What is the Best piston for 416ex

[charette14]

I want to do an over-size 416 on my 400ex after my season in mx, but I don't really know what is the best compagny of piston... I know that there is a lot of people they like WISECO. But, I don't want this, I just want to have a better piston little bit more heavy than the WISECO.

Now, my motor only have a K&N with jet-kit and an exhaust Trinity Racing Stage IV.

After this season I will do my over-size to 416 and... put a CDI rev-box, a degree-key +2, some spring valve heavy-duty by Trinity Racing, a hot cam and my mecanicien will do a good porting. So with those modification what will be the best piston?

I don't want a piston Hi-Compression!

[underpowered]

you will be hard pressed to find a 416 piston that is no high compression. Why dont you want high comp? you cah run up to 11:1 on pump gas, 93 octane.

as for brand, JE makes great stuff, Ross is a lighter piston and great quality. What do you mean you want a heavier piston than wiseco?:confused: a lighter piston will rev quicker and is better in most cases, a heavy piston will just slow your engine down.

you will have to rejet with the mods you plan, but i would not do a degree key with a Big bore engine. it will just make it run hotter. i would also be careful on what CDI you run, stay away from white bros. or any XR250 Box.

[charette14]

Thanks.

I don't want a hi-compression piston because a lot of people said to me that will pop the stud of my head cover. Is that true ou not? I don't know because I didn't try it. Thanks for the compagny of piston, I will look... for a lighter piston now. The degree key is not good? I will not put that if you've said that make it run hotter. For my CDI, I will look for the Trinity Racing Dyna Ignition. Is that a good rev-box?

I do mx race and I have this on my bike now: a-arm lone-star +2+1, elka shocks sports and racing serie tripple spring, rpm axle +2+2, nerf-bar ac pro-peg, fat-bar pro-taper, wheels douglas beadlock, pipe trinity stage IV and lot of little thing....

What do you suggest me to do with my engine if I do MX race. Because after this season I will continue to spend money on my bike. I want some good performance but I want a reliable bike too. So what are you suggestions?

[400 SS EX]

From what I've understood over the years you risk the head ' popping' off due to a high compression piston once you start to go to 12:1 compression or higher. I'm running an 11:1 right now going on about 6 months no problems and I just run premium gas from any old gas station. If your going to put in a bigger bore you might as well go with a little higher compression. Hope this helps with you piston decision.

[450Rchaser]

10.8:1 JE piston is what I have and everything is fine.

[quadkrazy400ex]

i have a ross racing 416 piston .. 10.8:1 and have had no problems so far with it and its been a little over a year since i put it in

[charette14]

Allright thanks a lot, that's really help me... I will try the ross racing 416 high compression piston 11:1

But only after my season ;)


Ciao

[SHADETREE101]

i am running a je 13:5:1 compression piston for three years now with no problems. never blew a head gasket. most heads are over tightened and pull the studs out. however you must give it a lil extra for the added cylinder pressure. stock torque is 33 ft.lbs. i torque to 40 ft. lbs. never had a problem i also ruun the xr gaskets and no base gasket making my bike around 13:9:1 compression. i also ran nitro alcohol which produces alot more pressure than gas. i believe it is all up to your engine builder. its all about whay he is comfortable with.

[Def-e-nition]

Originally posted by charette14
a degree-key +2,

Hi. Could you guys please inform the uniformed , what this is ?

Something that advances timing ??

I've seen you guys speak a lot about it , but never bothered to ask .

Thanks .

[underpowered]

Originally posted by Def-e-nition
Hi. Could you guys please inform the uniformed , what this is ?

Something that advances timing ??

I've seen you guys speak a lot about it , but never bothered to ask .

Thanks .

yup, rotate the fly wheel two degrees forward to advance ignition timing.

[jsmith2232]

Ive been running the je 10.8:1 and havent had any problems at all.