Is that the K&N in the stock air box? It sounds like it only does it when the bike is cold? Did this start right after you did the exhaust and filter? Never did it before? If you're doing a lot of short trips where the bike never really gets warmed up It can mess things up. It might take getting it out and running it hard to get it cleared out.

For me it started happening after adding the K&N filter to the stock air box. I did the stage one right after I got it new last year. Then I got rid of the AIS late last year. It does seem to happen within the first few miles for me, so maybe it just needs to warm up a little longer. I still get the popping on decel all the time so maybe an adjustment to the PMS is in order as well.

Boy, you guys are good!! I'll try to answer the questions first. The K&N is in the stock air box it did not start real soon after the K&N, stage two exhaust and removal of AIS. I didn't really pay attention to the mileage but would guess it ran fine for 5 or 6 thousand before this problem started. It sat quite a bit over the winter and this really got my attention this spring as I got back to more riding. Also, I have tried the seafoam thing and have always used a little MMO in about every third tank.
When I originally did the mods, I assumed a re-jet was in order, but it ran so well that even the members of this board said to leave it alone.
Two things you mentioned really got my attention. The PMS adjustment makes a little sense and that's something I haven't tried; also I have had the exhaust off before this happened so a good check for leaks would also make sense. Give me a couple of days and I'll let you know what I've found.
Now, anybody got a recipe for low calorie oatmeal cookies?

Did you use fuel stabilizer when you stored it for the winter? Did you turn off the gas and run it until it died?


OATMEAL COOKIES (LOW CALORIE)

1 1/2 c. quick cooking oatmeal
2/3 c. butter, melted
2 eggs, beaten
1 tbsp. liquid sweetener
1 1/2 c. flour
1/2 tsp. salt
2 tsp. baking powder
1/2 c. skim or lowfat milk
1 tsp. vanilla
1 tsp. cinnamon
1/4 c. raisins

Measure oatmeal into mixing bowl. Stir in melted shortening, mixing well. Blend in combined eggs and sweetener. Add sifted dry ingredients alternating with combined milk and vanilla. Mix in raisins. Drop by level teaspoon onto oiled baking sheet. Bake at 400 degrees for 10 to 15 minutes or until golden brown.

I just went through the same thing with mine, it turned out to be the vacuum cap on my manifold was trashed it was sucking all kinds of air and popping like crazy all the time except under throttle!

Musky wrote:
Did you use fuel stabilizer when you stored it for the winter? Did you turn off the gas and run it until it died?


OATMEAL COOKIES (LOW CALORIE)

1 1/2 c. quick cooking oatmeal
2/3 c. butter, melted
2 eggs, beaten
1 tbsp. liquid sweetener
1 1/2 c. flour
1/2 tsp. salt
2 tsp. baking powder
1/2 c. skim or lowfat milk
1 tsp. vanilla
1 tsp. cinnamon
1/4 c. raisins

Measure oatmeal into mixing bowl. Stir in melted shortening, mixing well. Blend in combined eggs and sweetener. Add sifted dry ingredients alternating with combined milk and vanilla. Mix in raisins. Drop by level teaspoon onto oiled baking sheet. Bake at 400 degrees for 10 to 15 minutes or until golden brown.

I would also check the vacuum plug that is installed under the tank when pulling the AIS - this will cause backfiring symptoms similar to SVS... - RK.

I think I figured this out on my bike. The fact that it only happened for a short period a few times after removing the AIS and changing the air filter would lead me to believe that I don't have any vacuum leaks.

What I found was that the choke was loose and had a mind of it's own. I tightened it up so that it wouldn't go in and out on its own anymore, and also I found that I need to warm the bike up according to Yamaha's proceedure of Full Choke to start, wait about 10 seconds and go to 1/2 choke, wait about a minute and go to no choke to finish the warm up. After a 2 or 3 minute warm up, she runs like a top.

Damn! That musky is good isn't he? I thought I might at least stump this forum asking for recipes.
Found an exhaust clamp that wasn't very tight, but haven't run it yet. I'm also planning on doing a little tweaking with the PMS.

Tealw1, I have improved my warmup procedure and am sure that helped some.

tapeit59, I'm not sure what you mean by the vacumn cap on the manifold? You are not dealing with a genius here.

musky, No stabilizer. I don't really park for the winter, but don't ride nearly as much. Probably ride
about 1/3 of the miles I run in the summer.

rkoch, If the vacuum plug you mention is the same as the vacuum cap mentioned by tapeit59 then I know
what we are talking about and will check it.

Like rayjay says: "the hotter she gets, the hotter she gets!" That may be a large part of this.

Thanks everyone and I'll let you know how the cookies turn out.

It's the one you put on when you remove the AIS!