said:
well I ment I used a part of a torque converter the part with a plate and key in it and held it on the crank (clutch side) with one hand and torqued the flywheel nut with the other. why does it matter if I held it with my hand? as long as the bolt is torqued down it should be fine right? cus the timing is already set with the key I thought.
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I don't see 65ft/lb of torque held by one hand, you need to do it properly or you will be the owner of expensive chunk of Aluminum.
 
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