Hello Everyone,

My Big Gun 'Quiet Core' exhaust just came in last night. I now need to purchase both the main and pilot jets, just as Paul at Big Gun suggested. I called my local Yamaha dealership yesterday and they told me that there were 2 types of main jets. Yamaha manufactures both a 'short' base and a 'long' base main jet. They were not sure which type of jet belongs in the Raptor. They only have the short base jet in stock. Does anyone know what type of main jet belongs in my machine without me pulling of the carbs? Also, once I have the jets installed, is it necessary for me to adjust the air/mixture screws? My guess would be yes, but any feedback on this would be greatly appreciated! I'm looking to install the exhaust system this weekend.

Thanks guys!!

IronBear

 

The Raptor requires the "Small Round" type of main jet. The jet has a slit on the top that requires a "flat head" screwdriver to take them in and out. The short base that your dealer is referring to should be the "small round".

When you are changing the mains, a half turn out on the air/fuel screws (counter-clockwise) should ward off a potentially lean idle circuit (assuming you don't have the problem now).

Remember, upon deceleration with no throttle applied, if the machine pops back thruogh the exhaust, you are clearly lean.

Please give a full report once installed and dialed in.

 

Gary,

Thank you for your response. I will be sure to give you guys a full report.

I have to ask everone's opinion on this. My friend has owned a Bombardier and he said that he installed the Big Gun 'Quiet Series' exhaust with the proper jetting said that he did not notice a difference with the new exhaust. Will I be dissapointed? I hope not. I trust everone's judgement on this forum. So please, give me some feedback.

Thank You,

IronBear

 

I think it really depends on the quad. It did wonders for my Rubicon but I hear it does nothing for a Honda 450.

BTW, the stock packing will go fast! I'm guessing about 100 miles and it was gone.

 

TexMud,

You sure you're talking about the Big Gun Quiet Series? This series is brand new and carries a two year warranty to keep the noise below 94dB. Maybe you're referring to the Race Series?

 

Ironbear,

I just did the big gun race and it is an improvement. I notice the power on the bottom end is much better. I am not sure on the quiet series, but I do like my big gun. I also really like the finish on mine.

I did the dyno jet kit and it helped out quite a bit, I did it a little richer than they say, I guess I like knowing it is a little on the rich side and better safe than sorry.

I am going duning tommorow and should know more after that.

Good luck
Paul

 

Yep I'm talking about the so called quiet series.