GIO 49cc 2 stroke dirtbike - NO start after 2 great runs!

[Brainsquishy]

Weld & Fastdoc, thanks on the congrats...I've chosen to live on the cheap for a very long time to get to this point.

I will attempt a shaft repair shortly and post the results.
Thanks

[Bobby-V]

I've got one of these machines too. I'll be checking the fly wheel tomorrow for sure. So far I've had no issues at all. I also find that I stick with the suggested 25:1 mixture (Lucas synthetic) and it fires no problemo.

I am also going to search ebay for a new flywheel. I want to keep that machine running as long as possible. Mind you, I do know I can get replacement motors on ebay for $50 so that in of itself made it worthwhile.

Fortunately I can get it shipped to a place in the US and drive down to pick up. Saves huge $$ on shipping to Canada (which is sometimes more than the products I've purchased)

[Weldangrind]

I presume that you mean Sumas. It seems like I'm picking up a package at Letterlock every week lately.

[jaloos]

I have had alot of experience with these little engines, they are the same engines that come in the bulk of the chinese pocket street bikes.

As with anything from China you MUST go over them with a fine tooth comb and blue loctite everything. It is a good idea to swap over all the bolts with quality real steel or stainless ones. The sooner the better as a stuck Chinese cap screw will more often than not snap before it ever comes loose.

The rocket key issue may have not been the fault of a loose nut on the flywheel and may have been too small of a rocket key for the slot size. I have had one twist out on me as well. The shaft was ok but the flywheel was junk. A new flywheel and proper size key rocket or otherwise may still work. As far as buying a new flywheel alone I would buy a whole engine for the parts, cheaper in the long run.

Very good site for dealing with these engines is

http://www.pocketbikeplanet.com/forumdisplay.php?f=82

They are predominantly pocket street bikes but a ton of info on these engines from mkust do's to performance mods.

I would however also caution you as to the oil mix 50 to 1 is far to lean a mix for these engines esp. in the break in stage. Break in should be between 25 to 35 to 1. Any less oil and you will cook these little guys.

A good first for these bikes is to flush the tank out, replace fuel lines and add a good filter. The little petcock on the carb is junk and I take them apart fill the guts with JB weld and re drill the hole that passes through them. The rubber in the shut off is prone to cracking and gets into the carb and plugs off the needle and jet.

To tell you the truth I have for the most part gotten rid of all the junk carbs and swapped them all out for a walbro style pumper card with low and high adjustment needles. This removes all the floats, jets and the associated hassles of tunning the carbs. You will have to re plumb the fuel tank to take a return fuel line and do a little work to get the throttle cable to work right but well worth the hassle. As I said before these carbs are junk and if let sit too long will need cleaning before it will run decent again.



Check out the site I posted earlier it will get you tons of info on these engines.

[Weldangrind]

Wow! Thanks for sharing your experience, jaloos. 8)

[jaloos]

No worries, lots more info on that forum link.

PS when you replace the flywheel use a business card to set the coil gap.

[Bobby-V]

Well after setting up some photos for the throttle limiting trick on my pocket bike I broke the petcock on the carb. Time to replace the carb for sure.

Something else I found is the ignition wire is a little finicky. It seems the spring looking hoo haa that connects to the plug has a bit of a thing for missing it's connection with the copper in the ignition wire.

I love it but it's finicky. And that in of itself makes it fun.

[Bobby-V]

Just found the original carb for $12 free shipping to US. I love living close to a border town. Ten minute drive for free shipping is better than walking down the street for $50 shipping.

I was looking at this thing too, that is if my son decides he doesn't want the machine.

http://www.ebay.ca/itm/LIGHTENED-FLY...ht_4120wt_1110

[jaloos]

Originally Posted by Bobby-V

Well after setting up some photos for the throttle limiting trick on my pocket bike I broke the petcock on the carb. Time to replace the carb for sure.

Something else I found is the ignition wire is a little finicky. It seems the spring looking hoo haa that connects to the plug has a bit of a thing for missing it's connection with the copper in the ignition wire.

I love it but it's finicky. And that in of itself makes it fun.

The wire in the coil can be replaced with a good 8mm wire and boot. Just unscrew it from the coil, trim down the 8mm wire a bit to make it fit and screw the new one on. I do it to all my engines as a matter of course since the wire is junk lol basically 3 or 4 strands of solid wire with poor insulation.

[jaloos]

Originally Posted by Bobby-V

Just found the original carb for $12 free shipping to US. I love living close to a border town. Ten minute drive for free shipping is better than walking down the street for $50 shipping.

I was looking at this thing too, that is if my son decides he doesn't want the machine.

http://www.ebay.ca/itm/LIGHTENED-FLY...ht_4120wt_1110

The lightened flywheels are ok. You can do it yourself by starting the cut off with a dremmel then snapping the fin off. Be careful of these as the lighter you make the flywheel the less rotating mass you have. Less rotating mass will give you higher rpm but will also make it harder when pull starting it. Keep in mind as well the fins are there to cool your coil and head.

[Bobby-V]

Thanks. Right now I am preoccupied with slowing the machine down for my son. Once he's ready though I want to unleash this thing......it's got some potential.