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I am going through my motor on my 1987 Yamaha Phazer. Since I burned a piston, I am putting new Boyesen reeds in. The thing is, they come in two sets for each cylinder. I am unsure if I have to put both sets in each cylinder, or only one set. :dazed:

The install instructions are lame. They are for a MX bike and they say I need to lean out my main jet and richen the pilot jet. Any one have suggestions for jetting my Phizzer with these reeds?

Thanks O snow wizards... :D
 

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one up on the pilot and down 2 on the main. check the plugs and piston wash after a good pull in the coldest temps you plan on riddin'. my disclaimer: remember jetting is up to the guy reading the plug and checking the piston wash. in the 7-17f range that (1 up/2down) worked for us. I would be glad to help if I was near. the boyeson reeds are 2 stage so both petals go in. you have two cylinders to do.
 

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one up on the pilot and down 2 on the main. check the plugs and piston wash after a good pull in the coldest temps you plan on riddin'. my disclaimer: remember jetting is up to the guy reading the plug and checking the piston wash. in the 7-17f range that (1 up/2down) worked for us. I would be glad to help if I was near. the boyeson reeds are 2 stage so both petals go in. you have two cylinders to do.[/b]

The thing is when I got the sled, they had only ONE set in each valve cage, as is now. Also they went UP two sizes on the mains. I kept getting fouled plugs. Now I burned a piston going down to one size above stock on the mains. I don't know about the pilots. I will have to check them now too. Whoops! I am mistaken. One set X 4, two sets for each intake... :withstupid:

I also have an aftermarket pipe, not sure what brand it is either. Single two into one.
Here is a pic of my old piston...

http://www.snowmobileworld.com/forum/index...mp;#entry521127
 

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I put a set in my Mxz 700 and they are great, but not night and day different, just good throttle response. There should be 4 peddles w/ 2 or 4 holes in them and 4 smaller peddles. The smaller ones are the covers, basically , for the holes. Thats the "two" stage they're talking about. The small ones open first then the larger ones. The large ones go on first and the small ones go on over them.

The directions say you may need to go down 1-3 jet sizes on the mains. I experienced a lean condition when I went down two. I went back to stock and I'm ok now. So it depends on the sled. Look at the color after a run or 3 and go from there.

As for the piston check for air leaks. Did it burn down after installing the reeds? If you installed the large reeds w/ the holes in them and not the smaller covers you leaned it out beyond what can be explained!!!!! Please tell me you did not do that. :confused: If you did, do not even start the sled again untill you put on the small ones!!!

I do have a bit of a smokey idle so I may go down a size or half on the pilots. Pilots only come into play from idle to 1/4 throttle and play a small role at WOT. Don't jet unless you know what you're doing, please!


This is what the Boyesen site states.....

> Secondary Reed
(Top Reed)
The top reed is specially shaped, lightweight and resilient for crisp throttle response at partial throttle or low RPMs.
> Primary Reed
(Bottom Reed)
The bottom reed is thicker, stiffer and ported to provide stability, maximum flow and horsepower at high RPMs
 

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