This is my first post, but I have learned alot from reading thes forums. Please be gentle...

My son's HS Moto 110cc 4 stroke (Same unit is sold as a Redcat MPX110) has white smoke coming from the tail pipe whenever he lets off the throttle. It also smokes when he changes gears. Sometimes it the smoke stops, but most times there is pretty much smoke. It does NOT smoke when he is pushing the throttle, only at idle, or when he is slowing down or changing gears.

It is about 6 months old (Christmas present). When it was new, we changed the smelly oil that came in the atv with Honda 4 stroke oil. We then ran it for 30 minutes at idle and changed it. Rode for 2 hours and changed it, then rode for around 10 hours and changed it. It has been changed one additional time, probably around 20 hours.

Thoughts?

 

It sounds like the 'valve guides' are leaking oil; how ever this is usually evidenced by a 'blueish' color smoke. Write down where the oil level is on the 'sight glass', ride it 'normal' for about 5 hours, then note how much oil is required to be added (in ounces) to bring the oil level in the 'sight glass' back up to where it was when you started. This will give you the information as to how bad the 'leakage' is.

One other possibility is that the 'Chinese Air Filter' is a piece of cr-p, and that it is sooo restrictive that the engine is 'starving for air'. If it is a 'paper' type filter - just entirely remove it and run the quad for 5 or 10 minutes (NOT in a dust bowl) and observe if the problem goes away. If it does go away or significantly decreases - get a new 'American Quality' air filter. If this is the problem you probably will have to 'richen' up the carb settings, particularly the 'start, low idle' mixture screw about one turn counter-clockwise, just to get it started.

 

Thanks for the help, NJdale. This weekend, we were riding for a couple of days. On Saturday, we stayed on all flat trails, and rode a couple of hours with no white smoke.

Sunday, we took it onto some of the grades on our property. The property is 220 acres in Kentucky, so we have some flat and some hills, as well as some off camber terrain. After only maybe one or two hills, it began to smoke again. Once again, it is only when he lets off the throttle. I removed the air filter, and it was breathing freely. We still had the same smoke as with the filter on.

It does seem like it smokes more when it is in gear slowing down than when it is out of gear at idle. At idle, it did smoke, but just barely - I had to tke my sunglasses off to really see it. It is a 3 speed semi-auto. I wanted this setup so when my son goes downhill he would get some compression braking, and none of the automatic atv's for the little guys have any compression braking. At 110 cc, it is nowhere near the compression braking the our Polaris has, but at least it does slow it down some.

The oil may have been over full when this started, since the sight glass was completely full, but the dipstick was near the middle. Now it seems like the oil has settled in right around the center of the sight glass. One of the guys I work with told me to just keep it around the middle of the sight glass, that too much oil could potentially cause the problem with the smoke. Also, i have been using Honda oil in it. I also have a Rincon that I switched to Synthetic, so i had some extra regular Honda 10w40 oil to use up. I think the HS Moto calls for 10w30. I don't know if it was the type with Moly in it, but i read somewhere that moly could cause some problems. It only holds a quart, so the difference between the middle of the sight glass and the top is a couple of ounces.

The only other thing - could I be mistaking the white smoke for blue smoke? When i asked my boys what they thought, they said it was white. When i asked if they thought it was at all blue, they said it was the color of the clouds. It was pretty clear at the time. How blue is blue?

Thanks!

 

Well, it's definitely oil, and its probably coming from the valve guides. The 'white' verses 'blue' smoke must be the 'brand' of oil. (most oils normally burn 'blue').

The reason that riding 'on the level' probably doesn't produce the oil burning is two fold - 1, without the 'down hill' - the engine doesn't do any 'engine braking' (very high vacuum produced in the intake since the engine is still trying to 'pump air', but the throttle plate is 'closed' - so it tries to suck air from around the valve guides). 2, With the horizontal engine - the tipping 'downward' down hill probably makes more oil run into the cylinder head valve area, and possibly not drain back quick enough into the crankcase.

A while back, my grandsons 110cc was filled to almost the top of the sight glass and I noticed it giving off a puff of blue smoke every once in a while. The oil level has worked its way down to mid level on the sight glass and I haven't noticed any puffs of smoke lately - so I tend to believe that any 'excess' oil getting to the valve guide area is very sensitive to the oil level on these horizontal engines. The 'little puffs' of smoke won't hurt anything.

 

use less mixed oil with the gas
http://forums.atvconnection.co...id/10/threadid/546274

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eagle atv110
honda 200cc
murray large 6.5 hp go kart

 

<div class="FTQUOTE"><begin quote>Originally posted by: iceman1995

use less mixed oil with the gas
</end quote></div>

These are 4 cycle engines. They don't use an oil/gas mixture for fuel !!!!!

Confucius Says; "Silence is Golden - When you don't know Right from Wong".

 

when checking oil level DO NOT USE THE SITE GLASS, if you are using the site glass when checking the oil level you are over filling the engine with oil and this will cause the engine to burn oil. to check oil level always use the dip stick, unscrew the dip stick , wipe it off then reinsert it but do not tighten. if you'd been using the site glass and adjusting the oil according to it then you will notice on the dip stick it it's overfuild.