My son has been running his Gio for a few months now, but lately I am noticing that it is harder to start and once I close the choke off, the bike will often stall out. Seems ok when he has the throttle to it, but stalls out when sitting at idle. I have tried adjusting the idle screw and the air(?) screw beside it, but haven't been able to get it like it was when we first got it.

Any suggestions?

 

if it use to run good and it doent now, probably need to take carb apart and clean it good, try this first.

 

All of these 50cc quads will need valve adjustments at least once a year or when they have problems starting and losing power. So either the carb needs to be cleaned or valves adjusted. The valve adjustment is the most common and what you describe is what happens with the valves or dirty carb.

 

do the carb first, tiny jets mean problems with dirt etc. do not open up the valve covers unless its a last resort, to many people are "adjusting" the valves with little or no reason, the damage that can be done isn't worth doing this as the primary source of issue. Make sure the air cleaner is not plugged with dust, check / change your spark plug, clean your carb, put on an "inline" fuel filter, then see how its running.

 

oldkawi,

The most common problem with these 50cc quads is valve adjustment. There is no damage that can happen by adjusting the valves. These need to be adjusted about once a year. Yes the carb could be the problem but the valves are more likely to be the problem with these. I guess the carb would be the easiest thing to start with but if you do a compression test first it can eliminate the valves or not.

 

Thanks for all the replies. I have heard fairly often on this board that the valves on these bikes need to be adjusted. I am going to try cleaning the carb first, but I was wondering if there if anyone is interested in posting a step by step on adjusting the valves? How complicated is it? I am not exactly a small engines guru...but I can follow instructions ok.

 

I second the valve adjustment, these small 4 steokrs are touchy and like there valves set correctly, do the carb and also check the valves...

 

if your desparate to adjust the valves, take off the two covers protecting the rocker arms, they are equal in size top and bottom (I like to stand it on its back wheels against a frame for this) take a feeler guage (combo of feelers to make .028 mm) make sure you have the right sizes) take out the spark plug, turn the piston to top dead center, (use a rod or wire to find this) loosen off the nut on the rocker, adjust the rocker outwards, slide the feeler guage in between the rocker and valve spring tighten the rocker to JUST touching the feeler guage, retighten nut, repeat for the other replace everthing you took off. put it back on all 4 wheels start, listen for excessive valve noise after 35 seconds, if its ok , great otherwise repeat.

We've got 4 in the yard 6 more I service, other than ONE machine we were fooling with to make more power realistically they have "never" needed adjustment other than I like to tinker --the carbs have, the plugs, yes inline fuel filters have definately helped. Do what you have to but at 2500 to 3500 hours on 8 machines they have not really needed valve readjustment We are now starting to have small cvt adjustments to make, thats it, and they have been pounded this year by 11 and 12 year olds who have been told to run 'em hard these are tough little machines