450r carb running lean......

[timp224]

I have a 07 400ex stage 2 hotcam, full exhaust, open air box k&n, just picked up a 04 450r carb. I put the needle clip in the middle, and im running a dyno jet 180 main, and a 50 pilot and fuel air mixture out three turns. When i start the quad and let it iddle, my header will start to glow red. This is a sign that im running lean from what i understand. Can anyone help?

[trailrider894]

Well if you are just letting it sit there and you are hitting the throttle pretty hard it will glow. Is it heating up quickly while just idling?

[honda400ex2003]

do you have the hot start plugged with a plunger correctly?

i dont have my exact stuff here now but i believe i am running a 52 pilot in mine with the needle on the 3rd clip and a 168 in my 416 with a slip on open box and filter. It has a stage 2 in it also with a light p&p. to show you what you are up against. you are most likely way too big on your main and too lean on your pilot as a reference point to go from. if it is colder outside i would go with a 54 pilot. Im talking something like 20-30 degrees or less. check out rons dyno thread, he is running pretty much the same with a stock cam i think. i think he is around a 162 or 160 from what i seem to remember. it has been quite a while since i have checked my specs and rons specs. lol i have been so busy lately i forgot my specs... sad :( steve

[timp224]

I had a keihn 180 (that is the same as a dyno 168) in at first and it was glowing red, so i put the 180 dyno jet in it today. I noticed that it only glowed red at an idle, when i gave it gas the redness went away....maybe i need a bigger pilot.......it runs like a raped ape with a load on it!

[honda400ex2003]

you will need a bigger pilot or at least tune what you have correctly. probably a 52 would be my guess. steve

[timp224]

i ordered a 54 pilot, i figured that if it is too big, i would bring in the fuel air mixture screw. Before i put the 450r carb in i was running a 170 main in my stock carb, it ran perfect. I read on these forums that you would need a bigger main in the 450 carb, so i put the 180 in. One thing i noticed is that at an idle, if i slam the throttle it will bog out, it does that now and it did that with the smaller main jet. When i am riding it, or when i slightly rev it up, it has no bog at all, it screams through the power band. Is it normal to have a slight bog from an idle when i slam the gas?

[trailrider894]

Originally posted by timp224
i ordered a 54 pilot, i figured that if it is too big, i would bring in the fuel air mixture screw. Before i put the 450r carb in i was running a 170 main in my stock carb, it ran perfect. I read on these forums that you would need a bigger main in the 450 carb, so i put the 180 in. One thing i noticed is that at an idle, if i slam the throttle it will bog out, it does that now and it did that with the smaller main jet. When i am riding it, or when i slightly rev it up, it has no bog at all, it screams through the power band. Is it normal to have a slight bog from an idle when i slam the gas?

No it is definetly not normal. When the engine is cold? maybe. But after its warm it should rev to kingdom come without bogging.

[honda400ex2003]

i run 2 jets lower with my 450 carb than with the stocker. it all depends on setup. if you were at a 170 main you wont be more than a 172. a 170 with your setup is still pretty big already imo. steve

[timp224]

the quad runs great when it is moving, has way better low and mid range power, top end feels about the same as the stock carb. The only time it bogs is when it is idleing in neutral and i hammer the gas. I was really just concerned with the head pipe glowing red at idle. I hope its just the pilot.... what is a AP pump?
I have read on other forums that people had the same problem with a bog if they slam the gas from idle.....

[honda400ex2003]

it is the accelerator pump. that wont cause the issue unless it was messed with. your jetting is too rich on the main thus causing the bog and too lean on the pilot causing the glowing pipe as i have said before. steve

[honda400ex2003]

examine this closely...

http://www.exriders.com/vbb/showthread.php?s=&threadid=445695&highlight=jetting+placement

do some plug chops, read the plug. tune accordingly for each. you should just about be able to tune the pilot perfect even with the 50 in it now. just listen to the idle of the machine and tune according to the directions. do some chops on the main with a new plug to see how rich you are. unless you have a leak somewhere on your carb you will be too rich running a full exhaust and a filter w/ lid off. steve