Predator 212 cam/rod knock?

[408mini]

Having trouble with this predator 212 I “built”

it has a billet rod, stock cam, 22lb springs, ported and polished head, aluminum 1/4 pushrods and a 28mm chikuni carb.

It’s always had problems with shearing keys and I ordered a new crank because the last time it sheared the key it damaged the crank pretty bad.

I just took it apart today to investigate the knocking and it sounds/feels like it’s coming from the cam instead of the rod.

Any tips or ideas where it could be coming from is appreciated.
Video <— video of the “knock”

 

[Charles S]

https://oldminibikes.com/forum/index.php?forums/honda-clone-predator.36/

 

[sparkwizard]

I assume it still knocks with the side cover installed. What I am seeing is cam movement because the cover is not installed.

 

[Studeman68]

Even flat heads sound like that when the cover is off. Put it together (properly) and run it.

 

[408mini]

Follow up post, everything is back together and torqued down but still a audible clicking noise from the engine

Video 2

 

[SAS289]

What you are doing there got me curious. So I put my 224 on the bench and removed the spark plug and blower housing. And as expected I can get the same knocking that you have.

My built 224 is not off the bike because there's an issue. It's off the bike because I'm playing with a Chikuni carb on a stock 196.

I would say that you should finish assembly and run the engine.

 

[Minimichael]

Follow up post, everything is back together and torqued down but still a audible clicking noise from the engine

Video 2

Is it the same clicking as in the vid? And when the motor is running it's a continuous clicking? Or intermittent?

 

[408mini]

Is it the same clicking as in the vid? And when the motor is running it's a continuous clicking? Or intermittent?

Just got the engine running, carb isn’t tuned or jetted yet but the clicking is harder to hear while it runs.

its the first time for me hearing it run with a pulse pump so the sounds are hard to make out.

Video 3

 

[Minimichael]

Just got the engine running, carb isn’t tuned or jetted yet but the clicking is harder to hear while it runs.

its the first time for me hearing it run with a pulse pump so the sounds are hard to make out.

Video 3

Pulse pump ain't got nothin to do with it. I thought you took it apart because of the clicking?

 

[BrownStainRacing]

https://www.eccarburetors.com/clearance-wildcat-predator-58mm-crankshaft

 

[sparkwizard]

https://www.eccarburetors.com/clearance-wildcat-predator-58mm-crankshaft

I'm glad you came along. I forgot where I read that. Thank you.

 

[SAS289]

Except that his engine is a 212. Looks like a non hemi block.

 

[BrownStainRacing]

Except that his engine is a 212. Looks like a non hemi block.

Lol, nice catch.

I musta got lost with your 224.

 

[mchadsey1]

Have you drained the oil since you have had it running ? Any metallic particles?

 

[408mini]

Have you drained the oil since you have had it running ? Any metallic particles?

just did an oil change before I took it apart, average amount of metal that you see in these engines, no huge chunks in the oil

 

[Minimichael]

Is the click occurring at a particular point in the 4 stroke cycle?

 

[sparkwizard]

Did it click before you installed the billet rod?
Did you check clearance when you installed the rod?
Was rod to crank clearance in spec?

 

[creia]

What sparkwizard said^^^^
You should be using a product called "Plastigage" for this purpose (very important!). Google it if you are not familiar with it.
Michael

 

[sparkwizard]

My next question concerns a torque wrench.
Do you own and use a torque wrench? I ask this because you have been shearing flywheel keys to the point you need a new crankshaft.
If EVERYTHING is not torqued to spec on an engine used for high performance, it will shake and rattle itself to bits.

 

[sparkwizard]

I just watched video #2. Turning the engine by hand, that sounds like rod knock. Remove the plug and see if the noise is still there when turning the flywheel by hand.
How much clearance do you have between piston and head? How thick is head gasket?