416 mx motor

[Ironballs]

This is my two cents on what I believe works good. I have a few races on this set and could not be any happier with the results. I used a 416 JE 11-1 piston stage two Hot Cam fully ported head, and a timeing key. I run a Uni filter and pro circuit full system. I used the thin base and head gasket from cosmic. I did notice when I put her together the piston still had .030 deck clearance. So I think if I did it again I would mill the jug down a little to get better quench. I did run her at first without the timeing key, but that really seems to help so I would highly recommend it. I run race gas, and the stock carb with a DJ165 main a 42 pilot, with the choke out. I switch back and forth between the K-N and the Uin and can not tell any difference. I also shorten the pipe, but could not really tell much difference there. So I would not really recommend it for anything other then looks. Also I run stock gearing with 18” klaws. This setup will really helps the hole shot, and pull like mad out of the corners. I would like to add that the hot cam came with a gear flange built into the cam and so for the lash has been staying right on. This kit was very easy to install. I bought the parts at C-D racing these guys our great to deal with. As with any motor the port work is very important so if you do it your self be careful. I used 80 grit cartage rolls and a die grinder. Then hand polished with 120 girt sticky sand paper that will stick to your fingers. One more thing I installed a Barnett clutch while I had it apart. This whole set up cost less then $550 and took about a week of evenings and a few beers. I only posted this stuff to help people who are wanting to Know if a 416 can run with the big dogs and I think it can for the time being.
:) :)

[Silverfox@C&DRacing]

Just an FYI you might run a colder plug if you aren't already doing that, the degree key makes the bike run hotter..

I am glad that you are pleased with the set up :D

Pretty much what is in my bike and it runs strong

[redroost85]

Wow, Ironballs, that was a great write up! I was(am) tossing around what to do to my motor over the winter. Now I have a really good idea. Thanks for all the info man and good luck to you.:D

[2001 trx400ex]

how many degrees did you time it ahead and how much difference did it make.

[Ironballs]

Originally posted by 2001 trx400ex
how many degrees did you time it ahead and how much difference did it make.


I used the sparks +6 degree key it's about 25 bucks with the side cover gasket from C-D racing, I think it's a good bang for buck mod.

A difference you can feel on the track.

[2001 trx400ex]

where do you feel the power gain in the powerband.

[Ironballs]

It adds power throughout. Improves the throttle response when you pin it coming out of the corners.

[Glamis400ex]

I have same set up minus the degree key and am very pleased with the results.

CD Racing is also the BOMB to deal with. Hi Dusty..(wink);)

Glamis

[Ironballs]

One more thing I found out the hard way, make sure your silencer is packed tight with packing. Believe it or not this is necessary to keep the exhaust flowing at is best.

[TRXMaddness]

Iron Balls... with the JE 11-1 piston did you have to do anything with the stock bore. I'm looking at doing some work to my motor here very soon and I just curious about the bore. I know I will probably have to press the sleeve out and replace the stock sleeve but I was just curious about the bore.

[Ironballs]

Originally posted by TRXMaddness
Iron Balls... with the JE 11-1 piston did you have to do anything with the stock bore. I'm looking at doing some work to my motor here very soon and I just curious about the bore. I know I will probably have to press the sleeve out and replace the stock sleeve but I was just curious about the bore.



The 416 bore JE piston is a +2mm overbore. It uses the stock sleeve. That’s the reason I went with it over a 440 kit. I paid the local bike shop 45 bucks to bore and check the ring gap. This is a lot cheaper way to go then to replace the sleeve and still have to bore it to the finish size.

One more thing I forgot to say, air box lid and water snorkel are removed to get enough air flow to filter.

Any body know of any MX racing this weekend in southern IN?
Quad City race got cancelled.
:confused: :( :(