If you are rich in your main jets, can this cause you to loose top end speed?

I am running 134 frnt and 138 rear with the mods listed below, it does not seem to hesitate and wheelies easily, the dyno jet kit states to run 132 frnt 136 rear with after market exhaust, but then the diamond g racing snorkel adds to the air flow and recommends stepping up your mains, this is the reason i moved to 134 138, do you think this is on or too rich, i still have to do a plug check, under 1000ft sea level

 

It can cause a top speed loss; have you lost top speed? Heavy tires and clutch spring changes can cause top speed loss also.

 

Ginchy,

I'm running a T4, K&N, Diamondg snorkle & 3-1" holes in airbox lid. I'm also below 1000' elevation. I run the dynojet kit at 132f/136r, 5th notch on the needle and 2.50f/2.75r on the air screws. The bike runs strong and the last plug check was a little on the rich side. Every bike is a little different but just thought you might want to compare.

 

Scotia,

I agree that everybike is different but it is a mass produced engine, could i actually be that much different than you, we both have aftermarket exhaust, k&n, and snorkel, i dont have any holes in airbox, i am not fouling plugs and im not getting any hesitation, but it could be rich, it seems rich because it will smoke a tiny bit after it is warmed up and you give full throttle then let off, it will not miss, and the smoke is not bad, but it gives a little huff,

I will once again delve into the carbs and swap the jets, Ill tell you one thing, before I jetted the 650, i did not have the first clue about a carb, but since then, i could probably build one, i dream about carbs in my sleep, hehe, got to love it

Also, did your top end improve with the mods, i do believe that my 25 inch dirt devils can be tricking me because they are really only 23, what a bunch of bs, but ive also read about how other people on the forum fell into this trickery.

Anyway, I appreciate the responses, Thanks

 

Ginchy,

I think you would be ok to jet down to the 132f/136r. I really don't see any problems.

I've got a set of 28" 589's installed so my top speed is out of wack. I get in the low 90's (kph not mph).
I've ordered a set of ATR's which should get me back close to stock size and weight. I'll let you know how I make out (they're backordered until May though). Play with the airscrews, I know a 1/4 turn makes a hugh difference in response. Let me know how you make out.