well I am at the 3rd stage of my tinkeriing around with my jets.


1st... I got my raptor brand new, added nerfs, bumper, and rear grab bar, and warmed it up , then measured top speed with gps and went 77 mph

2nd...added skids, pro design kit w/kn filter, ehs lid, put on a yoshi pipe w/headers and jetted w/dynojet kit at 146/148 with clip on 4th down, top speed 73mph

3rd...rejetted at 148/150 everything else the same, top speed 73 mph....74 mph downhill....lol



only difference between stock mph and piped mph top speeds are the GYT-R skids and my elka shocks....do they make that big of a difference?

all top speed runs were made on same trail and measured with gps

should I try to increase jet sizes again?

screws are set at 3 turns out on each side

it runs pretty good...no noticible popping or backfiring...

I really expected a bit more with this pipe, airbox stuff, increased jetting, etc...

when I race my buds 03 LE raptor which is bone stock, I can get him out of the hole and have a lead after 1st couple shifts...but after we both get in 5th...he catches up and passes me

[img]i/expressions/face-icon-small-blush.gif[/img]

kind of sad...don't ya think? he does weigh about 50 lbs less than me, and my bike does weigh more than his, so its bout 80 lb difference but still....


anyone out there got any words of wisdom for me? should I increase my jet sizes again? what size?

do those top speeds seem right with the mods I have?

 

You could be running lean or rich on top and either one could cause your bike to drop off on top. By adding the pipe and filter set up you should have gotten an good increae in HP over stock if your jetting is right and the little bit of extra weight added should'nt affect the top speed the way you explained it if nothing else changed. I would say your jetting is off; Try richening it up to see what affect it has and if it does'nt help go the other way. One thing I would do first is to try and get a good plug reading and take it from there. Trial and error is pretty much the only way unless you had it on a dyno to tune your jetting. Are you sure your GPS is reading accuratley and if so something is'nt quite right. Getting your jetting correct can be a pain but with the new addition of the pipe you should be able to tell a good amount of power incease over the stock setup! The stock bike of your buds should'nt be running you down. Good Luck, Slim

 

I'm assuming you still have the stock gearing. The mods you have described are intended for one purpose, really. Increasing bottom end torque, in order to improve handling in the woods, on tracks, and in cruising situations. If you are looking to improve top speed without any more mods, I suggest adding a tooth or two in the front, and/or adjusting the rear sprocket as well. The combination of a pipe and filter allow the engine to breath better and thus rev quicker. This will improve torque with the stock gearing and no major engine adjustments. The easiest ways to increase top speed are with tire size changes and sprocket changes. I am not surprised your top speed DEcreased, due to the nature of these mods. That is why you eat the stock raptor out of the hole, and then lose to him in the long run. As for your jetting, I think you are running lean for having a Yosh pipe. I run richer than that, and I have a full Big Gun with pro/flo and no lid. You're needle clip position sounds a notch low. Try raising that and increasing your jets. You could also throw the stock header back on and run the Yosh silencer. It will be considerably louder, but the smaller diameter head pipe might help increase top end. Realizing that I wouldn't want to do this myself, you probably won't either. Good luck. By the way, nice shocks. Like Slim said, trial and error. I was at Silver Lake for the Fourth, and rejetted my bike and adjusted the floats three times. It rips now. Just takes time.

 

if it is a bit lean, what is recommended for the next step?

raise clips 1 notch to 3rd position?

increase jets size? to what?

adjust fuel screws to 2 turns out?

should I try any of above in any particular order?

 

Did you try running it with the lid off? I don't think those EHS lids breath very well.

 

Pull your plug. What does it look like? Those are about the same jet settings i hads on mine with your combo but, i ran no airbox lid.

First check the plug, tell us what it looks like (color). Then try running it without the lid (like sixsixt suggests and, i bet you'll see a difference! Report on the plug though, you may be a little lean in the midrange. Most engine tuning problems start by incorrect jetting in the midrange (clip position) where you spend 90% of your time.

 

there is a pic of my plug im my pics page

I am really skeptical about no lid in the Louisiana woods cause of all the water/swamps I ride through.

but I will try....

 

If you try the clip position at the third down, you can bump the jets up to 150 155. Take your lid off as well. If you are running an outerwear, you should be fine as long as the airbox itself is still intact. Turn the fuel screws to 21/2 turns out. If they need adjustment after that, only adjust the left carb fuel screw. Try that. What elevation are you at?

I know that Louisiana is full of swamps, but I can't imagine riding a raptor in the swamps.

 

I don't think you should be trusting your GPS for max speed. In my experience they can throw some crazy numbers sometimes. (One time mine said I had gone 130 mph when I actually only went a max of 60.)

 

I dont actually ride in the swamps, but there is lots of water...crossing trails and such.

I am about 100 ft elevation

my gps has been pretty accurate when travelling in my truck[img]i/expressions/face-icon-small-wink.gif[/img]

thanks for the tips, I will give them a try, just thought it odd, that I lose topend on my pipe and jet and gained low/midrange

looks like I will be spending some more wrench time on it

dam I have too many other things to do[img]i/expressions/face-icon-small-sad.gif[/img]