I thought I had my jetting right...

[danniheyj82888]

1st and 2nd gear seem to be fine but 3rd and 4th gear seem to bog in the low to mid rpms, if I get on the gas hard from the beginning. If i roll on the throttle slowly it seems to be better and pull a lot harder. Then 5th gear is a little better and screams. I have a 165 main jet and a 48 pilot. I havent adjusted the fuel screw. Could that be why? Or am I too rich? I have the HMF Sport Series Slip-On. Everything else is stock w/ airbox lid on. Any help would be nice from anyone else that has a setup like this or knows something about the jetting.

[GPracer2500]

Focus on throttle positions, not what gear you're in or what rpm your at. Each carb circuit is responsible for metering fuel within a certain throttle opening range (0-1/4, 1/4-3/4, 3/4-WOT). The carb doesn't really care what gear you're in or what rpm you're at.

Sometimes it's helpful to choose specific gears for testing certain throttle ranges. For example, you wouldn't want to test WOT in 1st because you'd just bang of the rev limit. Taller gears are generally more useful for testing because in a low gear an engine can somtimes rev right through a misfire, somewhat masking it's presence. But the bottom line is to focus on where the throttle is positioned when a misfire occurs--that's what indicates which circuit is miss jetted.

My guess is your main is way too big for running with the airbox lid on. I bet if you take it off it will run better. If you must run the lid try jetting it way down.

[ryann mx68]

what he said^^^^

a 48 pilot is really fat for a o6r. most are running with a 42 [stock] pilot, some may be at a 45.

a 165 main is to big for a 06 with the lid on.

also get a adjustable fuel screw, it makes life much easier

[danniheyj82888]

Thats what I thought but I called HMF and checked their website and that is what it said. When I get on the gas hard like WOT it bogs... I thought that was because it was way too big of a main. so I tried taking my lid off and it ran worse.. Im so confuesed on what to do.

[hemp450r]

try jetting with a 145 main, 42 pilot, needle third clip from top, and leave your lid on, take the snorkel out, if not CHECK YOUR PLUG after running in top gear wot, cut the engine with your thumb into the throttle, check the colour, wet and black main too rich, or needle too high, if its white too lean,or needle may be too low, what altitude are you at? just my thoughts????

[ryann mx68]

06 450r / exhaust / no lid

these are ballpark, each bike is diff. but this will get you very close

main jet: 165 -170
pilot jet:42
needle: 4th position [crf 450 needle]
a/f screw: 2-1/2 turns out

try these without your lid and see how it runs. i cant help with main jet #'s with the lid on. at least drill some holes and put those UNI vents in it. you need to let it breathe!!!

note: taking the lid off will make you do this :D :D :D :D

[Architects]

Originally posted by danniheyj82888
Thats what I thought but I called HMF and checked their website and that is what it said. When I get on the gas hard like WOT it bogs... I thought that was because it was way too big of a main. so I tried taking my lid off and it ran worse.. Im so confuesed on what to do.

You sure that wasnt for a full pipe. Your only running a slip on and a 165 seems huge to me.

[400exrider707]

Originally posted by Architects
You sure that wasnt for a full pipe. Your only running a slip on and a 165 seems huge to me.

HMF is notoriously horrible for suggesting a waaaaay too rich jet. I think for a 400ex with just their full system they recommend a 200 main. I've never seen any 400ex run a main that big.

[ghott]

HMF Recommends a 180 main jet for the 450R Full sport series. It is really frickin close...and dyno proven...on my bike :).

[tooanxiousii]

First of all your running to big of a jet for having the air box lid on ... Take the lid off or go to a smaller jet and second you NEED to change your leak jet that is the mean cause for the low and mid end bog on the new 450r's because they went to the 40mm FRC carb.. This carb flows alot of air more than the old 04-05 carb did.. The leak jet you want is #55 that should do you good!!
You do need to Chance your pilot back to stock 42 that is way to much fuel ... One more thing that will help is a HRC neddle with the clip on the middle notch.. (The stock neddle is not adjustable)
I hope this helps you!!!

[tooanxiousii]

What all do you have done to you 450r "Ghott"???

[ghott]

Just little stuff...nothing too dramatic.

13.1:1 Wiseco
Ferrea Super Flow Intake Valves
Sparks Filter
Airbox Lid off
My own little Valve Cover/Crankcase breather mod
HCS2
DASA pipe

I have a link in my signature to a page that I made for my 450R also...you can check it out if you like.

BTW, good advice on the jetting. The 180 main I mentioned is for the 04/05 carb, NOT the 06/07.

[400exrider0004]

Im running 175 main, 55 slow jet(pilot), NCVQ needle and 4th position. Im still lean with the slow jet but I can get much richer because it wont start. I can only tell that i am lean because my header glows. I would try 55 pilot. Like tooanxiousii said.

[tooanxiousii]

Not a 55 Pilot!!! A 55 Leak jet that will help you get more fuel in your motor for pump in your carb.. The Leak jet is located in your float bowl It's very small.. Your carb isn't spraying enough fuel from the pump stock thats why when you roll on the gas it's fine because your carb can keep up ... But when you hammer the gas your carb ( your flat slide) opens so fast you don't have the fuel it needs...(to much O2 and not enough Fuel) The different leak jet will let your carb spray more fuel from the pump and give you a better mix (O2&fuel)..

[Shaftner87]

I see that most of the people on here are giving you different info. I have a '04 450R with the HRC kit, rev box, FMF Titanium pipe and I had to jet mine all the way up to a 193 main jet for it to run right. It runs great but a little hard starting in the winter. I think your just gonna have to try different sizes but make sure you use Honda jets or the original carb manufacturer jets

[ghott]

Originally posted by Shaftner87
I see that most of the people on here are giving you different info. I have a '04 450R with the HRC kit, rev box, FMF Titanium pipe and I had to jet mine all the way up to a 193 main jet for it to run right. It runs great but a little hard starting in the winter. I think your just gonna have to try different sizes but make sure you use Honda jets or the original carb manufacturer jets

04/05 carbs are completely different from the 06/07 carbs.

The user who posted this topic is asking the question regarding a 2006 450R.

[danniheyj82888]

Yea I do have an 06er but I am so confuesed right now, I dont even know where to start making changes lol.. I havent adjusted the fuel screw yet.. if i do will it make a big difference or is my jetting too far off?

[tooanxiousii]

Originally posted by tooanxiousii
First of all your running to big of a jet for having the air box lid on ... Take the lid off or go to a smaller jet and second you NEED to change your leak jet that is the mean cause for the low and mid end bog on the new 450r's because they went to the 40mm FRC carb.. This carb flows alot of air more than the old 04-05 carb did.. The leak jet you want is #55 that should do you good!!
You do need to Chance your pilot back to stock 42 that is way to much fuel ... One more thing that will help is a HRC neddle with the clip on the middle notch.. (The stock neddle is not adjustable)
I hope this helps you!!!

Just try what I told you here and you will be happy!!!
The air fuel screw should be about a half of turn out from stock thats it...

You have alot of people telling the wrong thing because they are talking about jetting a 04-05 and they are Different..
Almost forgot you want to use Keihin hex jets NOT DYNO JETS

[danniheyj82888]

Yea I am using the Keihin Hex Jets.. Ill try what you suggested within the next few days and ill let you know how she runs! If anyone else has any suggestions let me know!

[tooanxiousii]

Let me know please!!!!

[hemp450r]

whats differant between dynojets and keihin jets? oh the adapter i think?

[danniheyj82888]

Well I havent had any time to mess with the jetting but today i rode a bit in my backyard and i took my lid off to see how it ran. It is terrible with it off, so I put it back on. IF you hit the gas hard from low rpms, it would bog so badly it would almost die... is this because my pilot is too big? If i take my lid off and go back to the stock 42 pilot and leave the 165 main in, will it run better? Or will I have to go to the 55 leak jet?

[450ERRRRRR!]

I'm running about the same set up as yours. I've tried a 48 and 45 pilot, both way to rich. Go back to the stock 42. Leave the airbox lid off. I'm running a170 main with a slip on exhaust with no bog or hesitation problems. You give it gas and it takes off!!
I think it's your pilot jet. Start there, but leave the lid off for good.
Are you running high octane gas like 91-93? This could be your problem too!

Try one thing at a time, start with the pilot and let us know what happened. Make sure to tighten the clamps around the carb so no leaks.

[GPracer2500]

You might want to get the HRC jetting from Honda. It comes with a main jet, a needle, and a leak jet. It's meant for running with no airbox lid.

The off idle stumble you're experiencing when you stab the throttle is because of the accelerator pump circuit. You need a smaller leak jet.

[tooanxiousii]

Originally posted by GPracer2500
You might want to get the HRC jetting from Honda. It comes with a main jet, a needle, and a leak jet. It's meant for running with no airbox lid.

The off idle stumble you're experiencing when you stab the throttle is because of the accelerator pump circuit. You need a smaller leak jet.

This is what I have been trying to tell you!!!