Return of the Bog Monster!!!

9 replies to this topic
  • clark4131

Posted July 02, 2005 - 10:45 PM


So now that we're in the 90's on a regular basis, I decided to drop my pilot from a 48 to a 45. I was running a 165 Main, JD Red #5, 1.25 on the screw, Boyesen Quickshot, tuned squirt, etc and all was well except for the slightest bog when wicking open the throttle from idle. With the 45 in there, the bog is now GINORMOUS :) , which got me to thinking. Perhaps I've been dealing with a lean pilot circuit all along. I didn't have any real decel popping, just the occasional pop here and there. Anyway, I'm going to put in a 50 Pilot and see what my results are. Any thoughts on the matter?...SC

  • Dan_Lorenze

Posted July 03, 2005 - 06:56 AM


Steve, I dunno.... I think that the 48 is a good pilot for you. If anything your main should be at least a 168, I've been runnin the 170 with great results. I would stay with the 48.. Also, I would be careful adjusting the squirt duration on the ap, they come adjusted pretty well.. Just my opinion...


Posted July 03, 2005 - 07:59 AM


I havent had to adjust the AP on any 05 WR's. Just the quickshot, 48PJ/170MJ and an 04 needle. Havent messed with the JD stuff. The bog is most likely due to a lean condition. Is your airbox opened up? Where are you on the fuel screw?

  • clark4131

Posted July 03, 2005 - 09:05 AM


I didn't do a whole lot of adjusting to the AP, just fine tuned it according to the manual using a 3mm hex wrench under the slide to give the proper height. Because of the results, I obviously need to go back to at least a 48 pilot, and I'll richen up the main as well.

I had the Barnum's Pro Airbox kit installed and I popped out the knock-outs on the right side of the airbox as well, so I have a lot of air flow. That coupled with the full FMF exhaust would tend to make me think I've really leaned things out. I have an unmodified replacement filter cover on there now just to see what the difference is when I run it.

Are you guys with '05's finding that the Zip-Ty fuel screw seems to have little to no effect when turned all the way in? I can only effect the idle by turning it all the way out which causes the idle to stumble a bit. I hear all these guys saying that it has a noticeable effect, buy I have yet to see it regardless of the jetting configuration I'm running.

One of the local dealers, in Quincy, says he sets up the '05's with the free mods and just a change to the pilot by bumping it to a 50. With that setup, his bikes run great with no bog or anything, so he says. It's worth a shot I guess. BTW, what is the proper '04 needle to use for the 4500' elevation range? Yamaha parts lists about 8 different needles, so I'm not sure which one would be the proper choice. Thanks for the help...SC


Posted July 04, 2005 - 07:49 AM


If you get no that sort of response from the fuel screw, you are too lean on the pilot. Bump to a 50 and see how that works. Turn the screw in all the way then back it out up to 3 turns. If at 3 turns out you still get no response go still bigger on the pilot.

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  • waterdog3

Posted July 04, 2005 - 03:20 PM


i am having the same problem. no responce to the air/fuel screw until i am 4 turns out, and there is a noticeable bog. 04WR450 all the free mods, GYT-R full exhaust,Alt 300'-900', 95-105,very humid,160main,48pilot,40leak.

  • clark4131

Posted July 04, 2005 - 03:29 PM


I won't be able to work on it until Wednesday...I'm at work for 72 hours straight. I'm going to bump up to a 50 pilot and a 168 main and see what happens. I've also got a wide open airbox and I'm running a 100 PAJ. After that, I'll check my bog and play with 1/4 turns on the AP to fine tune it. I may go to the #4 on the JD Red needle, as I'm currently #5. Then, of course, there's the fuel screw to play with as well. I'm going to document each change and it's effect as I go, so I know what's happening. I thought I had this thing dialed, but I guess I was wrong. Oh well, at least it gives me something to do...SC

  • clark4131

Posted July 05, 2005 - 10:56 AM


I think I figured it out! I have a low end bog and high end cut out that mimics hitting the rev limiter. My settings were a 48 Pilot/165 Main. If I go to a 50 Pilot and 168/170 Main with all my mods, I should cure my problem, theoretically. I got to thinking that during my last ride I went from around 4700' to a little over 7000' feet. As I climbed, the bike begain running much better...DUH!!!! :D I was obviously too lean. I've been running too lean on my pilot due to all the mods. I have a WIDE open airbox, a Powernow, a full FMF system and a #100 PAJ. Do you think my pilot circuit might need a little more fuel for all the breathing the bike is doing?

So, I'm picking up a 50 pilot today and I've got mains all the way up to a 178. I put in a brand new iridium NGK and the carb is clean enough to eat my oatmeal out of. The new jets will goes in tomorrow morning, so we shall see my friends. The light went on this time, and I was home. I think I've had a carburating epiphany :) :) ...SC

  • clark4131

Posted July 05, 2005 - 08:39 PM


Well, I couldn't wait until tomorrow 'cuz the wife is coming home with the kids and I'd be in the dog house if I spent the day tinkering. So I upped my pilot to a #50 and my Main to a #168. I dropped my Leak back down to a #35 from a #40. The bog definitely improved, but it still is not gone. My idle is also spot on. All this leads me to believe that it's got to be my AP timing. So I guess I'm gonna have to start playing with it 1/4 turn at a time. I think I need to delay it a bit to make sure it's not hitting the slide. With the #35 Leak jet, it has to be a long enough duration I would think. In any event, the quest goes on...SC

  • GrizzlyFlatter

Posted July 05, 2005 - 09:48 PM


Are you guys still running AIS stuff?Or did you plug that off?Trying to get some help for a friend with an 05 WR450f


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