440 smokin

[booneTRX]

After two tanks of gas my 440 has started smoking. Most noticeable on start up when cold, but it smokes a little when I get on the gas on trails too.

I have yet to change to a synthetic oil after motor work. Does anyone think the oil is broken down already? I wanted 3 tanks of gas thru machine before I change from Honda oil to a synthetic.

Any other guesses at a problem????:(

[TrX465]

400ex's do NOT like sythetic oil bad for the clutch...just stick with some good motor oil...

[crday98]

use Mobil 1 tri-synthetic or synthetic blend.i don't want to start another oil war.the Honda oil is flat out crap.read the thread "400 ex oil"in this forum,it will help answer some of your questions.

[TrX465]

im not trying to start anything either....ive just had good luck with good "car" motor oil...not synthytic or tri-syn. but if you like that right on...i never use honda oil either...

p.s i do change it every other weekend....even though its not needed ....for 10 bucks i have fresh (blood) in my motor

[Blackguywithouta400]

Ok so since this hasn’t been brought up yet I guess I will say something about it. Most of the time when you have a new engine you don’t want to use any synthetic oil in it for a period of time because you want the rings to seat with the cylinder walls and for the valves to seat. You would never want to bore out your bike to a 440 and run synthetic oil in right after the rebuild, because you will have a new cylinder and rings that need to mate, or brake in. If you break in a motor using synthetic oil then it really wont break in because the synthetic is to slick, and wont allow a already small amount of wear. I have been working with engines for many years and we have always-broke engines in with regular oil before going to any type of synthetic. That’s my advice. Then we can get into the debate about synthetic and our clutches, we should know that friction inhibiters will affect the clutches, now weather or not your oil you use has any of the know friction inhibiters that are too slick for our clutches we really don’t know. But we do know that Molly is one of them and is more widely known, Even Honda was surprised because they produced an oil with molly for use in all Honda’s but had to recall the ALL Honda thing, because they found in there CBR600 F4, 929, RC-51 sport bikes that the molly affected the clutches it was able to bond with the organic fibers in the clutch and cause them to slip under extreme loads. There was a TSB on this sent to dealers. Now Honda produces synthetic oil that doesn’t have any friction inhibiters like molly in them. So if your going to use the synthetic oil read the label for friction inhibiters they do list them on the bottle. As for me I will use synthetic oil after 5 oil changes on my 400 I change the oil after 10 hrs of riding, then I will go to 15hr intervals in the HP4 with out Molly.

[TrX465]

not bad blackguy but i still like my regular oil :D ;)

[beerock]

black guy hit it right on the ball. pretty much, use regular oil for break in then use a synthetic after that, the engine will last longer.

once the motor is broken in you dont want the engine to wear at the same rate, so switching to s synthetic will then give you more engine life and ultimately mor epower in the span of the engnes life.

[86atc250r]

The clutch thing is really a myth.. The real issue is friction modifiers. The word Synthetic doesn't equate to "more slippery" like most believe. It really means the oil was engineered to have better properties than that of conventionally refined oil. Regular oil is plenty "slippery", it just doesn't hold up to extreme use as well.

Friction modifiers are used in both conventional oils and synthetics. The important thing is to find an oil that doesn't use any.

The good news is that the oils our air cooled rides like (ie the heavier weights) are far less likely to contain friction modifiers.

Look for the "Energy Conserving" labeling on the back of the container. If you see this, stay away - that means the oil has been formulated to help meet EPA mandates for fuel economy and likely contains friction modifiers. When was the last time the EPA did something good for the performance or life of your machine?

All the research I've done suggests that Mobil1 15w50 contains no friction modifiers. Practical use seems to confirm this (I'm still on the stock clutch afer almost 2 seasons of racing on an engine thats strong enough to regularly outruns Raptors).

Not saying that Mobil1 15w50 is the be all/end all oil, it's just works well, has good stats, is affordable, and easy to aquire - it can be picked up at your local Walmart.

[barbwire44]

Well after the oil dispute, I would say to check youre jetting if that is not the problem then i would say you need new valve seals!..The stock valve seals wont hold up to the heat a 440 puts out. You should have installed viton valve seals when the 440 kit was installed. Alot of guys with the big bore kits are having the same smokin problem.And it is usually the valve seals.:devil

[86atc250r]

Smoke on cold start is usually a sign of valve seals. Smoke on warm running is usually a sign of rings...

That said, it's hard to believe that the 440 has generated enough more heat than stock, especially this time of year & during break-in to have hardened the valve seals after two tanks of gas...

I also have a hard time believing that the engine has suddenly worn it's rings out.

One thing that we've run into is new valve seals not seating properly after a rebuild. One of the 400's we did smoked like a freight train upon cold start, only to completely disapper after a short time. It did this for several cold start cycles until it mysteriously stopped (seals finally seated)...

If it was fine, then just started smoking, my guess is you're using light weight crappy oil (10w40?). 10w40 conventional broke down in my 400 upon break-in within the 2nd tank of fuel. An oil change to 20w50 cured the problem until I was comfortable that the engine was broken-in.

Another thing is if you've recently cleaned & oiled your airfilter, that can cause engine smoke for a little while as well...

[booneTRX]

Thanks Blackguy and Gabe. Very good info. Although I feel funny calling you "Blackguy", I am 100% with you on you post. I will check things out, but since snow is flyin here, time for the sleds.

My ZR580 is ready to rock and my 700 Wildcat I just picked up needs a rebuild.

I wish they could build a quad that would compare to my sleds!!!!! Goin 80 to 100 mph in less than 1000 feet is quite a ride.

Later:macho

[TRFOXX]

I have been using Honda HP 10W-40 since new for 7 months now, should I change to a different oil? I used Mobil 1 synthetic
in my LT 250 and my clutch started slipping. Got rid of it after that!
didnt feel like putting more money into it. What should I use now since my 400 is broken in now?

[Chef]

hey Gabe, my engine builder said that i should NOT use synthetics with the cam i have, is this true? the cam is #55911 by web, any ideas?

you seem to know what you are talking about, so i figured i would ask you

[86atc250r]

Web cam advises against using synthetic on their cams - what an uninformed load of BS.

If synthetic could harm cams, how could any oil manufacturer stay in business with many cars having upwards of 4 camshafts in their engines now days.

Doesn't Web cam advertise that their cams are harder than stock, so you have to harden your rockers? How could an oil that performs better than conventional oils (especially under heavy loads and high temperatures) harm a camshaft that is stronger than the stock unit????..

There's a lot of false, uninformed info out there concerning synthetic oils, and this has to be one of the cheeziest ones.

I've been running on Mobil1 15w50 for around 2 years now on my 400ex - I have yet to have any oil related problems. No flat cam, no clutch slippage (even though everyone says the stocker won't hold up to a modified engine), no leaking seals, etc., etc., etc...