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daddio
08-08-2005, 11:44 AM
here is the deal........ My yfz has been running great for a year now. the jetting is spot on. at the last race it ran great during the heat races, but during the main event, it started to sputter, like it was running out of fuel. The next day I checked all the wires and connections and found that one of the wires going to the "yamaha update" resistor broke off. could this have damaged my stator?
I switched it back to using only the stock resistor.
I also checked the fuel cap, petcock and vent. Dissasembled the carb........ very clean. valve clearance is in spec. changed the spark plug.
It runs like the rev limiter is comming on way too early.
I'm out of Ideas................. please help
metalmellinium
08-14-2005, 11:42 PM
What are your mods? Also how full was your gas at the race? If it is too low it will cut out like that. I always run almost full and reserve turned on.
daddio
08-15-2005, 06:42 AM
Originally posted by metalmellinium
What are your mods? Also how full was your gas at the race? If it is too low it will cut out like that. I always run almost full and reserve turned on.
All I've done is add a sparks pipe and re-jetted. 170m 48p 2-turns air, sparks needle clip 4.
I know it can't be the jetting, b/c it's been running great for 1-1/2 years, in all sorts of weather.
BTW. I had 3/4 tank of gas, and I checked the gas vent and petcock.
metalmellinium
08-15-2005, 10:48 PM
Hmm i have no clue then, maybe its your cdi
daddio
08-16-2005, 06:52 AM
I swapped cdi boxes and the coil with ones I knew worked. No change. I'm thinking stator. I got a new one on the way. I hope it works.
daddio
08-23-2005, 05:14 PM
Update.............I put a new stator in and it's all better now.:D :D :D
metalmellinium
08-23-2005, 07:35 PM
Awesome, glad you got it figured out. I wonder how it went bad tho
daddio
08-24-2005, 06:51 AM
Originally posted by metalmellinium
Awesome, glad you got it figured out. I wonder how it went bad tho
One of the wires broke off my ceramic resistor (part of the Yamaha update kit), and I'm not sure how long I was riding without it hooked up, and I'm pretty sure that caused the stator to go bad.
BTW........ I suggest anyone else running the yamaha electrical update kit, to put a big gob of rtv sealand on the wires where they go into the ceramic block, to isolate them from any vibration. I found out too late.
Shocka400ex
08-24-2005, 08:20 AM
This is very common. i don't know how many guys including myself went through the same chit. Replaced the stator and your good to go!