Hi all, I have torn down my 94 flhtcu with 100,000 + miles on it. I had the cylinders bored .020 over and had purchased pistons from the machine shop.I am unable to get the circlips in due to the wrist pin being too long.So I ordered another set from drag specialties,they are made by jcc which is chinese,that doesnt bother me.What does is the valve reliefs in the pistons are not as large as the ones from the machine shop.I will be using an ev27 .Should I be worried about piston to valve clearance ?
The pistons are supposed to be stock replacement for .020 with 8.5-1 comp. Its just that the reliefs are not as large as the other set. Heads ,cylinders and case are all oem and not shaved to the best of my knowledge, .045 mls head gasket. Any help greatly appreciated. thank you

 

EV 27 has only slightly more lift than stock, so you're probably OK.

Since you're dealing with parts not OEM however ( jcc?), I'd assemble one cylinder for the purposes of "claying" as a form of valve clearance measurement and roll the motor through a revolution or two. Pull the head and you'll see exactly how much room you're dealing with.

 

I have been researching for like two days. Thank you for your reply.
Tell me if this would even get me into the ball park.
Ive turned the head upside down and set piston on top. I marked the valve stem at the guide,when fully closed. I then pushed the valves up till they contacted the piston,and marked the stem again. I measured marks and got about 5/16" with cam spec saying "3/16 lift tdc" does that mean i have aprox 1/8 clearance ? .130 Does any of that sound about right ?

 

I was getting ready to clay but I dont have adjustable push rods and do have new lifters, this is my first evo rebuild and has been a little tough so far. thanks again for reply

 

Just to ask, have you clayed the pistons? as far as I can tell by your specs. you should be ok. but If I were you I would still clay them to be shure. I do this when putting a motor together just to insure myself. I put together the rear cyc. and turn the motor by hand. saves from bending valves. and why the .045 gasket and not a .030. what cam are you running.

 

The engine is out of the bike,I have hydollic lifters and one piece pushrods so i cant clay, the .045 gasket came in the James kit, and I have an ev27

 

Do those specs seem normal "like factory" ?

 

send me a private mess. and I will give you my phone number