Yamaha Discussions about Yamaha ATVs.

*Update #13 (not fixed) - ongoing throttle response problem with Raptor

Thread Tools
 
Search this Thread
 
  #11  
Old 03-09-2003, 12:20 PM
NotuRaptor2's Avatar
Pro Rider
Thread Starter
Join Date: Aug 2001
Posts: 783
Likes: 0
Received 0 Likes on 0 Posts
Default *Updated* - ongoing throttle response problem with Raptor

First off, thanks for the feedback.

More info:

Battery terminals tight
Right carb adjusted 3 turns out
Left carb adjusted 2.5 turns out
Put a fresh air filter on it.

Runs okay to about 1/2 throttle then start breaking up.

Spark plug is a dry black soot (not real thick or anything but definitely covering everything exposed inside the cylinder head)

I haven't adjusted the valves in about 40-50 hours. Any chance this is it? Doesn't seem like putting in a new plug would fix something like this but I have to admit I know a lot more about everything else except the internals of the engine.

It is currently about 40-50 degrees outside. I've never had a problem before riding in 80+ degree weather nor even in November at Hatfield McCoy riding in the mountains at about 20-30 degrees riding at around 3,000-6000 feet above sea level.

I am getting ready to put a new plug in it. I am sure it will run like a champ again for a few hours.

/NotuRaptor
 
  #12  
Old 03-09-2003, 12:38 PM
sixsixT's Avatar
Extreme Pro Rider
Join Date: May 2002
Posts: 3,286
Likes: 0
Received 1 Like on 1 Post
Default *Updated* - ongoing throttle response problem with Raptor

WOW!! 40 or 50 hours since you adjusted the valves.[img]i/expressions/face-icon-small-shocked.gif[/img]
 
  #13  
Old 03-09-2003, 12:51 PM
NotuRaptor2's Avatar
Pro Rider
Thread Starter
Join Date: Aug 2001
Posts: 783
Likes: 0
Received 0 Likes on 0 Posts
Default *Updated* - ongoing throttle response problem with Raptor

The good news is that a new spark plug didn't change a thing.

I am going to start looking at the things Gary mentioned.

/NotuRaptor
 
  #14  
Old 03-09-2003, 01:52 PM
wshrdskin's Avatar
Extreme Pro Rider
Join Date: Feb 2002
Posts: 4,156
Likes: 0
Received 0 Likes on 0 Posts
Default *Updated* - ongoing throttle response problem with Raptor

Dyno jet reccomends 4th clip from the top. If you want to lean it out 1 step on the needle, move the clip to the 3rd clip from top.

If your plug is a black soot you are running rich.

40-50 hours without a valve adjustment? Do a valve adjustment whether this is your problem or not. Although, as the engine warms up and if your valves are tight you will lose compression because the valves tighten as the engine warms, this will cause boggs and hesitations if the valves are not closing all the way.
 
  #15  
Old 03-09-2003, 04:14 PM
Ward660R's Avatar
Extreme Pro Rider
Join Date: Jan 2002
Posts: 4,104
Likes: 0
Received 0 Likes on 0 Posts
Default *Updated* - ongoing throttle response problem with Raptor

I am going to go with what Gary said, the cross over tube being kinked. I would think it would be a jetting problem but if you haven't touched it in a long time why would it just start getting more rich?



good luck
 
  #16  
Old 03-09-2003, 04:17 PM
wshrdskin's Avatar
Extreme Pro Rider
Join Date: Feb 2002
Posts: 4,156
Likes: 0
Received 0 Likes on 0 Posts
Default *Updated* - ongoing throttle response problem with Raptor

Temp change will fatten and lean fuel mixture.

Hotter=fatter
Colder=Leaner
 
  #17  
Old 03-09-2003, 04:29 PM
Ward660R's Avatar
Extreme Pro Rider
Join Date: Jan 2002
Posts: 4,104
Likes: 0
Received 0 Likes on 0 Posts
Default *Updated* - ongoing throttle response problem with Raptor

yeah but I mean he said its been jetted like this since 2001, why didn't it do it last winter?

Also I don't think it would have been so bad, from temp change, that it would only run at 1/10 throttle. Just my opinon though.
 
  #18  
Old 03-09-2003, 04:33 PM
wshrdskin's Avatar
Extreme Pro Rider
Join Date: Feb 2002
Posts: 4,156
Likes: 0
Received 0 Likes on 0 Posts
Default *Updated* - ongoing throttle response problem with Raptor

I agree. [img]i/expressions/face-icon-small-smile.gif[/img] Just putting out the info. [img]i/expressions/face-icon-small-wink.gif[/img]
 
  #19  
Old 03-09-2003, 05:27 PM
sixsixT's Avatar
Extreme Pro Rider
Join Date: May 2002
Posts: 3,286
Likes: 0
Received 1 Like on 1 Post
Default *Updated* - ongoing throttle response problem with Raptor

Do you think it would run fine for 2 or 3 hours if the cross over tube was kinked?
I still would put my money on your fuel filter/screen being restricted, or you have some crap floating around in your carbs.
Clean your fuel system and I bet it will run fine and ADJUST YOUR VALVES!!!
 
  #20  
Old 03-09-2003, 06:27 PM
NotuRaptor2's Avatar
Pro Rider
Thread Starter
Join Date: Aug 2001
Posts: 783
Likes: 0
Received 0 Likes on 0 Posts
Default *Updated* - ongoing throttle response problem with Raptor

Another update:

Took the fuel petcock out. Both screens looked fine. Fuel flows freely out both the regular and the reserve settings.

The carb cross over tube looks fine. No kinks.

Checked all the major electrical connections.

Planning to look at the valves next. Then...taking the carbs off and looking at them. This is frustrating. Used to reading about other people having problems and wondering why since mine always ran great no matter when and where I road.

I am running 148/150 jets and on the Dynojet recommended clip setting - I don't remember what that is though.

Is there or isn't there a reverse limiter on a 2001? By the way, I removed the emergency brake back in June 2001 too. Just disconnected the wires from the wire connector behind the radiator. I still have the clutch switch in place. I bought a left brake perch from a Kodiak since it has a single switch holder.

/NotuRaptor
 


Quick Reply: *Update #13 (not fixed) - ongoing throttle response problem with Raptor



All times are GMT -5. The time now is 03:26 AM.