07-08 WR450, main air jet???

Anybody know what the stock main air jet is on the 07-08 WR450? It’s built into the carb. The GYTR AIS kit comes with a 110 Main air jet, which threads in line with the stock one.

I’m installing a JD jet kit and it makes no mention of the main air jet. Which is strange because if you are putting his jets on a bike that already had the AIS kit you would end up leaving the 110 in there, but if you do the JD kit on a stock carb, you’ll be using the built in main air jet.

So I was just wondering about you guys running the JD kit, if you have the 110 main air jet installed or not? Flip a coin? :confused:

Anybody know what the stock main air jet is on the 07-08 WR450? It’s built into the carb. The GYTR AIS kit comes with a 110 Main air jet, which threads in line with the stock one.

I’m installing a JD jet kit and it makes no mention of the main air jet. Which is strange because if you are putting his jets on a bike that already had the AIS kit you would end up leaving the 110 in there, but if you do the JD kit on a stock carb, you’ll be using the built in main air jet.

So I was just wondering about you guys running the JD kit, if you have the 110 main air jet installed or not? Flip a coin? :confused:

I'm almost certain that there is NO main air jet in the stock config, it's just a hole :excuseme:

I'm almost certain that there is NO main air jet in the stock config, it's just a hole :confused:

its buired in there 40mm deep. or at least that is what the factory pro HDJ kit says. so I think its in there.

www.factorypro.com/Prod_Pages/prodcy45.html

"Where's my main air jet and what do I do with that drill bit and tap that came in my Factory Pro HDJ kit for my Keihin FCR carb?

First step is to eliminate the fixed main air jet restriction.

It's about 40mm down the MAJ hole (left picture).

Set your 3mm drill so that it has 45mm to 46mm of drill bit exposed from your drill chuck.

(see right picture)

Remove the stock emulsion tube (that's what the main jet screws into) so that you can clean out the carb well. By only having 45mm to 46mm of the drill bit exposed, it prevents you from drilling too far.

Then, use the supplied tap from our HDJ carb kit, thread the Main Air Jet (aka "MAJ") hole.

You only need to go far enough to be able to thread in the new replaceable jet that we supply.

Clean the hole, of course.

After it's clean, complete the MAJ Modification by installing the supplied Main Air Jet and installing the new Factory Pro HDJ Emulsion Tube.

NOTE!!!

If you aren't confident in your ability or in your understanding of what you are trying to accomplish - no worry - Call us up or talk to someone locally who has more experience in these matters.

If you are still not sure, see if there's a Factory Pro Tuning Center locally or visit your favorite local dealership or shop and get some help there -

We all have to learn, and usually having an experienced person around makes everything "easy".

This modification is something similar to what we've done in many different carb types over the years, though it might be new to some who haven't used our "1.7-RK" carb kits before.

"

soooooo...

The final word was that with the jd kit, you wouldn't use the 110 main air jet supplied in the GYTR AIS kit. and the built in restriction is about a 200.

soooooo...

The final word was that with the jd kit, you wouldn't use the 110 main air jet supplied in the GYTR AIS kit. and the built in restriction is about a 200.

The GYTR AIS removal instructions say to "install main air jet in tapped open hole in the carburetor bell" That makes it sound like there wasn't a "jet" in there to begin with. I had a shop do all of the jetting for me. Installed the JDJetting kit and also the 110 main air jet that came with the AIS kit. The bike has been running great.

The GYTR AIS removal instructions say to "install main air jet in tapped open hole in the carburetor bell" That makes it sound like there wasn't a "jet" in there to begin with. I had a shop do all of the jetting for me. Installed the JDJetting kit and also the 110 main air jet that came with the AIS kit. The bike has been running great.

that is why I emailed JD and he said not to use the 110 main air jet. but he also said it would have little effect if installed. :confused:

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