I am having some issues jetting my wife's Wolverine 450 after installing a GYTR exhaust and K&N filter. We are at about 900 feet and was around 50 degrees when testing. I am starting to wonder if the stock jetting on this machine is a little rich? I have been trying to avoid spending the cash on a full dynojet kit being that I have quite a range of Mikuni jets lying around. The stock Mikuni jet is a 131.5, HMF recommends a 140 main and I have read that its a little too rich for some. So....I started with a 137.5, ran good until top end. Top speed stock was about 53mph, with the 140 it dropped to 48mph. I removed the airbox lid and gained 1mph. So, I put the lid back on and dropped one jet size to a 135 and got it to 50mph. Reluctantly I dropped down to a 132.5, one size larger than stock and it tops out at 51mph, pretty close. Just for giggles, I removed the lid again and it jumped to 52mph on several runs. So it seems that with the lid on, I should drop it back to stock...........but its really confusing as to why this would be the case. I have jetted at least six other quads over the years and always jumped at least one main jet size after a slip-on exhaust.

To add fuel to the confusion fire, according to the instructions online of the dynojet kit, below 3000 feet with a high flow exhaust, they recommend a dj132............which a conversion chart says is equivalent to a Mikuni 124..........5 sizes smaller than stock!!!

Sorry for the long post, I am just really perplexed about this situation and wondered if anyone could give me some insight or at least what jetting you are running at your elevation?

Thanks

 

i kinda have the same problem with my kodiak. i have the HMF slip-on and no lid and im on the stock jet, although it has a a hanging idle it runs good.

 

Interesting, so did you attempt to re-jet and just come back down to stock?

 

yes i first bought a 135 and 140(stock is a 132.5) and the 135 was kinda rich and the 140 was blowing black smoke! im thinking i need a bigger pilot though, i can get rid of the hanging idle by having the choke out 1/4, and the idle adjustment all the way in. The topend is perfect, no spitting or sputtering. and low end is great, a little tug on the bars and the wheels come right up! i just dont like the fact it like the stock jet! i will hopefully get it tuned perfect sometime.

 

Interesting, I plan to put the main jet back to stock this weekend. I know the stock main is a 131.5 for us, I currently have a 132.5 in there and it seems too rich.

 

If you really want some jetting fun about 5 hours worth, snorkel the wolverine then jetting becomes fun. I ended up with stock jet 131.5 and stock pilot jet I have the needle clip from the FMF jet kit at the second slot from the bottom then 2 full turns on the fuel mixture screw and finally got it right I had a real aggravating lag between idle and mid range. i tried every combination before I finally got it right. The tech at FMF said after snorling it always runs lean and that is not right in my case.