Jetting issues/sizes

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tbracelin

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Location
Oklahoma City, Oklahoma
I recently installed an HMF slip on and changed the main jet to a 145. Everything is good except for it is now slower and cuts out aroung 46mph. Bone stock with a K&N filter I could hit 50mph. Anybody know if this is because the jet is too big or what?
 
I just did the same mods on mine a month ago but I still have the stock filter. I'll be changing that soon though. After the pipe I put the 140 jet in and it was a huge jump in power all the a way across. Then I put the 145 jet in and it had even more power, but cut out at the top. I took the air box lid off and got another boost in power and it's smooth all the way across. I'm not sure what the top end is but I'd guess around 50.

I hear a lot of different results from what seem to be the same mods. I wonder how much octane has to do with it though. I usually run mid grade.
 
I usually run 91 octane. I had the K&N filter before any other mods and was hitting 53mph. Now with the HMF pipe installed and the main jet changed to a 145 it is slower and cuts out. To be honest I can't tell much of a power change and I was running it with no lid on the air box too.
Mark said:
I just did the same mods on mine a month ago but I still have the stock filter. I'll be changing that soon though. After the pipe I put the 140 jet in and it was a huge jump in power all the a way across. Then I put the 145 jet in and it had even more power, but cut out at the top. I took the air box lid off and got another boost in power and it's smooth all the way across. I'm not sure what the top end is but I'd guess around 50.

I hear a lot of different results from what seem to be the same mods. I wonder how much octane has to do with it though. I usually run mid grade.
Click to expand...
 
tbracelin said:
I usually run 91 octane. I had the K&N filter before any other mods and was hitting 53mph. Now with the HMF pipe installed and the main jet changed to a 145 it is slower and cuts out. To be honest I can't tell much of a power change and I was running it with no lid on the air box too.
Click to expand...

Maybe I should have removed my air box cover and saved my money on the exhaust and jet. I hear others say they're running your set up with a 150 main and works great. It drives me nuts that so many people are having problems with the same mods others have success with. I'm not going back out for a few weeks but I'll drain my tank and run 91 octane next time and see what happens.
I'm sure you checked it, but is it possible that your filter is dirty an not allowing enough air in? Do you still have the stock air filter? Try it and see. Who knows.
 
you should get higher pilot jet and raise the needle. then try higher main jet. k&n filter is bitch to tune with a free flow filter.

lean jetting should produce backfire and pigning, very lean condition will shut the engine.
rich condition produce burpeling and wont rev up but will not shut the engine.

i have 98 wolverine 350 with aftermarket exhaust and uni air filter , i running 155 main jet and 55 pilot jet .

a well tuned engine should idle proprely without choke wien outdoor temperature is warm
 
I'm in Oklahoma City so the outside conditions are the same as you. I just cleaned my filter and run it with the outerwear. I love the sound of the HMF pipe but had much better top end with the stock pipe.
 
I was told that I only need the main jet. Does the whole kit make any difference? I'm going to put the airbox cover back on. Only took it off because of the way it was running at top end.
 
you must learn to jet a carburetor if you want to do mod on your bike . if you wont bring your bike to mechanic.
 
Nekrofilliak-I think that is why I put the jet in. They only call for the main jet to be replaced for what I've done which is an HMF pipe and a K&N filter. I put in a 145 main jet and wanted to know how other's responded to the same.
 
tbracelin said:
Nekrofilliak-I think that is why I put the jet in. They only call for the main jet to be replaced for what I've done which is an HMF pipe and a K&N filter. I put in a 145 main jet and wanted to know how other's responded to the same.
Click to expand...
Yeah Nekro if you click my name or read you will see:bird: I got on this forum to get ideas, network and keep up with other Wolfy riders. I spent too much time in Iraq to deal with an idiot like you but their is one everywhere and I can clearly see you're the one here.
 
i suggest you that you write a signature with your bike . like you can see there no many mechanic here lol. Every bike are different and like i said try to learn to jet the bike yourself , buy jet and try if the bike run better. Manufacturer like k&n say that there no need to rejet the bike, but is is false , k&n filter need to be rejet to work at it best. they says so because no one will buy them if they say that he need to rejet. pipe is the same it say only main jet should be change , trhat not true. a well tuned bike should idle well without choke and pull at every rpm without hesitation. Many rider dont really know their bike are out of tune ...
 
I agree it's best to know your machine, but common sense dictates that if someone else can give you the answer then take it. Surely someone out there can say they have the same bike and that they use X pilot and X main jets and have X results. I don't have the ability to ride daily or even every few weeks, so figuring problems out quickly is very important to me and I'm sure it is for others as well. If I have the time I'll gladly put it in to find the answers but I usually don't have that luxury.

Part of the reason I did the HMF pipe and main jet is because of what others said here. I'm happy with my results but don't understand why others have different results with the same mods.
 
Thanks Mark. Yeah it has pretty good result except with the top end like I said. It's bogs out at about 46mph. Also the idling is off. Wants to die at times unless you give it gas and other times it's fine.
 
Get higher pilote jet , and mainjet , and raise your needle ...
 
Anyone out there have an '06 or up 450 with an HMF pipe and jets??
What air filter?
What jets?
Any airbox mods?
I keep hearing so many good results and many poor ones. Are you happy with your mods? Do they perform well? Would you have spent your money on another mod??


I have an '08 with an HMF pipe and a 140 main jet, stock air filter. Huge upgrade. I have nothing negative to say about it. When I put a 145 main jet in I die at hhe top end and have to remove the airbox lid. It still runs rich there too so I'm putting the 140 back in.

Who out there is running the 150 main?? I know some of you are. How are you set up??
 
Mark seems like we have the same problem. What made you switch from the 140 main jet to 145 anyway? I started with the 145 and have problems with idle and top end cutting out around 46mph. I was running it with out the air box lid to try to compensate. I am taking it to the shop today to have a jet kit installed and have them get it set right hopefully. I'll let you know results this weekend.
 
I just put the 145 in to see how it'd work. I don't want to leave any power on the table especially when I already have the jet. I can't get enough air through the intake to make the 145 run right. I'm going back to the 140 for now.
I have thought about moving the battery to the storage tray and adding a boot from the intake to the battery box and adding a lid.
 
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