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What are these jets that came with my 06 WR in Canada?

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I recently picked up a new 06 WR in Canada, and the dealer gave me some jets in a bag with the owners manual. I'm not even sure which type of jets they are, or why they were included?

Here's what I know:

Needle: GDERM

Big jet?: #40

Little jet?: #125

Little jet?: #95

The # looks more like a star or K.

The owners manual makes no mention of them. What are they for?

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The little jets are probably main jets.

The large jet is most likely a pilot jet.

Read up on your service manual (Primarily pages 7-1 to 7-10 for information on how to jet your bike.

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Do these bikes normally come with a little bag of jets? It just seems very strange.

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Do these bikes normally come with a little bag of jets? It just seems very strange.

Yes. Not every bike is going to be jetted the same. They provide any jets if you need to make any adjustments.

Again, read your manual, the pages I outlines, and it will all be clear.

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Ok, I read those pages. They vaguely tell you how one might adjust the carb. Nowhere did it say something like "We've included some jets with your bike. Go ahead and install all of them because we've determined that is the right combination for your area."

Or anything like that. That's just why I'm confused. The carb obviously has jets in it. Why did they include a bag of new jets? Am I just supposed to swap them in? Are they predetermined to work?

If I have really dive into this, reading plugs, and adjusting as necessary, etc... why include a bag of random jets with the bike?

Still working on the pic, got host it, etc.

BTW, I'm not a complete newb to engines. I know how to program fuel injection from scratch. Just trying to figure out why the bike came with a bag of jets.

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Well, a higher altitude will mean that you will need to lean out your mixture. Or if you go lower in altitude, you will need to rich out your mixture.

That is why the jets are included, incase you change altitude and need to rejet. Not saying that these are the jets that you use, but it may be.

IMHO, I think it's just a waste of money, but better than nothing.

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Since not everyone has the same climate, the bikes in different places need to be jetted differently. All the bikes come with the same jets installed. They normally come with a different size pilot, and main jets that are a little bigger and a little smaller than what is in it. They also come with a different needed. You will have to figure out what jetting is ideal for your elevation and climate. You will have to rejet as the climate changes (as temperature changes or humidity changes) or if you have a large change in elevation. You will most likely have to buy more jets than what is given depending on your location. For me, once I figure out what jetting is best, I only need to change the main jet as it warms up for summer, and then change it back in the fall as it gets colder. And of course I have to adjust the fuel screw as needed.

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Ok, so I think that answers my question. No, I'm not just supposed to throw the new jets in there and assume it's right. Now, is it safe to drive around for now using what came in the bike? Do they make it really safe? Or is it possibly too lean?

I'm used to tuning fuel injection on turbocharged cars. The A/F is super important, I run around 11:1 to prevent detonation, on a 9.6:1 compression ratio running 10-12psi of boost. If I go lean, 12:1 is probably ok, but if I hit 13:1... the engine will probably instantly blow up from detonation.

Is that the case with these bikes? Will they detonate and burn a piston if they're a little lean? Or they'll just misfire and lose power?

I have a wideband O2 for the car, I guess it might be worthwhile making an adaptor to use it on the bike.

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I'm not sure what comes in the WR stock, but my guess is that it is pretty cold in Ontario right now, so odds are it is too lean to ride right now. I would say to be safe throw in the biggest main you have and turn your gas screw out a little, then see how it runs. If it is popping and spitting flames then it is too lean and you will have to go bigger on probably the pilot and the main. It is better to be too rich than too lean.

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Ok, so I think that answers my question. No, I'm not just supposed to throw the new jets in there and assume it's right. Now, is it safe to drive around for now using what came in the bike? Do they make it really safe? Or is it possibly too lean?

I'm used to tuning fuel injection on turbocharged cars. The A/F is super important, I run around 11:1 to prevent detonation, on a 9.6:1 compression ratio running 10-12psi of boost. If I go lean, 12:1 is probably ok, but if I hit 13:1... the engine will probably instantly blow up from detonation.

Is that the case with these bikes? Will they detonate and burn a piston if they're a little lean? Or they'll just misfire and lose power?

I have a wideband O2 for the car, I guess it might be worthwhile making an adaptor to use it on the bike.

It is always a rule of thumb that whatever is in the bike is not safe (even if buying used unless the guy REALLY knew what he was talking about)

Read over in the manual on procedures on how to jet the bike. You can also read up here:

http://www.thumperfaq.com/jetting.htm

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I picked my 06 up in London Ontario and they told me the spare set was the set up for ice racing.

who knows if that's the truth

The AIS removal kit comes with an ajustable needle wich is nice

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Do all the free mods to your WR first (see www.thumperfaq.com), then put it on a dyno machine with an exhaust gas analyzer (EGA) and the graph will tell you exactly what your mixture looks like and which circuit needs adjustment.

All you Canadians with your cold weather, the stock jetting on your WRs are probably way lean right now in the Winter. Jet it rich to start with, it may run sluggish but it will be safer. Lean out your jetting until it becomes slightly too lean (detonation, popping, backfire, etc.) then go back up to the rich side about 1 or 2 jet sizes and you'll be right in the ball park. Of course, in the Summer when it gets hotter, you'll have to lean it out 1 or 2 jet sizes too. At that point, you'll know in the Summer to run this set of jets and in the Winter run this set of jets... You get the idea...

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I picked my 06 up in London Ontario and they told me the spare set was the set up for ice racing.

who knows if that's the truth

The AIS removal kit comes with an ajustable needle wich is nice

It could be for any type of riding, as long as the temperature comes down low enough to make the mixture leaner.

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