how to remove spark plug 99 yz400f

12 replies to this topic
  • birchbark1

Posted April 06, 2007 - 11:00 AM


I just bought a 1999 yz400f and can't seem to get it started, it seems to have good compression and getting fuel, but I can't get the spark plug out to check for spark, I was trying to get it using a deep socket but I still can't reach it, is there some trick to it?

  • jayh300

Posted April 06, 2007 - 11:06 AM


deep socket and a swivel on my 99 400. the only way i ever get to mine is with the tank and seat off.
have you learned the starting drill yet ?????
keep you hand off the throttle when starting !!!!!!
put it on the master cyl.

  • birchbark1

Posted April 06, 2007 - 11:58 AM


ok, I followed the starting proceedure before removing the plug and got her started up, thanks for advice, now I have a problem with the clutch, when I pull the clutch lever in, I can see the lever moving on the tranny about an inch, but it's still not disengaging it, there doesn't look to be any more adjustment on the bar lever, any idea's on this one?

  • jayh300

Posted April 06, 2007 - 12:17 PM


have not had any clutch issues. some clutch cables have an adjustment in the cable itself also, but since i have not had any probs there not sure if the 400 does. is there a lot of play in the cable where it goes on to the lever ??? might look the length of the cable and see if there is a nut anywhere on it.
will look when i get home tonight and post.

  • birchbark1

Posted April 06, 2007 - 12:54 PM


ok, I got the clutch fixed up, and finally got to go for a ride, it been a few years since I had my last bike, the power of this thing sure is impressive, just can't wait for all the snow to disappear to really hot the trails, thanks for the posts

  • jayh300

Posted April 06, 2007 - 01:13 PM


cool... a few things to watch out for.
those bikes do not like to be rode slow. they will overheat quick. they need airflow across the radiators. i would check/change all fluids. get a manual, the maint. is was different from most other bikes.
make sure your coolant is up to spec. don't freak out when the header glows red, its normal. if you have any other questions, post away. there are some great guys here with tons of knowledge.
once you get to ride it alittle and figure out what it needs, look in the top of this forumn under the "sticky" mods and faq's. yeah the power of it is pretty cool. mine will wheelie in any gear at any speed that i have found.
see ya

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  • tammie

Posted April 06, 2007 - 04:45 PM


hi there welcome to the yz400 club....just a tip check the throttle cables at the attachment on the carb(remove the black cover) mine have frayed there twice over the last 4 years .....i don't knwo if its just my bike but i think ive heard others say that has happened you don't wnat to snap a throttle cable.....

  • tags

Posted April 06, 2007 - 05:46 PM


I got a 98 and man the control snap is awesome, wheeeeelieeee in what ever gear at any speed, high maintenance keep the oil changed often. I got mine 2nd hand and the original owner didn't change the oil enough and threw a gear through the case, the guy I got it from had to dish out $1600.00 Can. 2 weeks after purchase and then went street and I got it after case was AL welded and gearing replaced, so far (3ed year) not a problem. I rode my buddies 250cr, big weight difference, but I love the power control with the 4-Stroke, Not a common bike, but funnnnnn! Like you I am waiting for the ice and warm weather I am in Nova Scotia, and waiting. Tomorrow -3 and 10-15 cm of snow!!!!

  • 1rkcooper

Posted April 07, 2007 - 07:49 AM


where are you in BC?
Here is a link to the starting procedures, one is cold start, one is hot start procedures.
Be sure to check out the common threads sticky at the top of the YZ forum page it is full of info.

Have fun

  • birchbark1

Posted April 07, 2007 - 08:01 AM


I live in Elkford, it's a small town in south east BC, not far from the Aberta border, what about yourself, where do you live? Thanks for the starting procedure, since the bike is new to me, I'm sure it will take a bit until I get it down to an art.:bonk:

  • buzzgrizz

Posted April 07, 2007 - 10:30 AM


Tank off, swivel deep socket and a swivel extension help too.

  • 1rkcooper

Posted April 07, 2007 - 11:50 AM


Just East of Vernon. Enjoy the new ride.

  • roguetek

Posted May 04, 2009 - 09:03 PM


I am having the same problem with my clutch. What was the fix?


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