I'm sure it'll run without it but (ther's always a but!) getting it started could be the problem, depending on the condidion of your engine compression, starter, battrey, like I said in the other thread you enquired on, it's there for a reason!

 

I would think not.
Its supposed to reduce compression to help it start easier.
I would think without it, the engine would maintain compression and wouldn't run, but I dunno

 

Mine starts and runs fine. Have had litterally no negative effects from removing it. Mine rattled like crazy so I took it off. Just make sure you take the spring and plunger out of the head aswell.

 

And it isn't on the new 400ex engines anymore I dobt think. That was just a side effect of putting the xr400 motor on the 400ex. It was for when kick starting it. 400s are e start so your good to go.

 

Thanks for the info everyone, that puppy is gone one less part to buy and or make noise. my 400 has a fresh topend rebuild piston kit 11.5to1 comp, valve job, match ported, ported and polishedhead and piston, rejetted, white brothers slipon exh, 3in lowering kit,, uni filter,alloy DG series nerf bars,Renthal handlebars and aluminum hand savers,Procom rev limiter,decompressor assembly removed and a partridge in a pear tree. thanks again.

 

I just checked, and ur right, the new 400x doesn't have it.
I wonder if the head is different and doesn't have the hole for the spring and plunger either.

 

I've heard people saying they've misplaced the plunger and spring and put it back together and it wouldn't start.
How did you remove it and everything still work?

 

If you install a Hot Cam you have to remove it.

 

How did you get the mechanism off the cam?
Press it off or did you do it yourself?

 

Pressed it off with a little shop press. Nothing fancy just took the cam flipped it upside down put a socket that fit on the end and pressed it out catching the cam of course. And it has all these little springs and little pieces that fall off. Then i took a standard size rivit that fit in the extra hole and poped it in there. If you dont your cam will not get enough oil and will burn up. You have to cover the bigger hole. Leave the smaller one alone. Covering the hole actually gives your cam a higher volume of oil and it stays looking new.

 

And to answer your question earlier. The spring and plunger were like a catch for the mech. Without those in place the mech would spin freely causing your valve to be cracked open like it was decompressing all the time. This causing your engine to not start or run beacuse you have massive compression loss. With everything revoved it will never hit the little piece attatached to the right side rocker arm and will never go into decompression.

 

Alright, cool.
I'm gonna get it pressed off at work tonight by the maintenance guys.
Do you think jb weld over the hole would work?