2006 YZ450F jetting?

What does disconnecting the TPS do? And what are the pros / cons?

Originally Posted by aford541

Before I rode my bike I changed the jets to what Burned reccomended for a bike at sea lavel 48 / 170 with the fuel screw at 2 I ran ELF LMS fuel.

My bike still had an off idle bog and it still seemed lean, so I

1. raised the needle one.

2. wired the accelerator pump.

3. Installed both power now's.

4. disconnected the throttle position sensor.

Now the bike runs like a missle, its like you can't shift fast enough and the bike just keeps pulling, and never bogs.

Can you expaling where you learned about items 2 and 4?

Thanks

2. Steve From Just Performance told me about wiring the accellerator pump, it eliminates the need for the boyesen cover. Someone said Yamaha of troy does it on the 250f's they build. pm me your e-mail and I will take a picture of my 05 and e-mail it to you.

4. There is a dyno chart somewhere here on Thumper Talk that shows the improvement on the 03 through 05 yz's when you disconnect the TPS, It is my theorey that the TPS limits low RPM ignition advance so bad fuel does not make them detonate. Most of us use the good fuel and don't need it. I was going to plug it back in yesterday to see if it made any difference on my 06 but was freezing my a$$ off and opted not to.

I know people who have wired the accel pump and say it gives much better throttle response.

I appreciate all you guys getting the jetting done for me.

It's 25 degrees here and since I'm a homosexual I haven't even started my new bike.

I know people who have wired the accel pump and say it gives much better throttle response.

I appreciate all you guys getting the jetting done for me.

It's 25 degrees here and since I'm a homosexual I haven't even started my new bike.

Thats harsh, I'd start it regardless. :thumbsup:

cool, thanks guys this is what i wanted to see...

LOL! I lost my needle too. :p Fortunately the local shop had one of the aftermarket thumbscrew models in stock.

At sea level in Orlando at 50F I'm running a 45 pilot and a 170 main with the fuel screw at 2 1/4 turns out. Runs great.

I'm still dialing in the suspension to my liking and it's getting much better.

--KT--

OK, finally got some warm weather in "Iceland" (New Jersey), and I'm running a 48 pilot and a 170 main. The screw is out 1.75 and runs really crisp :thumbsup: , :thumbsup: A 45 on the pilot is good also, but I was afraid of lossing another screw :worthy:, so I opted for the next size. I went to the motorcycle show in NY City there were server people asking the same questions :eek: they did not know about thumpertalk. :bonk: Good riding to all!

This is interesting............please explain in detail what this does. How does it affect duration/squirt. How is this similar to what the QuickShot will accomplish - which is better for throttle response?

Anyone else have any feedback or test results on this mod?

I like this type of discussion............. :thumbsup:

This is interesting............please explain in detail what this does. How does it affect duration/squirt. How is this similar to what the QuickShot will accomplish - which is better for throttle response?

Anyone else have any feedback or test results on this mod?

I like this type of discussion............. :thumbsup:

Wiring the AP forces the fuel in instead of relying on the AP spring to push it in, In theorey it should squirt the fuel in at a higher rate thus shortening the duration.

I bought the Boyesen AP cover and it did not work with the AP wired, I don't know why but I returned it.

On the stand or on the track you crack the throttle and it barks, I was really impressed how the 05 YZ responded, the 06 is the same.

Try it, you can always remove the wire.

I have a new 06 yzf450 and had a very lean condition, popping, backfiring etc... at zero to 1/4 throttle opening.

Dealer stated they installed 45 pilots on all new 450s. They left the stock 42 in my bike. This is really no big deal, just need to do some minor tuning.

Location is Charlotte, NC 795 feet above sea level.

Weather has been in the range of 70 to 85 degrees and mostly dry air conditions.

To correct the lean condition:

1) Installed a Boyesen QuickShot.

2) Tried a 42, 45 pilot and ended up going **Update 04-25-06 installed 45 pilot, 48 was too rich in the 90' heat fuel screw at 2.***

3) Fuel screw 2~2.5 turns out (this is just my base line setting)

4) Needle raised (lowered clip one position) 5th clip position from top.

5) OEM - stock main jet 165

6) Leak Jet #50 (have a 45 on order and will update the post when I have the opportunity to test it)

7) Adjusted the accelerator pump timing screw .080 inch (Boyesen suggests .100) here is a good link for the proper steps to check the distance/timing. http://crfsonly.com/reviews/apc/apc.php

This produces instant crisp throttle response, no hesitation, bogging or popping and one kick starting. Also there is no popping or backfires on deceleration entering corners.

So far this bike is flawless, jetting is not a defect. This bike would run perfectly stock in southern FL 90 degrees 100% humidity. Suspension is super plush. Motor runs like an electric motor now, perfect.

I have an 06 450,Stock air filter,WB E-2,#165 main neenle jet 4th pos.,pilot#42,pilot air jet #100,pilot screw 2 1/8 out,starter jet#72,leak jet #55. :ride: I am in wash. st.about 1200 ft above sea level. It runs like a raped ape. I must have gotton lucky :crazy:

Are most of you guys just installing the wire on the AP pump like the pictures above?? I saw somewhere on here that you had to take the bottom AP cover off and do a few other things as well. I haven't done it yet. If all it takes is just the wire I will be all over it.

Sap

Not sure about the wiring of the AP (Accelerator Pump) timing adjuster. The AP rod is not fixed to the diaphragm. So the AP is relying on the spring to push fuel through the circuit when the throttle is opened, not the pulling of the rod. Correct me if I am off base.

I think everyone is missing the leak jet adjustment. The smaller the jet, the increase in pressure within the accelerator pump circuit to produce a stronger spray (Richer mixture off idle). It is hard to find the jets, but they are the same as the power jets on a 2002 rm250. Suzuki even gives the jet sizes in the parts Microfiche. The Suzuki part # is (JET, POWER (45) 13345-37F00).

I am having really good luck with: Boyesen QuickShot, 45 pilot, 50 leak jet, 165 main and stock needle fifth clip slot down.

This is great that we can all collaborate and share our tuning experiences from all over the Globe.

Not sure about the wiring of the AP (Accelerator Pump) timing adjuster. The AP rod is not fixed to the diaphragm. So the AP is relying on the spring to push fuel through the circuit when the throttle is opened, not the pulling of the rod. Correct me if I am off base.

I think everyone is missing the leak jet adjustment. The smaller the jet, the increase in pressure within the accelerator pump circuit to produce a stronger spray (Richer mixture off idle). It is hard to find the jets, but they are the same as the power jets on a 2002 rm250. Suzuki even gives the jet sizes in the parts Microfiche. The Suzuki part # is (JET, POWER (45) 13345-37F00).

I am having really good luck with: Boyesen QuickShot, 45 pilot, 50 leak jet, 165 main and stock needle fifth clip slot down.

This is great that we can all collaborate and share our tuning experiences from all over the Globe.

agreed and more amazing is all the differences for "the best setting" at the same general altitudes..... :crazy:

I will try the leak jet deal as I have a few of them...but I can not see a better than result from my 48/170 deal I have now... crisp throttle response, no bog, perfect....am I am a jetting nut....JD?

Live in Northern NJ. Stock Jetting was not working to good.

I backed out the air screw about a 1.25 turns, ran pretty good, but not right.

The screw must have been out pretty far, since is vibrated completely out in the field I was testing the bike in, nice. Bought after market needle to replace, much better to work with.

Went to a 45 pilot first, some difference, but not really noticeable. Then went to a 48, biggest difference was the air screw adjustment. The bike would actually run with it turned all the way in. It was a little over fifty degrees when I tested, it ran good, lots of good top end, but when I backed off the throttle, it popped big time. The biggest difference was in starting, much easier!

I went a 170 on the main, it got way to cold to test. Will test later this week again, suppose to go to fifties again, will let you guys know.

It's a fuel screw

Well that is not bad. Replying almost 10 years old post. :D

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now