FstBlkz28

iTrader: (13)

The way I understand it is that as long as the Crank dot is at 12 and the cam dot is at 6 you will be fine.

However This Thread sorta scared me.

But ... if the cam gear rotates twice for every one time the crank gear goes around. Then every time the crank is at 12 the cam gear will be at 6 ... correct?


Anyways, I thought i had the degreeing thing down, but after reading thru the thread above I sorta got alil scared. So can someone just clarify that my theory is correct.

TIA

racecar

The first post was way too long to read but the second one said it all.
Put it together with the crank at 12 and the cam at 6, line up the dots, perfect, you are done. Turn the crank one full turn and the cam will turn to 12, one more full turn on the crank and you will be back to where you started.
PS Take the spark plugs out to turn it. Don't turn the crank with the chain off and the rockers arms on.

eallanboggs

iTrader: (1)

A 4 stroke cycle has 4 strokes to make one power pulse. A 2 stroke cycle has only 2 strokes per power pulse. The reason 2 strokes rev so much quicker is because they make power every time they reach TDC, but 4 strokes have to come to TDC twice to make one power pulse. Your first statement is correct, but you have the second one reversed. The cam spins at 1/2 crank speed. To verify this just look at the crank and cam sprockets. The bigger sprocket (cam) spins slower than the smaller one(crank). Now count the theeth and you'll see the ratio for yourself. If your crank DOT is at 12 and the cam DOT is at 6 this time around, the next time the crank DOT comes back around to 12 the cam DOT will also be at 12. In order to complete the 4 stroke cycle the crank has to make to 2 full revolutions, but the cam only makes one. The crank is like your backbone because it carries the load, but the cam is the brains of the operation because he tells everyone else what to do.

777

iTrader: (21)

That post should scare everyone. INTO NOT USING STOCK SPRINGS WITH ANY CAM. There are hundreds of cam swaps done dot to dot. You have nothing to worry about. I am 99% sure that the reason he has problems (the post you listed) is because he used stock springs which hit coil bing, which broke rockers, and yea, you can see where that is going.

Byter

iTrader: (1)

It's true you SHOULD be ok if you line up dot 2 dot. What degreeing does do is tell you if the cam you installed:

1. Matches the cam card you received.

2. Matches what you think the cam specs are.

3. Confirms you are dot 2 dot.

There have been tales of the wrong cam being in the wrong box.

777

iTrader: (21)

You would think the company that sent the cam would then be responsible to give you a new engine. They will say you should've checked it, but in reality they should've checked it. I see no reason why it's not totally their fault.

FstBlkz28

iTrader: (13)

Yes I realized I had it reversed a few minutes after I left my computer last night ... i've been talkin cam/crank heads so much in the past few days i got tongue tied when I was writing this post.

thanks tho guys. i know that original thread boiled down to stock springs .... i just wanted to make sure that i still had the degreeing thing down correctly to save me more trouble.

Mr. Luos

iTrader: (9)

Maybe a stupid question...

But how do you make sure you are timed properly when you install a new motor with new chain? Both the crank and cam need to be at certain points in the cycle to be timing right, how do I know what those are when I put on the new timing chain?

777

iTrader: (21)

Piston #1 need to be at TDC and the crank sprocket needs to be put on to where it is facing exactly 12. Which isn't a problem if the crank is truly at TDC. It's keyed so you'd be off quite a bit if you didn't get it right. Then just put the cam in and line the sprockets up either 12 and 6 or 12 and 12. Preferably 12 and 6 because it is easier to see that it lines up. The cam has a dowel on it which fits into the cam sprocket so you can't get it wrong.

The way I did it though is turned motor so cam and crank are lined up 12 and 6. Then I took of the sprockets and put the new ones on.

Mr. Luos

iTrader: (9)

That is what I thought, but I wanted to make sure. Thanks!