2005 Yamaha Raptor 350 wont start

[superchief]

I have a 2005 Yamaha Raptor 350 se i just recently replaced my cdi, coil, spark plug, pick up coil and ever since i replaced this stough i go to pull start the quad and all it wants to do is back fire i checked the timing the bike is in time idk tho i need help

[Ajmboy]

Is it all aftermarket stuff? If so, what is the brand?

* Removed your other thread as it is a duplicate of this one.

* Added year and manufacturer to your thread title as per forum guidelines.

[GEARHEAD01]

check the gap on the spark plug. the gap should be set to manufacturers spec. it co-insides with the timing of the engine.

[superchief]

well the cdi is a pro rev box the coil is stock from yamaha and the pick up coil is after market off ebay, dont remember the brand and the spark plug is a stock one too...... i have bought like 3 plugs for it but never checked the gap????????

[DirtDemon]

When you say you checked the timing, how did you do that if you can't get the engine to start? Did you mean the valve timing or the ignition timing? Although, you did not mention whether or not the it will start with the electric start. Does that work? Does it ever jerk the pull starter back out of your hand when it backfires? I assume you have spark if it is backfiring. Have you checked the flywheel timing key? If you take off the stator cover, you can look in and see if the key has sheared off. That would be a shame because that is like a $2 or $3 part, and that would mean you have wasted all that money on a whole new ignition. Have you checked the valve lash?

[superchief]

i checked the timing by lining up the T with the cam arrow and the head. the one bearing locked up so i took that off along with the gear so i have been pull starting it with my other quad.i have spark good compression and just rebuilt the carb. i pulled the flywheel to check that key it was fine. whats the valve lash???? o and on the crank there is an arrow and that lines up with the arrow on the case.

[superchief]

can some one help

[GEARHEAD01]

are you sure that is the right cdi box. i would put your factory one back on and try it. also i would check your manual and check your timing according to your book. also if your valve lash is too loose then your engine does not release the compression mase by the combustion of the fuel and air causing it to back fire. put your engine on TDC and check for the clearance between your valve stem and the rocker arm. set it according to your manual as well. These are some points for you to start at.

[superchief]

i put the old one back on and got no spark ??????????????????????wat is valve lash?

[GEARHEAD01]

valve lash is the space between the rocker arm and valve stem. you also could have recieved the wrong cdi or a faulty program in the cdi.

[superchief]

well that would suck if the cdi is faulty and i took the parking brake off and didnt put a block off plate on could that cause it to not start?

[superchief]

plus i just remembered that when im pullin it the carb is sucking in alot of air thru the airbox u can hear it also the exhaust gets warm

[DirtDemon]

Have you checked the vavles yet, if they are too tight, they don't close all the way.

[Raptor8]

could be a tight valve, too rich carb, or maybe even 180 degrees out on the cam. Time to buy a book. hard to diagnose without seeing it... sorry:aargh: