rebuild...

[EvilMaximus]

so my wife engine in her 400ex blew up and need to be rebuilt...i was think of going with a 416 or 426 and a stage 1 or 2 hotcam...which would be more reliable...all she rides is dunes and a little bit in the woods..no racing or track...later i will be getting a slipon...im not interested in a 440...any ideas?..sug..?

[zrpilot]

416
JE 10.8:1
HC stage 1
CRF450 timing chain

If done correctly, it would be reliable and pull like a sum beeotch!

[Honda#4]

I want to go with the samething Pilot said but running 11:1 comp and a Stage 2 cam.

[EvilMaximus]

any others...anyone have a 426?...i cant seem to find a kit with a 415 and a stage2 cam..ive found a 426 with a stage 2...is the 416 a more reliable bore?

[zrpilot]

The 426 is the max you can go before re-sleeving. I think the 416 is more reliable because the cylinder is thicker, besides an extra 10CC is not a HUGE improvement.

Also if the 416 needs to be re-freshed, you can always go up to the 426 without having to re-sleeve.

Just my $.02

[Chino886]

Originally posted by zrpilot
The 426 is the max you can go before re-sleeving. I think the 416 is more reliable because the cylinder is thicker, besides an extra 10CC is not a HUGE improvement.

Also if the 416 needs to be re-freshed, you can always go up to the 426 without having to re-sleeve.

Just my $.02

I'll second what ZR is saying! :devil:

[vett_09]

Originally posted by zrpilot
The 426 is the max you can go before re-sleeving. I think the 416 is more reliable because the cylinder is thicker, besides an extra 10CC is not a HUGE improvement.

Also if the 416 needs to be re-freshed, you can always go up to the 426 without having to re-sleeve.

Just my $.02

He's right.
Where are you looking for the kits at? Because you shouldn't have a problem finding a 416 kit with a stage 2 Hotcam.

[Honda#4]

The only place i've found a 416 kit with a Stage 1 or 2 cam is Goldenwestcycle, it's $330 for it but it's alot cheaper to buy from Colby.

[Old Head]

I'd probably go with the stage 2 at the dunes cause you probably spend more time in the upper gears. But it all depends on how she rides. Wide open (stage 2) or does she just put around (stage 1)

[JOEX]

The piston kit and cam can be purcahsed seperately.

Check with C&D Racing (http://www.exriders.com/vbb/contact.php)

[AbnMP13]

This (http://cgi.ebay.com/ebaymotors/New-OEM-Honda-CRF450R-Cam-Chain-CRF450-Timing_W0QQitemZ320089945026QQihZ011QQcategoryZ355 95QQrdZ1QQssPageNameZWD1VQQcmdZViewItem) will work on a 06 400ex?


Originally posted by zrpilot
416
JE 10.8:1
HC stage 1
CRF450 timing chain

If done correctly, it would be reliable and pull like a sum beeotch!

[ex_freestyle]

not to steal EvilMaximus post but i have the same problem i melted my piston in the trusty ex which almost made me cry seeing that none of my friends ever blew or melted there piston in there ex but theres cant run with a ds650 and stay ahead of one eaither any who im boaring mine to a 426 and is there any other way to get extra power out of it with out stroking it i have hotcam stage 1, timming key (4 degrees), port and polished, and ya thats about it is there anything i can do to get more jam out of this thing

[zrpilot]

Originally posted by AbnMP13
This (http://cgi.ebay.com/ebaymotors/New-OEM-Honda-CRF450R-Cam-Chain-CRF450-Timing_W0QQitemZ320089945026QQihZ011QQcategoryZ355 95QQrdZ1QQssPageNameZWD1VQQcmdZViewItem) will work on a 06 400ex? That is the same one I used, worked great.

[zrpilot]

Originally posted by ex_freestyle
not to steal EvilMaximus post but i have the same problem i melted my piston in the trusty ex which almost made me cry seeing that none of my friends ever blew or melted there piston in there ex but theres cant run with a ds650 and stay ahead of one eaither any who im boaring mine to a 426 and is there any other way to get extra power out of it with out stroking it i have hotcam stage 1, timming key (4 degrees), port and polished, and ya thats about it is there anything i can do to get more jam out of this thing

450R carb
8 plate clutch kit

Also I think I would NOT run the advnace key, they produce a lot of heat and maybe that did your piston in...???

[AbnMP13]

Is it necessary to change it or just recommended?

[zrpilot]

What are you referring to?

[AbnMP13]

Posted that in the wrong thread now didn't I.

I was asking if the HD cam chain was necessary or just a precaution.

[zrpilot]

in my opinion the HD cam chain could be both a precaution and necessary, depending on the age of your 400EX. If it were old, then for sure I would replace the cam chain.

[AbnMP13]

It's an 06 so I'm gonna check the local shop to see how much the CRF 450 cam chain is when they open today.