I have a LT 50 2002 wont start have spark, 120psi

Hey Marty,
An internal combustion engine requires three things to run..(if all the internals are good)..
1. A properly timed spark.
2. Adequate compression (>120psi).
3. Proper air/fuel mixture.

Start by eliminating one of these at a time...(get a professional to clean and set the carb), install a new spark plug. Get a new fuel line.

Hey Nannette.. An internal combustion engine only needs three things to run (assuming all is good inside):
1. A properly timed spark
2. Adequate compression >120PSI
3. A proper air/fuel ratio.

. If you are not starting/staying running.., I would assume/guess that it is still your carburetor.. they are kinda hard to clean.. sounds like the carb is getting fuel but the float bowl is not being refilled fast enough to keep it running...the "needle and seat" may be dirty/sticking..this is what controls the flow of gas into the float bowl,,take the carb to a qualified professional..he can clean and set it... and replace any parts and pieces that need replacing..

Hey Phil, Do you want it to start faster? Sometimes low compression will make an engine slow to start...This is how I would do things in my shop!
FIRST - Have a compression check ran on ALL cylinders - minimum of 120psi on each one!!
Then... New spark plugs.
Have the carbs cleaned and set.
Have the timing set/checked

Have a professional do the work.. you will be glad you did...

Hey Brighette
Its time to check a few things.. First - remove the air filter and see if it runs ok then... if not... have the carburetor professionally cleaned and set... does it run ok now? .. have you installed a new spark plug? .. do that.. if it is still not running ok.. time to check the compression using a compression gauge that screws into the spark plug hole...

Innova Compression Tester

Your engine should pump at LEAST 120PSI. Once you have screwed the gauge in and lightly seated the o-ring.. turn the engine over for at least 5-8 seconds with the throttle WIDE OPEN... 120psi. minimum... if you are not getting very very close to this.... its time to find out why??... it might be that the valves are too tight... but find out why?... this is probably the reason it won't run..

Hey Theresa, IF ALL the items you mentioned are RIGHT...Time to run a compression check,, this will require two people.. and a compression gauge that you screw into the spark plug hole. This will give you an indication of the condition of the internal components..(Piston/rings/cylinder walls - valves/seats/clearance)..Do one cylinder at a time... with all spark plugs removed ...You need to REMOVE ALL SPARK PLUGS ANY TIME YOU TEST FOR COMPRESSION - so the engine will not crank!! Install the compression gauge with the correct adapter (match the spark plug thread length).. seat it lightly so you don't distort the o-ring seal.... now - HOLD THE THROTTLE WIDE OPEN and crank for 5-8 seconds.. the gauge should read at least 120 PSI+...( I have seen some engines run fine with as little as 100psi-rare). If every cylinder checks over 120psi.. that should eliminate the piston/ring valves/seats/clearance possibilities. If any of the cylinders show a low compression or a A LARGE difference between them (over 25psi), time to have a qualified professional look at it...Once you have finished this test, and all cylinders show over 120psi..(+-12psi) ... its time to look back at the carb/choke.. have it cleaned and set by a qualified professional!

New Professional Cylinder Compression Tester Test Kit Mechanics Gas Engine...

Please keep me posted, mark as helpful, thanks

You need to determine what caused it to stop. Is it fuel, carburetor problem or spark, coil problem, or compression, valve or piston problem.
Start by removing the plug, touch the metal on the side by the plug hole, keep fingers clear, turn motor over and look for a blue spark, if good, set plug aside and put your finger over the hole, turn engine ove and it should easily push your finger off by compression. If all, of these are good, you may have gunk in the carb, float stuck or other carb problem. You can also try starting fluid. spray a some at the intake of the carb, you might have to remove the air cleaner, try starting, if it then pops or fires, then it looks like a carb problem, starving gas.

Dean, it looks like your on the right path ,with all 3 things as you stated it should do something, did you try a little starting fluid , you could use a timing light to check for good steady spark . what other kind of work have you done to it ? re check your work ,when you did compression test how did the plugs look =clean =soaked in fuel = nothing at all? Woody.

Some bikes are mad to only start in neutral. It is perceived to be a safety feature. You didn't say what year and model your bike is. Generally speaking, install new spark plug(s), clean the air cleaner, do an oil change, ( with new filter if your bike has a filter ), remove and clean the interior of the carb(s), balance and sync the carbs if two or more, check the compression on each cylinder, ( should be minimum of 120psi and within a 10% range on all cylinders. Check to be sure the battery is in good condition ( if your bike has a battery ). Please rate my answer.

CHECK THE COMPRESSION OF THE ENGINE, IF IT IS AT ABOUT 120PSI AND DOES NOT HAVE A DIFFERENCE BETWEEN CYLINDERS OF 15% THAN CHECK YOUR FUEL PUMP. YOU DO THIS BY REMOVING THE SPARK PLUGS AND FUEL LINES TO YOUR CARBS AND PULLING IT OVER. IF FUEL COMES OUT OF YOUR LINES THAN THE FUEL PUMP IS GOOD. THAN I WOULD CHECK YOUR CRANK SEALS FOR LEAKING

Do you have fuel pressure?

Have you tried spraying carb spray into the intake while cranking the engine over to see if it starts?

If it does than you have a fuel issue.

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa