416/426 build.

[2001300exguy]

been out of the seen for a while. looking to pick up a blown up 400ex in the next few weeks and build a nice trail bike out of it. Im wanting to do a 416/426 rebuild with a high comp piston, hd studs, and an off the shelf cam i can find a deal on. My main question is what is the highest compression off the shelf piston made in the 87/88mm size. Im going to be running e85 or e90 so im not to worried about detonation or heat. let me hear your thoughts

[CJM]

Probably 12:1 or 12:5.

I wouldnt personally build something like that-never know if you can always get the gas. Plus its nice to not have to worry about it, pretty much whey I went with 11:1 myself.

[2001300exguy]

my previous bike was a built 416 with 11:1. im very familiar with the 400ex chassis/ engine and loved how the bike felt that why im coming back to one. e85 is readily available around be as is race gas but it doesnt provide the cooling characteristics of e85. i saw je makes a 13:1 88mm but id like to stay with the 87 for revving and reliability.

[honda400ex2003]

as marc said JE has 12.5:1 out of the box. check them out, they would make you a custom one also if you would like.

steve

[bigballz400]

wat bout the e85 with rubber and brass?? i thoguht that wasnt good..........i have no experience with e85, just from wat i was told, it would eat the rubber and brass up in the carb

[Thumpin]

I have ran E85 in my 11-11.25:1 416ex for over 2 years now and its the cats *** for a high compression air cooled engine, with no problems! You will have to richen the carb a bunch and may have to shim or find a richer needle to get the right fuel mixture but it does work very well, keeps that engine very cool!

My advice to you would be stick around 12:1 with the E85, most 12.5:1 pistons require about 110 octane, Id hate to tell you to use the 12.5+ piston and have it not work, take it for what its worth. E85 fuel is around 100+ octane.

The other thing Id add is if you've got lots of hours on your bottomend Id really look into a heavy duty rod with that 12:1 slug, that was the advice Colby at C&D Racing gave me, and he knows his EX engines well.

The stock rod in my 01 EX is the only reason I dont have a 12:1 slug in my own 416!

E85 is much different than Methnol that everyone refers to for eating up o rings, brass, aluminum, rubber, ect. Methnol and Ethnol are both types of alcohol, but are two different animals, plus E85 is a 15% mix of gasoline. So it is so much milder. It is a High Performance Air Cooled Engines Dream, Period!

[DragonGunner]

Originally posted by Thumpin
I have ran E85 in my 11-11.25:1 416ex for over 2 years now and its the cats *** for a high compression air cooled engine, with no problems! You will have to richen the carb a bunch and may have to shim or find a richer needle to get the right fuel mixture but it does work very well, keeps that engine very cool!

My advice to you would be stick around 12:1 with the E85, most 12.5:1 pistons require about 110 octane, Id hate to tell you to use the 12.5+ piston and have it not work, take it for what its worth. E85 fuel is around 100+ octane.

The other thing Id add is if you've got lots of hours on your bottomend Id really look into a heavy duty rod with that 12:1 slug, that was the advice Colby at C&D Racing gave me, and he knows his EX engines well.

The stock rod in my 01 EX is the only reason I dont have a 12:1 slug in my own 416!

E85 is much different than Methnol that everyone refers to for eating up o rings, brass, aluminum, rubber, ect. Methnol and Ethnol are both types of alcohol, but are two different animals, plus E85 is a 15% mix of gasoline. So it is so much milder. It is a High Performance Air Cooled Engines Dream, Period!


Excellent info...