high compression

[400exrules]

1) If i put a JE 416 12:1 in, would i be safe with just HD studs, cometic gaskets, and a stock rod? i know a guy with a z440 with a 13.5:1 piston, and he's got stocks studs and rod and everything, and his motor is stayin together strong.

2) when i pull the cylinder to get it bored, what do i need to do with the cam chain, so that i dont mess up the timing? ive never messed with timing, and ive never had a motor completely apart, ive only installed a cam myself, and i know how critical it is that you have to be cautious so that you dont throw your timing off when messing with all that.

[GPracer2500]

Originally posted by 400exrules
1) If i put a JE 416 12:1 in, would i be safe with just HD studs, cometic gaskets, and a stock rod? i know a guy with a z440 with a 13.5:1 piston, and he's got stocks studs and rod and everything, and his motor is stayin together strong...

The tune of your friends z440 is mostly irrelevent. It's a completely different engine--what works for the Z doesn't mean squat to your EX engine.

Is a 12:1 416 safe on a stock rod and crank? My guess is probably. I think it will depend on how hard you use the engine, the quailty of fuel used (mild deto that a stock configuration could tollerate could push you into a danger zone w/ the config you're proposing), as well as the tolerances and "perfection" of your stock rod. An almost perfectly manufactured stock rod might have 99.9% of it's designed strength. Another stock rod might only have 98.5% of its designed strength. All those differences and more account for how one guy gets away with the stock rod and another guy can't. Using a stonger rod would be good insurance though.


2) when i pull the cylinder to get it bored, what do i need to do with the cam chain, so that i dont mess up the timing? ive never messed with timing, and ive never had a motor completely apart, ive only installed a cam myself, and i know how critical it is that you have to be cautious so that you dont throw your timing off when messing with all that.

Don't worry about it. After the piston and head are installed you'll set the piston at TDC and install the cam. It is at that point that the cam timing is set. Before then it doesn't matter how the cam chain is arranged on the lower cam chain sprocket. Just take some wire, run it through the cam chain, and loop the wire around the frame. That will keep the cam chain from falling down and getting caught up in anything below. Just be aware that as you rotate the crank during the piston/cylinder install that the chain will need to rotate also. But which teeth the chain is timed to on the lower cam sprocket is irrelevent--it's the camshaft sprocket timing that counts.

[400exrules]

Originally posted by GPracer2500

But which teeth the chain is timed to on the lower cam sprocket is irrelevent--it's the camshaft sprocket timing that counts.

why do they make it such a big deal when installing a cam that you keep the chain tight so that it doesnt slip or move from the teeth at the bottom sprocket?

[GPracer2500]

If the cam chain comes off the lower sprocket than you'll never get it back on without taking the right side-cover off. If your side-cover is already off than I don't think it's hard at all to repostion the cam chain on the lower sprocket (can't quite remember though).

[400exrules]

Originally posted by GPracer2500
If the cam chain comes off the lower sprocket than you'll never get it back on without taking the right side-cover off. If your side-cover is already off than I don't think it's hard at all to repostion the cam chain on the lower sprocket (can't quite remember though).

oh, i thought it messed up the timing if it came off and you didnt put it back on exactly how it came off............

k i know im stupid, im just thinkin about all the problems i could run into before i tear my engine apart to get it bored

[GPracer2500]

No, there's nothing stupid about your questions.