stay stock or bore??

[cannondale4life]

Im going to be rebuilding my motor soon because theres a pretty loud tapping noise and its not my valves pretty possitive its my timing chain and tensioner anyways i was wondering if i should go with boring to a 406 or 416 but i really dont want to give up the reliability of my honda so should i keep it stock or is the loss of reliability worth the power gain.

Also whats some of the best mods to go with for me i ride alot of fast woods riding and a good bit of track once again idont want to give up the reliability if anyone can help im fairly new at the 400ex just got rid of my locked up cannondale so im hopefully looking towards a good time on it

any help would be well appriciated thanks

[bpfracin]

i have a 440 it has a bad habit for blowing head gaskets but has plenty of power

406 should be reliable and 416 should be to, but its your choice if it was 416

and were you were talkin about the cam chain and tensior, i was told that is one thing in a honda that was bad was the tensior so just check that out cause u may not need a rebuild

[tri5ron]

Reliability comes with a good maintaince routine, and how a machine is treated, more than anything else.

example, how often the oil and filters are changed, adjust valve clearance's,etc., as well as how often it gets bounced off the rev limiter.
Every machine has a limit to what it can handle.
Which raises a question about why your Cannondale locked up.

A 440+cc at 11.5:1, with a excellent maintaince program, and not over reved or overheated, will outlast a factory stock machine that is abused.

basically, you will get out of it, what you put into it.

[ceballos400]

dude i had the same problem, however, my tapping noise came out to be my piston... took it off and figured i should upgrade while i was at it.... heard a lot of bad stories with the 440s getting over heated... i went with a 426 and really havent had a problem since...i ride/race desert and since im out there for long periods of times, i got an oversized tank to help with cooling... great power, still reliable and running strong

[sprayedgt]

Any engine is only as good as what you put into it. A well built, well thought out engine combo will be just as reliable as stock and make great power. Don't have a shade tree mechanic do your machine work. Spend the extra $$ and have someone with knowledge of ATV engines do it. Go with the 416 if you'd like. Not much of a power gain over stock without any other mods though. But you would still have 2 more bores for later if needed. Put the GT Thunder HD studs in. I know people will say it's not necessary but it's easier to do it now then later. I'd rather have the piece of mind and not need them then blow head gaskets and do it later anyway.

[cannondale4life]

thanks,alot of these replys are makin me lean towards a 416 ,i mean i dont think on any of my previous quads that i run it to hard i never heard the rev limiter on my cannondale or my 400 also i maintance my quad to specs so i should be ok going with a 416

also is the chain tensioner and cam chain a common problem with 400exs and if i rebuild mine what chain should i go with i here many people on here talking about the crf450 chain mod,would that be better than getting like a d.i.d one of ebay for a 400ex

[sprayedgt]

Do the 450 chain. Cheaper than a 400 chain and twice as strong.

[RaceinCircles]

My engine has a tick to it as well...It seems like it ticks more often than the piston goes up and down...any suggestions? I had the head off and everything looked ok to me but I'm no expert. Learn a lot from you guys though...haha

[cannondale4life]

i have no idea what my tick is im thinkin mines a timing chain but i think im tradin my ex for a z400 hopefully its not a mistake

[sprayedgt]

If you're getting rid of a 400 why get another 400? Why not go bigger?

[cannondale4life]

dont have the money

[sprayedgt]

If money's tight keep what ya got and put money into it when funds allow.

[rcatvrider]

Originally posted by tri5ron
as well as how often it gets bounced off the rev limiter.
Every machine has a limit to what it can handle.
Which raises a question about why your Cannondale locked up.

A 440+cc at 11.5:1, with a excellent maintaince program, and not over reved or overheated, will outlast a factory stock machine that is abused.

basically, you will get out of it, what you put into it.

Isn't a stock rev limiter set low to prevent excessive, damage causing revs? I very briefly hit the rev limiter occasionally and was just wondering if this would be of any concern.

[sprayedgt]

You can hold an engine at it's limiter all day and do no damage. It's when you are under load you do damage. The limiter can hold revs back, but it can't do anything with the inertia hitting the engine when it suddenly gets a massive load placed on it i.e a missed downshift.

[cannondale4life]

yea i kinda figured that thats why i was puzzled when someone else in this thred said that to me thanks

[honda400ex2003]

Hi guys, you can't over rev it with the stock limiter and hurt the motor unless it is a missed shift. I would say it is either the cam chain tensioner or the piston also if it has a million hours on it. I have a hotcam in my 416 that makes noise all the time. It ticks like it is hitting. I love my 416 if you are wanting to rebuild anyway. I would do your homework and figure out what you want out of it. I have the stuff listed in my sig and it runs good. I have not raced anything but a stock one that my buddy has just for kicks and giggles and beat him easily but it is a blast to ride. I have the stage 1 hotcam for low end, this is where you need to decide which one you want along with the compression. I can not always get 92 or 93 octane on the trails so I went with 10:1 that way if I have to I can run a 89 octane gas from a station or run 87 if in a do or die situation. I can ride along way on mine but it is just reassuring to know it will work ok without running really crappy. Just my two cents though good luck with whatever you decide. Steve