What should i do?

[chris_bchs2007]

Okay, so i got this 03 400ex off a kid... it smokes from start and the whole time its running... I know its in the top end, and i also know the bike has a high compression piston in it... A mechanic at the honda shop is going to do all the labor for 100$... this is an amazing price because i told him i was going to bore it to a 440 and he is going to bore the cylinder and everything for the 100 bucks... my budget isnt exactly limited, but its not huge either... im not crazy about power, but im a bigger guy and would love to whoop up on my skinny friends when i race them... the mechanic told me it sounds like the cam chain is loose or stretched or something... the bike starts just fine and seems to really have alot of power already ( i have owned and road other 400ex's)... the biggest reason i want to bore it is because of the price he is giving me on the labor and my friends keep persuading me... what do i need to order just to fix the bike? or should i just 440 it, im going to put a stage 2 cam in either way b/c hes going to install it at no extra cost... the reason im weary about doing the 440 with the 11:1 piston is because there just seems to be alot of problems and money that can be involved with it and i know that doing the extra work really seems to hurt the reliability of the bike... i just want this thing fixed and not have to worry about it anymore... what you guys do if you were in my shoes?


recap of questions:
what do i need to just fix the bike?
should i just 440 the bike?


thanks for any input guys

[madmartin]

valve seals or rings should fix the smoking.
a new timing chain if it's stretched.
double check your mechanic, sounds too cheap for a shop mechanic even if he's doing all that work on the side. Theres also a lot that can go wrong when the person doing the work is'nt as good as he thinks he is.
I love the big bores. for every person that runs one and says there fine you'll find two people who don't run them and say they're unreliable. It will give you the low end to move some one of your size. It will also compliment the cam greatly. heavy duty head studs and timing chain and an aftermarket oil tank are all you need to make the kits reliable. Sorry and a good gasket set not the ones on ebay for $5 that are made by a six year old in china.
If you have problems with these kits then theres something you missed. How can everybody else run them without problems but because one individual can't there something wrong with the kits. Don't worry bore it out and laugh as your pulling away from your anorexic friends.

[fastredrider44]

CRF timing chain upgrade. Heard good things from them, but never done one.

[fastredrider44]

Also don't skimp out on the head. Go through the valves, replace them if need be, or just have them ground, and have the seats cut too. Amother piece of advice. On the gasket kit, try to use as many gaskets as possible. Don't discard of the "extra" gaskets and seals. They put them in there for a reason.