My son rides a 90cc Sundiro - it's very very similiar to an Eton. I bought it two years ago off someone else, so I don't know where the original dealer is, but Eton went out of business anyway, so I doubt that would help.

I just moved from GA to AL and after the move, I went to ride with my son, and his ATV started very rough (coughing every 2d stroke and choking when I added gas). It finally improved after I let it run for a while, and we rode down the street. About a block later it just quit. I haven't been able to start it since, and it has been 4 weeks. I looked at all the normal things - gas, oil, spark plug, etc. My father-in-law looked at it as well and he thinks a valve may be stuck.

I have been trying to find someplace to take a look at the bike, but none of the dealers around here will touch it since it's not their brand (ie - Polaris, Honda, Kawasaki, etc). I need some advice - his ATV is just sitting there as the summer fades away!!

 

Perhaps the local dealer went out of business but E-ton is alive and well.I don't know much about your bike but isn't it a two stroke engine?Two strokes don't have valves.Is the spark plug sparking?Is it wet or dry?We need some more info to help out.

 

The full model name is Sundiro XDZ90ST. The engine is an air cooled 2-stroke, 82cc displacement, bore x stroke is 50x42mm, a compression ratio of 6:1, and it has an automatic transmission.

The spark plug is sparking. When we pulled off the air filter box, it doesn't feel like there is any suction in the engine compartment - it didn't suck with a hand over the opening (where the air filter connects) when we tried to crank it. That is why my father-in-law thought a valve might be stuck. It's getting gas (we checked the fuel line). The engine turns over, but it won't cough to life. It has an electric start, but the battery died, and we've just being trying to crank it by using the kick start (which my son normally can do just fine).

It has one of those safety straps that allow you to kill the engine when you pull it. It connects by a rubber cap to the back. It's come loose before, but I checked that several times, and I'm pretty positive that isn't it either.

 

Is the spark plug wet or dry?Just trying to figure out if its getting too much gas or not enough.Also do a compression test.Should be somewhere between 85 and 120 lbs.With the gas turned on if you put your hand over the carb and crank it your hand should get wet with fuel as your hand is now a big choke.If you open the throttle you should feel some suction on your hand.If I understand you right it still runs but runs poorly?

 

Hawkdriver - My son also rides a Sundiro, exactly like your sons. A friend of mine also has one. We've put some miles on 'em already, with no real problems so far. We've had to replace plugs once in each.

You've already tried everything that I can think of trying! MAYBe a reed valve is stuck. I would try the hand over the carb throat thing mentioned above to see if there is any suction on your hand.

Good luck, and keep us posted on what you find out.

Sorry I couldn't be of help, I ll mention it to my friend that also owns a Sundiro, and see what he says.

Oh yeah, I had a problem like that once. I forgot to turn the gas ON.[img]i/expressions/face-icon-small-mad.gif[/img] The tether coming undone got us once too.

FYI - Your Sundiro is the exact same as a Predator, except for the plastic.

 

hawkdriver you sundiro is the exact same quad as the articat , predator,bombardier , kasea, e-ton . find a friendly dealer or tech and pic there brain . the company that makes these bikes for sundiro is nusun try a web serch for it . if all else fails try calling my dealer he sells sundiro . its called cow town usa inc. 573-885-6300 or try cowtownusainc.com
we have had no trouble with ours so good luck

 

Here's an update - the bottom line though, is I still haven't figured out the problem. First - thanks to you all for your input and help!

I spent the weekend camping with a friend from Tennessee who has been playing with motorcycles all his life. I took the Sundiro with me to see if he could figure it out. After changing the spark plug, taking apart the carb (it was very clean), checking the suction on the carb, checking the fuel flow, and a couple of other things, he concluded that the engine isn't getting any gas. It sparks, and it sucks, but for some reason fuel is getting into the chamber. The fuel filter and fuel line are clear, and yes - the fuel switch is on (we tried it both in the reserve and on positions). His hand wouldn't get wet when he held it over the carb and we tried to crank it, even with hitting the gas pretty heavily.

He speculates that it may be the reed valve (in fact, he cannot logically come up with anything else).

03Ozark - you suggested this as well. I'm not that familiar with these engines to fully understand what a reed valve is. Does anyone know how hard it might be to replace and how much one might cost?

Thanks for the help!

 

Boyesen makes aftermarket reeds. They show them as for the Predator 90, but it is the same motor. They are not expensive. I couldn't tell you how to change them though, sorry!

 

If you follow the peice that the carb attaches to where it bolts to the engine block that is the reed block.Just a few bolts and it should all come right out.You may have a broken reed or something.It could also be low compression or a blown seal as well.Did you test the compression?

 

I haven't tested the compression yet - I have to find someplace that will even look at it. So far, no one will look at the bike. It seems to have pretty decent compression.

However, I called Cow Town USA (reccomended earlier in this thread) and they say they have NEVER seen a broken reed and it's almost always a seal problem. They told me to get a compression test first (again - back to my problem that no one will take a look at the bike).

I think I may just order a new reed and replace it to see if that fixes it. If it's not a seal and it's ultimately a blown seal, how difficult could THAT be to fix?

Again - thanks to you all for suggestions!