Predator 212 build questions

[Planominibike]

I am trying to build a predator 212 drag motor for minibike I'm running a 285 series cam from nrracing with chrome Molly pushrods billet rocker arms and also have stainless steel valves from nrracing the lash caps I installed seem to be wearing a little funny and I noticed that the rocker arm is mostly rubbing on the upper half of the capI have pushrods that are 5.110 inches long and I have milled the head .065 do I need to get shorter pushrods

 

[Planominibike]

If I reinstall my stock rocker arms instead of the 1.2 ratios billet arms it seems to put contacts on the right part of the lash cap. Is this wear do you to just running different ratio arms

 

[OND]

I would say yes...Russell at NR racing has cut to length moly pushrods. Good Luck !

 

[Planominibike]

Do you know of any easy ways to get the measurement for the links pushrod I need or should I just buy the cut to length and take a little bit off at a time until it works

 

[Prowler08]

You could try gx160 lifters also...

 

[OND]

Do you know of any easy ways to get the measurement for the links pushrod I need or should I just buy the cut to length and take a little bit off at a time until it works

That would work...you need to get the rocker arm centered to the lash cap with the valve 1/2 opened. Hope that makes sense.

 

[Planominibike]

You could try gx160 lifters also...

Do you know by chance how much shorter the 160 lifters are, I happen to have a 160 I could use as a donor

 

[OND]

Sorry I don't know exactly how much shorter they are, but they are shorter forsure. I run a set of gx160 lifters in a gx200 honda open engine ...block and head milled .080 all together but with raceseng 1.3 rollers. The reason I used them was less weight than the gx200 lifters.

 

[Prowler08]

Roughly 3/16" to a 1/4" shorter, can't remember exactly...

 

[Norcalputput]

I'm not sure how many times you will be able to take the pushrods apart they are pressed together but the raceseng adjustable are the way to go


Sent from my iPhone using Mores code

 

[Planominibike]

Think I am going to try the 160 lifters then I will have two length lifters and three length rods to try and get something of a overall length needed, thanks for any and all help

 

[Planominibike]

Okay I am running into a few problems , I removed the 160 lifters and put them in my predator I cannot seem to get it any lengths that seems to work I get the shortest lifters and rods I have there either too short and don't work or the ones that do work still hit the top of the lash cap. It almost looks like the stud is too close to the valve it looks like it needs to be a little bit further back when I compare to my stock rockers the contact point seems further away. I also noticed that my cam lobes and my lifters have where marks on them after only a few minutes of running.

 

[OND]

I have run into rocker arms hitting the lash caps before , and the high ring locks always seem to work for me. I'm not saying this is the problem you are having...but It might help.

It kinda of gives you more clearance like the valve on the right side...the one on the left has centered locks.

Hope this might help.

 

[Planominibike]

View image in gallery​

Looks like the center line of the contact point is further away from the stud than my stock rocker. I know the push rod side is shorter because if the 1.2 ratio but the valve side should be the same distance right?

 

[OND]

Sure looks like it longer.