what I did to my WR 450 today - and smart guy jetting question!?
Posted April 17, 2008 - 07:30 PM
What I came from: stock pipe, opened air box, GYTR AIS removal with GYTR 165 main jet and needle and a 48 pilot. 2 turns out. All other items are stock including air filter with Belray. How it ran was very responsive and right on the money through the entire powerband. Small amount of bog when riding singltrack at 15mph or less. Ran good at all temperatures and humidity from 0 to 4000 altitude (ran better in the 80-100 temp than in 50-70 but still adequate). Always hard to start though.
What it is NOW: FMF PowerCore with PowerBomb and quiet core, UNI air filter with NO-TOIL oil and very open air box, 170 main, JD Red #5, 48 pilot, 40 leak jet, ran best with 1 turn out of my zipty. How it ran in 65 degrees at 200 altitude close to ocean. Starts very easy. good response through whole powerband if I am not twisting hard. If I yank the throttle hard which is how I always ride, the first 1/8 throttle is good response and then 1/4 through 3/4 is not consistant and seems to be blotchy and boggy and a little bit of popping. 3/4 to full is pretty much the same.
My original thoughts were to tune it to 80+ degrees cuz summer is here and I ride mostly between 2000 to 3000 altitude inland in the mountains, not by the ocean. I went with what I did because of what I thought from reading my JD jet directions and from Indy 450 and others. I know my riding condition is now different than it is going to be at the 60 degrees and 200 altititude but should I start with dropping the 170 main to 168 or 165. I thought that since I had a 165 already before opening up my exhaust that I could afford to do the 170 - guess not. Or should I change the eclip on my JD red to #4 position or move to the Blue #3 as seeming to be for all the winter riding?? Please advise on where and what I should do?? Thanks, Jason:confused:
Posted April 18, 2008 - 01:42 AM
Posted April 18, 2008 - 01:43 AM
Because you plan to ride at a higher alititude where the air becomes thinner you will need to go leaner on the jetting to compensate for that.
As you are having dramas between 1/4-3/4 throttle I would start with the needle moving it down a clip to # 4, then possibly # 3 if # 4 is not much of an improvement.
You might even need to go to a 162 or 160 main as well. I had the same deal when I added my GYTR race pipe, I went richer on the jetting from 165 to 170 and two days later had to go back to where it was, originally a 165. Finally I went to a 162 and that improved it further. Seemed weird to me but worked out great.
The small amount of bog when riding 15mph is probably caused your AP pump timing being slightly off.
Don't want to insult your intelligence but make sure you change just one thing at a time or it will be confusion city.
Posted April 18, 2008 - 09:25 AM
Posted April 18, 2008 - 12:40 PM
Do I change the needle next to 4th position or .........? Also, still want opinion on the AP timing. Did I adjust my screw out too much and am flooding my carb. I read on the AP 101 that it can make the bike boggy it is turned out too far, but dont know if that effect goes through the powerband. I know that I adjusted the AP about 3 turns out from where it was to get it to the specs on the JD jet kit directions!??
I need somemore opinions. thanks, Jason
Posted April 18, 2008 - 04:56 PM
If you take off the airbox boot from the carb and warm the bike up open the throttle as you would when riding and see if the squirt of fuel from the AP is clearing the carb slide or not, if it is not then the AP needs further adjustment.
Go out and get a 45 PJ then set up your pilot circuit as per the link below from Eddie the jetting man.
Then you can eliminate the PJ and pilot circuit from the equation - I would do this first as its the easiest to check.
If that doesn't improve things work, drop the needle to position 4.
Posted April 18, 2008 - 05:46 PM
I do agree that I need to do one thing at a time but that will be hard cuz my head is spinning and I want so bad to just twist and get it on.
I know what you mean, I'm laid up for 6 weeks after a knee operation so TT helps relieve the boredom and I learn stuff too!
Check out this thread below for AP timing mainly from Barton, some really great info.
Your best bet might be to get the bike on the dyno and let a respected tuning shop do the hard work?
http://www.thumperta...ing AP FCR carb
Posted April 18, 2008 - 07:01 PM
Posted April 18, 2008 - 09:45 PM
Posted April 19, 2008 - 11:24 AM
Posted April 19, 2008 - 01:11 PM
Posted April 19, 2008 - 02:04 PM
Posted April 19, 2008 - 08:41 PM
I hear you on needing the entire throttle capability and believe me - I use all of it. I am always WOT (wide open throttle) from slow to fast. I was just under the impression that with the yz cam you have starting issues and then a more touchy and sensitive low end closed to 1/8 throttle!?? I went up to Kennedy Meadows last year with my original settings (see first write up on this page) and went 22 miles and had to fill up again on gas. I think the guy behind me got sprays of gas on him everytime I hit the throttle (haha!) Beatiful country up there - might try to do it again this year before summer hits. This time I'll be tuned for it though!
Hope your knee gets better - when you can - start doing range of motion excersizes to increase blood flow. That will push out toxins and scar tissue and inrease spead of healing by bringing in more nutrients to your injured tissue. Eat good balanced meals and no heavy smoking and drinking as this has many adverse effects on healing.
As to someone putting my bike on a dyno - A respected tuning shop - maybe if I could find one. I go down to the dealers and ask their mechanics questions and find that they cant answer the questions I ask. Much better to ask guys with a passion for what they do than someone that just earnes a dollar for twisting a wrench. I find that it all trades though. I know there are good honest hardworking trustfull people out there but they are scarce - so as I stated I trust in people with a passion about what they have and do and that is a value in this web site. Happy healing. Jason
Posted April 20, 2008 - 06:58 PM
Posted April 23, 2008 - 03:19 PM
Ok, changed my stuff around for trial and error. 170 main, 45 pilot, #50 leak jet, blue needle at #3 from top, AP squirt cant hit the slide when turned in or out. Duration is dont know now, but was app. .8 seconds with the #40 leak jet. Its problably close. My timing adjustment is as recomended by JD jetting (I called and talked with them re my situation). That is 2.75 mm. When I turned the screw out 1 full turn from there it seemed to be a little better on response but still has hesitation.
HOW did it run - Not compleetely sure cuz I dont have a place to ride it around alot. It had ok bottom from 0 - 1/8, It had good hit from 1/8 to 1/4, It had ok 1/2 to 3/4 and full but seamed to flatten out and loose my power when WOT. Dont like that cuz thats the position I am usually in - I ride my bike like a 2strke. I am trying things on the rich side of things to see if that works better without hurting my engine. Any ideas??? Jason
Posted April 23, 2008 - 04:13 PM
Posted April 24, 2008 - 02:03 PM