Predator 212 Upgraded and No Start

[NegativePanda]

Hi All,

I've run out of ideas and instead of stalking the forums I'm actually needing help. I've tried everything I could find in regards to my issue.

I started my first predator 212 non-hemi modifications and I can not get this guy to start. Just in case I do live at 6,000. When I first got it put back together a few months ago after a ton of pulling it ended up starting up. It would take lot of consistent pulls to get that.

Here's everything I've done to the engine:

• Mod2 Cam
• 18lb springs
• ARC 6254 Billet Rod
• Flat-Top Piston (70mm, .570 Compression Height)
• Nibbi PE22 Carb - I've even returned and got a new one.
• Arc 6695 Billet Flywheel

Here's everything I've tried to get it running:

• Set valve lash at .003 at TDC, verify lash after pulls, reset lash multiple times
• Try different/New Gas.
• Verified Mod2 cam time is set correctly
• Verified, tested and use couple of different spark plugs - Spark is fine and lash of starter is .030
• Using stock timer key as directed by Arc Billet Flywheel for the built in timing. Verified key is not sheared.
• Messed with carb settings, taken carb apart cleaned and verify things were working as expected. Replaced carb from 26mm to 22mm. Both Nibbi
• Tried engine starter with first carb
• Tried Drill start

I'm not sure what else to look for and check. I was thinking I had incorrect Billet Rod and Piston but GoPowerSports confirmed the two would work together. Did I overlook some timing. Any help or tips or even a direction I could research into is greatly appreciated.

 

[Charles S]

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

 

[Minimichael]

Try a non-ninbi carb? Or, lots of consistent pulls makes me think timing is off maybe

 

[NegativePanda]

Try a non-ninbi carb? Or, lots of consistent pulls makes me think timing is off maybe

Yeah I think I'll get a Mikuni and try that.

 

[creia]

Did it EVER start and run? That is to say, BEFORE you did your "modifications" to it?
Michael

 

[NegativePanda]

Did it EVER start and run? That is to say, BEFORE you did your "modifications" to it?
Michael

I wouldn't know I didn't think about testing it as I basically was going to just use the casing and stock arm.

 

[Minimichael]

Yeah I think I'll get a Mikuni and try that.

I was gonna suggest the stock carb.

 

[sparkwizard]

What is your cranking (pulling) compression?
Big cams bleed off low RPM cylinder pressure.
After pulling multiple times, is your plug wet, is it dry, is it wet and black, is it oily, does it still fire?
Stock carb is always my choice.

 

[NegativePanda]

What is your cranking (pulling) compression?
Big cams bleed off low RPM cylinder pressure.
After pulling multiple times, is your plug wet, is it dry, is it wet and black, is it oily, does it still fire?
Stock carb is always my choice.

Thanks for this. I went and got a compression test kit and found out my pulling compression is 0. From what I’ve seen before it should be 60 correct?

 

[sparkwizard]

Without knowing your cam specs or your head/ combustion chamber specs, I can only say 60 is always better than 0.
I can also say that at 0 PSI, it will be nearly impossible to start.

 

[Minimichael]

Maybe valve lash then, or did you forget to install the rings?

 

[sparkwizard]

You also made no mention of a head gasket.
I would start there.

 

[Minimichael]

Did u replace head bolts? Maybe they're bottomed out?

 

[NegativePanda]

You also made no mention of a head gasket.
I would start there.

After running that compression test I did a leak down test and could hear air leaking from the gasket. I thought it was gasket and pulled the head back a bit to peak and from the same area I heard the air I found these chips in the header at the edge. I’m guessing this was my issue.

 

[NegativePanda]

Maybe valve lash then, or did you forget to install the rings?

I pulled the head and found some chips on the header. I’m guessing this is my issue. However, I think I’ll be thorough and double check this as well

 

[sparkwizard]

Do you know what chipped the head like that?
Yes, if that trash was torqued into the head gasket, it might cause a leak.
New gasket, torque to specs, adjust valve lash, TEST COMPRESSION and repeat leak down test before you even put fuel in it.

 

[NegativePanda]

Do you know what chipped the head like that?
Yes, if that trash was torqued into the head gasket, it might cause a leak.
New gasket, torque to specs, adjust valve lash, TEST COMPRESSION and repeat leak down test before you even put fuel in it.

No idea, how or what may have caused that. But I did see evidence of I think of some of the chips. Do you think the header should be replaced as well?

 

[creia]

If you were losing air at the head gasket have you considered flattening/leveling the block deck and the head? (they might not have been true from the factory) I would try that then repeat your leak down test..
Michael

 

[sparkwizard]

By header, are you referring to your exhaust header?
I don't see why it would need to be replaced, and unless something is really installed wrong, I don't think it caused your low compression.

 

[NegativePanda]

So

By header, are you referring to your exhaust header?
I don't see why it would need to be replaced, and unless something is really installed wrong, I don't think it caused your low compression.

Apologies, I meant the cylinder head.