can't find an answer then ask here someone may be able to help!!

zearo, If you are snapping bolts that means that a sideways stress is being applied to them.
They will only tolerate a stretching load.
Something is not right with the way the engine is resting in the frame and the bolts are getting loaded in the wrong direction.

joker, check out these threads.
Cylinder head fastner torque
Cylinder head lapping

Get a new head gasket, lap the head as shown in the second link, and bolt the head and new gasket back on with the correct torque as shown in the first link. Tighten them a little at a time switching from nut to nut in an X pattern until you reach the proper torque.
Ride it moderately for a 10 minutes, let it cool completely, then check for proper torque on the head nuts again. By check I do not mean tighten them even tighter than they were before but rather that they still are as tight as they are supposed to be. Over tightening them will cause damage.
Check the head nuts frequently until everything settles in then they should be good to go for a while. Always check them anyways as a part of a regular maintenance schedule.

ok trying to get this fixed the motor i got was new but some one returned it after drilling 3 holes at rear mount on motor is there any way to fill them in and be good to reuse them

A welder that really knows what they are doing can fill in the holes without warping the cases. The problem here is a welder that has those skills will charge you more than what a brand new engine kit would cost.
Also, with the terrible fish poop/ tofu/ aluminum alloy that the cases are made from the welder will most likely have a few issues to overcome which will raise the overall cost even higher.

I have a 2 stroke that is giving me trouble. Recently it has lost some power and takes a while to get up to speed. I also recently mixed new gas at 18:1 ration. do you think that could be my problem? Anyother thoughts?

18:1 is way too much oil.
A good break it ratio is 24:1. After that initial 2 gallons switch to 32:1 for the rest of the engine's life.

The manula said 16:1 break in then 20:1 it seemed hight to me, everyother 2 stroke around the house is 50:1. I will try a your suggestion. Thanks

you da man!! Worked beutifully. I added 1/2 gallon of gas to my 1 gallaon of 20:1 and it runs like she owes me money!!! Thx.

18:1 is suggested in the manual due to the apparent fact that over in China the vast majority of folks run automotive oil not 2 stroke pre-mix. It is cheaper to get and it will work (poorly) at 18:1 although it carbons up the engine and exhaust like crazy at any common ratio.

I am not good at converting 1/2 a gallon added into a previous 18:1 mix and coming up with the resulting ratio, but I hope that you are. Not enough oil in the fuel mix can ruin the engine.

EDIT: after using this calculator:http://www.csgnetwork.com/oilfuelcalc.html
You NEED TO ADD 0.9 oz of oil to what you have now to get 24:1 Right now you are somewhere less than 24:1 and more than 32:1.

When using proper 2 stroke pre-mix a 24:1 ratio is enough oil to prevent damage to the engine as the parts greet each other for the first time and make happy. After that break in period with 24:1 you are only wasting oil and creating excess carbon so a 32:1 ratio is very good, and the most common ratio used successfully by millions of 2 stroke owners globally.

got bolt stop from breaking ran good for about 2 weeks then coming home motor stop will not fire has gas in take and ging to motor has spark checked it in day light spark looks white

getting gas got spark but nowill not start driving me nuts i dont see anything that will stop it from runing kill switch was the fisrt thing to go

dont know what happened butting bike away dropped it picked it up got on it to put in shed hit clutch got going left clutch go it did not turn over 1 time it was running dont know why its running took it for a 6 mile ride ran great

freind told me that the float could of bean sticking the pin that hold it was sliding out and held float down got gas but not enuff to run but not to run

took a hammer to it today took it out ran good then there was a snap noise and then died would not start got gas and spark comprestion seams good this is motor 2 from boygofast that died on me looks like it time to give up on gas power bike and go back to riding it old way

Norman- I'm not only new to this site, but I'm new to the Intra-Net, so maybe this sort of thing is done all the time. Your "repair center" is a great idea, and I've been wondering why there wasn't something like it. A sort of store-front inside the website. Fine job sir. Do you know of some-one who is similarly interested in 4 cycle information?

Myself and others here are well versed in 4 stroke engines.
Do you have a question?

GearNut- Yes sir I do. If I had read this thread all the way through, I would have known to just ask you. Thanks for the offer. I recently stole my first gasbike for $50. It is a Schwinn Del Mar, with Huashengtaishan 49cc 4-stroke engine, and Grubee stage 3 gearbox. 1) I am using SAE 30 oil in the crankcase, 2) and 2 ounces of, 3) 10w-30 oil in the gearbox- are there better options/amount? 4) What is the spark plug gap? 5) Starting with the needle seated, how many turns out should I pre-set the air/fuel mixture needle? 6) Starting with the screw just touching the lever, how many turns in should I pre-set the idle adjustment screw? My altitude is 5,500' and I weigh 180lbs. 7) Is there a recommended upgrade centrifugal clutch? My pads are worn, and it won't power itself. 8) Any general new guy info. Iv'e never seen one of these before, but it seems to be pretty straight foward. I appreciate your help.

30wt in the crankcase will work fine, but the 10w30 would be better.
Get all the 10w30 out of the gearbox and use ATF or hydraulic oil instead. That will lube the gears just fine and most likely solve the clutch slippage issue as well.
Spark plug gap .022"-.024"
At 5.5k altitude I recommend starting the low speed mixture screw at 1 full turn out.
The air is starting to getting thin up there.
Set the idle speed screw at 1 turn in from just touching.
That should get the engine running well enough to allow you to fine tune it.

No recommended upgrade for the clutch, but some folks like to play with different tension clutch shoe springs and shimming washers stacked on the springs to tune the RPM at which the clutch engages. The only folks I know of that sell a clutch similar to yours are here: http://www.bicycle-engines.com/Centrifugal-Clutch.html or you could look around on ebay.
Only the clutch shoes would be compatible with your clutch as your clutch has a different center portion. You would need to disassemble the new clutch and swap the shoes out.

Definately look at your clutch though before buying any parts for it. There are 2 different clutch designs that I have seen come with the stage III box.
Here is a link to a picture showing the other style of clutch: http://www.ebay.com/itm/49cc-gas-mo...Cycling_Parts_Accessories&hash=item20cebd8eac

You must be sure of which clutch you have before messing with it.

Also, you may need to re-jet your carburetor for your altitude as it is most likely set too rich (too much fuel) in it's factory state of tune.

I am still looking for jets to fit the HuaSheng carburetor to reference you to.

Well versed indeed. I'll use a stock clutch replacement should I need one, there's a local gasbike store. The first link you sent is what I've got. I'm hoping that 2 ounces of ATF will fix that problem though. As for re-jetting, we're at that magic altitude where you almost never have to (atv, snowmobile, lawn mower). Really helpfull, thanks alot!