alex456123
Well-Known Member
Alex456123’s FAQ guide to motor, transmission, electrical, Intake, and exhaust
1. Question: “I lost spark and don’t know what to do!”
Answer: first replace your spark plug, if that doesn’t work, test your coil and stator. If that is all within spec then test the CDI. (The only way to test the CDI is to put it on a running compatible year warrior)
2. question: “why does my quad shut down after warming up?” or “my quad is hard to start warm”
Answer: this is most likely your stator or coil. Test and replace as necessary if out of spec.
3. question: “my shifter is super sloppy. How do I fix it?”
Answer: replace your shifter with any year YZ250 shifter.
4. question: “what kind of motor oil should I use?”
Answer: any four stroke wet clutch approved oil. It is all personal prefrance.
5. question: “my quad seems to shift out of gear in high gears. How do I fix it?”
Answer: your clutch could be going, you need to adjust your clutch cable, or you need to adjust your reverse linkage. You do this by adjusting the tie rod linkage looking thing behind the lever.
6. question: “ my quad shuts down when I go through water. How do I fix it?”
Answer: dielectric grease all connectors. Then do a splash test. (Splash it with water while running at connectors to make sure they are sealed)
7. question: “why is my quad not revving past idle?”
If you have not already, you need to cut and bypass the parking brake switches.
8. question: “my exhaust studs broke off how do I fix it?”
Answer: get them drilled out and replace with M8-1.25 studs. Then they shouldn't ever break again.
9. question: “how do I adjust the idle?”
Answer: the idle screw on the left bottom of the carb there is a thumb screw. Turn it t the right to raise the idle, turn it to the left to lower it.
10. question: “my header glows red. Is this a problem?”
Answer: yes you are running too lean and need to go up a jet size.
11. question: “I blew out half my case from my chain breaking! How do I fix it?!?!?!”
Answer: you should have had a case saver be duneracerweston, but JB weld in the putty form works well. (JB stick) ( you should acid wash the area first before you apply the jb weld.)
12. question: “where do I put the extra steel in my clutch pack?”
Answer: next to any other steel in the middle of the clutch pack.
link:http://www.yfm350.com/forums/showthread.php?t=15097
13. question: “my starter doesn’t work! What the hell?!?”
Answer: your solenoid or your main fuse is probley bad. Check and test both. using a test light, probe the wire/lug at the starter itself with the starter button depressed. If it lights you have current to the starter, and the starter is the likely problem. If you don't have power at the starter, use a screw driver to jump the terminals on the solenoid (under left rear fender). If engine turns over, solenoid probable cause.
14. question: “ how hot are these quads supposed to run?!?!”
Answer: pretty damn hot. to help cool it and reduce engine temp, an oil cooler is the best addition you can make. link:http://www.yfm350.com/forums/showthread.php?t=15037
15. question: “where should I get parts?”
Answer: ebay, rocky mountain atv, ect.
16. question: “how do I do gearing?”
Answer: going up in tooth count on the front sprocket gives more TOP speed, but will accelerate slower. Going down in tooth size gives faster acceleration, less top speed. The rear sprocket works opposite ( more teeth, more torque, less teeth more top speed).
17. question: “when should I replace my timing chain?”
Answer: when your tensioner is all the way out. Check by first removing the spring from the tensioner then removing the tensioner. If you cannot move the plunger out anymore, it is maxed out, and you should replace the chain.
18. question: “why do my valves tick even when adjusted?”
Answer: warrior heads are notorious for being noisy. As long as its not like a knock and they are in spec don’t worry about it.
19. question: “why does my warrior smoke when I start it, but then stop?”
Answer: your valve seals are going bad.
20. question: “my quad backfires through the exhaust. Is this a problem?”
Answer: it is running rich and needs the jet down a size.
21. Question: "my starter works but it doesn't turn over?"
Answer: you need a new starter clutch.
1. Question: “I lost spark and don’t know what to do!”
Answer: first replace your spark plug, if that doesn’t work, test your coil and stator. If that is all within spec then test the CDI. (The only way to test the CDI is to put it on a running compatible year warrior)
2. question: “why does my quad shut down after warming up?” or “my quad is hard to start warm”
Answer: this is most likely your stator or coil. Test and replace as necessary if out of spec.
3. question: “my shifter is super sloppy. How do I fix it?”
Answer: replace your shifter with any year YZ250 shifter.
4. question: “what kind of motor oil should I use?”
Answer: any four stroke wet clutch approved oil. It is all personal prefrance.
5. question: “my quad seems to shift out of gear in high gears. How do I fix it?”
Answer: your clutch could be going, you need to adjust your clutch cable, or you need to adjust your reverse linkage. You do this by adjusting the tie rod linkage looking thing behind the lever.
6. question: “ my quad shuts down when I go through water. How do I fix it?”
Answer: dielectric grease all connectors. Then do a splash test. (Splash it with water while running at connectors to make sure they are sealed)
7. question: “why is my quad not revving past idle?”
If you have not already, you need to cut and bypass the parking brake switches.
8. question: “my exhaust studs broke off how do I fix it?”
Answer: get them drilled out and replace with M8-1.25 studs. Then they shouldn't ever break again.
9. question: “how do I adjust the idle?”
Answer: the idle screw on the left bottom of the carb there is a thumb screw. Turn it t the right to raise the idle, turn it to the left to lower it.
10. question: “my header glows red. Is this a problem?”
Answer: yes you are running too lean and need to go up a jet size.
11. question: “I blew out half my case from my chain breaking! How do I fix it?!?!?!”
Answer: you should have had a case saver be duneracerweston, but JB weld in the putty form works well. (JB stick) ( you should acid wash the area first before you apply the jb weld.)
12. question: “where do I put the extra steel in my clutch pack?”
Answer: next to any other steel in the middle of the clutch pack.
link:http://www.yfm350.com/forums/showthread.php?t=15097
13. question: “my starter doesn’t work! What the hell?!?”
Answer: your solenoid or your main fuse is probley bad. Check and test both. using a test light, probe the wire/lug at the starter itself with the starter button depressed. If it lights you have current to the starter, and the starter is the likely problem. If you don't have power at the starter, use a screw driver to jump the terminals on the solenoid (under left rear fender). If engine turns over, solenoid probable cause.
14. question: “ how hot are these quads supposed to run?!?!”
Answer: pretty damn hot. to help cool it and reduce engine temp, an oil cooler is the best addition you can make. link:http://www.yfm350.com/forums/showthread.php?t=15037
15. question: “where should I get parts?”
Answer: ebay, rocky mountain atv, ect.
16. question: “how do I do gearing?”
Answer: going up in tooth count on the front sprocket gives more TOP speed, but will accelerate slower. Going down in tooth size gives faster acceleration, less top speed. The rear sprocket works opposite ( more teeth, more torque, less teeth more top speed).
17. question: “when should I replace my timing chain?”
Answer: when your tensioner is all the way out. Check by first removing the spring from the tensioner then removing the tensioner. If you cannot move the plunger out anymore, it is maxed out, and you should replace the chain.
18. question: “why do my valves tick even when adjusted?”
Answer: warrior heads are notorious for being noisy. As long as its not like a knock and they are in spec don’t worry about it.
19. question: “why does my warrior smoke when I start it, but then stop?”
Answer: your valve seals are going bad.
20. question: “my quad backfires through the exhaust. Is this a problem?”
Answer: it is running rich and needs the jet down a size.
21. Question: "my starter works but it doesn't turn over?"
Answer: you need a new starter clutch.
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