Why is fuel not getting to spark plug on my yamaha raptor 50cc?

If you mean Raptor 350 then its normally under the seat behind the battery

Check tap filter and carby.

check fuel flow and check spark at spark plugs

According to an "ATV Rider" 2009 article, "When the Grizzly was introduced in 1998 as a 600cc machine, the top was blown right off the displacement wars of the time."
It was replaced in 2002 with Yamaha Grizzly 660, an even bigger engine derived from the well-established all-terrain vehicle (ATV) Yamaha Raptor 660R.
Grizzly's 660 cubic centimeter (cc), four-stroke, liquid-cooled single overhead camshaft, five-valve engine performs well in open country, but sometimes it causes serious problems for owners.
Before you call a Grizzly dealer, however, trying a few tricks in your garage can save you a lot of time and money.

Check the fuel level.
Locate the fuel meter indicator on top of the multifunction display.
If it does not work properly, open the fuel tank, and push the Yamaha 660 Grizzly side to side.
Ensure the fuel is not contaminated by water or rust.
If you have not driven your Grizzly 660 for a long time, drain the tank completely, and fill it with a fuel tank cleaner.

Check fuel hoses for cracks or leakage.
The hoses should be soft and simple to bend.
Replace those that show any sign of wear.

Check the compression.
Screw a compression tester into the spark plug hole, and press the electric starter button.
If no compression exists, contact a Yamaha dealer.
Wipe wet or dirty electrodes with a dry cloth.
The spark plug gap should be checked regularly

Correct the spark plug gap.
Measure the gap with a wire thickness gauge.
If necessary, adjust it to 0.8mm using a screwdriver or replace the spark plug.
Use only a Yamaha-specified spark plug.

Check the Yamaha 660 Grizzly's battery.
Operate its electric starter.
If the Grizzly starts quickly, then its battery is in good condition.
If the engine turns slowly, check the battery lead connections, and you may need to change the battery.
If the engine still does not eventually start, your Grizzly is beyond home repair.

You need to check if you have spark and fuel:
1: Remove spark plug and fit it back in the plug cap, crank over to check spark

2:If you have spark check to see if plug is wet or dry
(a)If dry, there is a fuel issue and you need to check by the carburettor and tank for fuel and/or any vacuum hoses not connected.
(b)If wet you might have a faulty plug or flooded in which case try starting with full throttle and no choke(if Manual choke)

3:If no spark, look for the cutout switch(normally on the right hand side handle bar) to make sure it is on and that there is no water residue on any HT leads etc.

Check the compression, pull the spark plugs one at a time if more then one. If you don't have a compression gauge, you can put your figure over the spark plug hole, be mindful that before it blows it's going to **** so make sure that you don't hurt yourself leave a little gap so your figure doesn't suction down to tight. If your getting compression it should **** and blow pretty hard. If it seems to have good pressure and suction. You might need to check your timing, also make sure that you can feel air moving out the exhaust, might not be able to with the pipes on it but if it won't start and your getting everything else it needs to run gas,spark, etc. It has to almost be timing or compression.

hi there.see if this link helps you get it sorted.
2002 yamaha raptor and it wont start Google Search

Try intoducing a small amount of fuel (half a teaspoon) of fuel through plug hole, refit plug & try, if it fires it will show fuel problem up. Also, is the plug wet when you remove it after trying to start? If it's very wet, may just be badly flooded. If not wet, check for fuel filter & if it's blocked, check air filter etc, hope this helps.

Check air filter, fuel filter and carb jets...
Check exhaust for obstructions and your plug wires.