This is going to be a full diagnostic for all the people who can't figure out why their bike isn't running great or at all. I'm sorry if i forget anything, but this should be all you need. I mean i am writing this while i sit at the nail salon waiting for my wife to get her nails done so i may forget something. Keep in mind that this is my way of doing things and some people do things differently. if you aren't trained to do this type of work you could do more harm than good. I'm not liable if you break something.
The ignition system is pretty basic on a blaster. You only need 4 things in order to run the motor, fuel, air, compression and spark. The stator plate controls the power and timing for the ignition system. Those wires run to the cdi. The cdi is the brain of your ignition system. It then sends power to the coil to fire the spark plug. The cdi also has a black wire with a white stripe. When that black and white wire comes into contact with ground, it stops the coil from getting power to fire the spark plug and the motor dies. This is really basic and there's a lot more to it as far as individual parts and functions go. Its good to learn how everything works to have a better chance at diagnosing the problems.
Every bike should be pressure tested as a form of regular maintenance. Once or twice a year, or after any motor work is done. While the motor is under pressure, spray it from top to bottom with soapy water. If you get bubbles, you have an air leak and need to fix it before you continue. Even after the bike passes a pressure test, you should warm the bike up to operating temperatures and then let the bike idle. YES, YOUR BLASTER SHOULD IDLE! if it doesn't, you need to tune it properly. While the bike is idling, spray the motor down with starting fluid, a small area at a time. Focusing mainly on your intake area. Spray around the carb boot, the reed cage, etc... If the rpm's increase, it means the starting fluid is getting into the motor and you have found an air leak. Fix the leak before you continue. I have found that the reed cage gaskets do a poor job of sealing and i have been using high heat rtv to seal my reed cage with great success.
The second thing you need to do is familiarize yourself with your bike. Go over the bike top to bottom. Look for any obvious damage. Is the air filter clean? Go over your entire wiring harness and check that everything is connected properly, look for any loose connectors or split wires, especially the black and white wire. Repair any damage. Unplug every wire connection, clean them with some steel wool and reconnect them with a little dielectric grease. I've found that 4 out of 5 times my bike has trouble starting, it's a bad connection somewhere.
If that doesn't fix the problem we have to dig a little deeper. Install a new spark plug and check for spark. If you have spark, go to the next paragraph. If your bike doesn't have spark, test the wiring coming out of your stator. If it doesn't pass, order replacement parts. If it passes, disconnect the wiring to the tors unit under the hood if you haven't already done a tors delete (which i would recommend). It is a 3 wire connector. Now recheck for spark. If you have spark, do a tors delete and you should be fine. If you still have no spark, i would suggest ordering a cdi and a coil. You can test them but in my opinion if they turn out to not be the problem, it's always good to have a backup on hand. Install them and there is no reason your bike shouldn't have spark at this point assuming your motor is grounding to the frame well. If you still have no spark, take it to someone with experience to get a professional opinion.
So you have spark. Try to start the bike. If it starts you're done. If it won't start, spray some starting fluid or mixed fuel down the intake and try again. If it fails to start, go to the next paragraph. IF THE BIKE STARTS, KILL IT IMMEDIATELY AND DO NOT REV IT UP! REVING THE BIKE LIKE THIS COULD BE CATASTROPHIC! You only want to verify if it will run given fuel. If it does, you now know that there is a fuel delivery issue. Drain your gas tank and clean or replace the petcock valve and refill with fresh fuel. Then pull off your carburetor and do a thorough cleaning. Test your needle valve and set your float hight to manufacturer specs. Make sure the overflow passages are clear and the jets are the proper size. Reassemble and reinstall the carb. Give it a minute be sure it fills with fuel and try to start the bike. There is no reason it shouldn't run at this point if the motor is in good condition. But...... if it doesn't, read the next paragraph.
So you have spark, and you have fuel... but the bike still won't run. Check that your reeds are sealing and that your intake and exhaust aren't clogged. If that is all good, I feel bad for you at this point. Pull off your gas tank and remove the spark plug. Do a compression test. Anything under 100psi has seen better days and either won't run good or won't run at all. My bike ran at 75psi after the piston ring sheared off, but wouldn't idle, now she purs like a pissed off lion. If the bike tests under 100psi you will most likely be needing a top end rebuild. This is costly, and before you do anything it is very very important that you figure out why it happened so that you can prevent it from happening again. Is the motor old enough to justify being worn out? If not... air leaks, running lean or severely rich, bad oil mix or broken oil injection, sinking the bike in a pond, using the wrong parts, etc... do not rebuild the motor unless you have at least a decent idea of why it happened and what you have to do to prevent it from happening again. If you can't figure it out, take the bike to someone who can to be checked out before you rebuild it.
Tuning is a pain to learn but well with it. If you don't want to learn to tune, get a fuel injected bike. I rebuilt my motor 3 times before i learned to tune. I could have saved a lot of money if i just learned sooner.
Blaster forum has a lot of great information and walk throughs.
Google and Youtube are your best friends when it comes to how to test everything and for specs. But feel free to ask if you have any questions. And if you live in the Philadelphia area i can do repairs and custom work.
Once you get running again make sure you keep up on your maintenance and always bring an emergency repair kit when you ride for on the trail repairs. Nothing is worse than being stuck on the trail to ruin your day of riding.
Good luck!
The ignition system is pretty basic on a blaster. You only need 4 things in order to run the motor, fuel, air, compression and spark. The stator plate controls the power and timing for the ignition system. Those wires run to the cdi. The cdi is the brain of your ignition system. It then sends power to the coil to fire the spark plug. The cdi also has a black wire with a white stripe. When that black and white wire comes into contact with ground, it stops the coil from getting power to fire the spark plug and the motor dies. This is really basic and there's a lot more to it as far as individual parts and functions go. Its good to learn how everything works to have a better chance at diagnosing the problems.
Every bike should be pressure tested as a form of regular maintenance. Once or twice a year, or after any motor work is done. While the motor is under pressure, spray it from top to bottom with soapy water. If you get bubbles, you have an air leak and need to fix it before you continue. Even after the bike passes a pressure test, you should warm the bike up to operating temperatures and then let the bike idle. YES, YOUR BLASTER SHOULD IDLE! if it doesn't, you need to tune it properly. While the bike is idling, spray the motor down with starting fluid, a small area at a time. Focusing mainly on your intake area. Spray around the carb boot, the reed cage, etc... If the rpm's increase, it means the starting fluid is getting into the motor and you have found an air leak. Fix the leak before you continue. I have found that the reed cage gaskets do a poor job of sealing and i have been using high heat rtv to seal my reed cage with great success.
The second thing you need to do is familiarize yourself with your bike. Go over the bike top to bottom. Look for any obvious damage. Is the air filter clean? Go over your entire wiring harness and check that everything is connected properly, look for any loose connectors or split wires, especially the black and white wire. Repair any damage. Unplug every wire connection, clean them with some steel wool and reconnect them with a little dielectric grease. I've found that 4 out of 5 times my bike has trouble starting, it's a bad connection somewhere.
If that doesn't fix the problem we have to dig a little deeper. Install a new spark plug and check for spark. If you have spark, go to the next paragraph. If your bike doesn't have spark, test the wiring coming out of your stator. If it doesn't pass, order replacement parts. If it passes, disconnect the wiring to the tors unit under the hood if you haven't already done a tors delete (which i would recommend). It is a 3 wire connector. Now recheck for spark. If you have spark, do a tors delete and you should be fine. If you still have no spark, i would suggest ordering a cdi and a coil. You can test them but in my opinion if they turn out to not be the problem, it's always good to have a backup on hand. Install them and there is no reason your bike shouldn't have spark at this point assuming your motor is grounding to the frame well. If you still have no spark, take it to someone with experience to get a professional opinion.
So you have spark. Try to start the bike. If it starts you're done. If it won't start, spray some starting fluid or mixed fuel down the intake and try again. If it fails to start, go to the next paragraph. IF THE BIKE STARTS, KILL IT IMMEDIATELY AND DO NOT REV IT UP! REVING THE BIKE LIKE THIS COULD BE CATASTROPHIC! You only want to verify if it will run given fuel. If it does, you now know that there is a fuel delivery issue. Drain your gas tank and clean or replace the petcock valve and refill with fresh fuel. Then pull off your carburetor and do a thorough cleaning. Test your needle valve and set your float hight to manufacturer specs. Make sure the overflow passages are clear and the jets are the proper size. Reassemble and reinstall the carb. Give it a minute be sure it fills with fuel and try to start the bike. There is no reason it shouldn't run at this point if the motor is in good condition. But...... if it doesn't, read the next paragraph.
So you have spark, and you have fuel... but the bike still won't run. Check that your reeds are sealing and that your intake and exhaust aren't clogged. If that is all good, I feel bad for you at this point. Pull off your gas tank and remove the spark plug. Do a compression test. Anything under 100psi has seen better days and either won't run good or won't run at all. My bike ran at 75psi after the piston ring sheared off, but wouldn't idle, now she purs like a pissed off lion. If the bike tests under 100psi you will most likely be needing a top end rebuild. This is costly, and before you do anything it is very very important that you figure out why it happened so that you can prevent it from happening again. Is the motor old enough to justify being worn out? If not... air leaks, running lean or severely rich, bad oil mix or broken oil injection, sinking the bike in a pond, using the wrong parts, etc... do not rebuild the motor unless you have at least a decent idea of why it happened and what you have to do to prevent it from happening again. If you can't figure it out, take the bike to someone who can to be checked out before you rebuild it.
Tuning is a pain to learn but well with it. If you don't want to learn to tune, get a fuel injected bike. I rebuilt my motor 3 times before i learned to tune. I could have saved a lot of money if i just learned sooner.
Blaster forum has a lot of great information and walk throughs.
Google and Youtube are your best friends when it comes to how to test everything and for specs. But feel free to ask if you have any questions. And if you live in the Philadelphia area i can do repairs and custom work.
Once you get running again make sure you keep up on your maintenance and always bring an emergency repair kit when you ride for on the trail repairs. Nothing is worse than being stuck on the trail to ruin your day of riding.
Good luck!
