HELP jetting prob with my 06

[predatorgh7]

I need some help with jetting on my 06 450r. I got a full HMF sport pipe, and a 13.5 to 1 piston. I finally got a new plug last week and put in thurs before I went South Carolina for the GNCC. On wed I thought I would take it out to check it and the porcelain was still white so its beyond lean atleast that wat i think. I originally had a 165 main, 48 piolt, HRC needle 3rd clip from top, stock leak, air screw 2.5(from all the way turned in) and a boyseen quickshot. So yesterday I played with jetting all day. First I changed the pilot to a 50 it didn’t really change the color but the throttle response seemed better. Next I kept the 50 in and went to a 170 on the main and the porcelain got a tiny bit darker. So then I try turning the air screw out to 3 turns and it seemed that the starting got worse and the plug didnt change. So last I put a 55 leak jet in and put the clip down one on the needle(4th clip) and put the air screw back at 2.5 and again it helped very little and the porcelain got a little more darker but very little and it started first kick after I got it back together but after that it wasn’t that great but it seemed a little better but not much starting wise. Im lost on wat else to try can anyone help me out!!!!!!!! I would really appreciate it!!!

To read a plug u look at the porcelain right? my dad has only known to look at that and same with my neighbor. And I found a website that says to check jetting by looking at the base ring(right above the threads) I also found a forum on hmf and they gave the same website. So I’m not sure wat to go by?

http://www.dragstuff.com/techarticle...ead-plugs.html

[the Z Man]

For starting issues check your valve lash, could be out a little, get er spot on and she starts alot easier..

[predatorgh7]

I just got a head service done by GT thunder about a month a ago and ive only raced twice since that and ive checked my valves every week and there right where they should be. My main concern is the jetting not being right i dont want my quad to get messed up if its to lean..

[400exrapes]

I would say go up a size or two on the main jet, keep your 50 pilot in there or go up to a 52 pilot and then test it out.

[predatorgh7]

will i went out and check the plug again and it was coal black. I putted around my house last night and just did a couple wheelies and try to practice starting and I didnt really get on it. and then just now I rode had for about 10-15 min and pinned it 3rd or 4th gear and shut it off and the porcelain went back to basically white its darker then before though. so that would mean my low end is to rich then right and that my main is wat needs fixed like 400exrapes says.

[04'400ex'er]

You should have the clip on your needle set on the 4th notch, I believe. This may be whats throwing you off.

When was your bike last jetted correctly, that you know for sure? What mods have you done since then, or did you do all your modifications at once? Give more specific details about how your bike is acting and what makes you think you need to rejet.

First off, you need to work on one thing at a time. Don't get mixed up with trying to tune several portions of the carb at the same time.

If I were you, I would put the jetting back the way it was, with the needle on the 4th clip. Begin with the main jet, richening it one size at a time until your bike quits revving out and begins to bog. You will know immediately once you start it and try to rev when you are at this point. Back it off one size and your engine will be plenty rich enough on the main.

This could be all you need, or you may need to play with the pilot some next. That will be your call at this point as far as how your bike starts and idles, or if you want to do a plug check. Repeat this step if you think you need to richen the pilot, using the fuel screw to fine tune it. Nothing may be necessary at all however.

I believe you must ride in like 3rd gear at near WOT for around 10 seconds, then shut your bike off with the kill switch to do a MJ plug check.

For the pilot, I think you can simply let the bike idle to do a plug check.

Try this and then report back for info on the pilot.

[400exrapes]

well this is what helped me for jetting
Pilot Jet:0-1/4 throttle(and nuetral/clutch)
Needle Clip: 3/8-1/2 throttle
Main Jet:1/2 - Wide Open Throttle

So tell me where the problem is occuring during what part of the gear your in.

[04'400ex'er]

Originally posted by 400exrapes
well this is what helped me for jetting
Pilot Jet:0-1/4 throttle(and nuetral/clutch)
Needle Clip: 3/8-1/2 throttle
Main Jet:1/2 - Wide Open Throttle

So tell me where the problem is occuring during what part of the gear your in. Correct, we need to know what your bike is doing to help you further with your jetting. But like I said, I would start with your main simply because you can do it with the carb still on the bike. Once you get that done then cmb.;)

[400exrapes]

yeah a 50 pilot is fine, and actually you might not ever have to touch that needle clip, i never have, and i probably never will. so let us know where your having the problem.

1.Is it in neutral/clutch?
2.Is it between no throttle and 1/4 throttle?
3.Is it between 1/4 throttle and 3/8 throttle?
4.Is it after half throttle?
5.Is it hard to start?
6.Do you have a picture of your spark plug?


If you can answer all those questions im sure we can help you, and tell us what your current jetting is too.

[04'400ex'er]

He has the HRC needle which I believe is the CRF needle, it needs to be on the 4th clip. Thats where mine is and all I have is an exhaust, filter and no lid.

[400exrapes]

okay so now i need all those other questions answered too so we can figure out his problem.

[predatorgh7]

im going to work on the main jet first like u said instead changing stuff like i was but the highest jet i got yeasterday was a 175 and172 so i might have to get more tom but ill check the the plug at each part of the throttle like u said and c wat the plug looks like. it seems fine when im riding it in every gear it dont back fire or pop or anything like that. it just that the porcelain is basically white and i checked the plug like i said before in 3 or 4 gear pinned and pulled in the clutch and shut it off. After i put the 50 in when it just sitting there and u hammer the gas it revs right up it dont want to die or cut out like it did more with the 48 and ridin really low in first gear where it about to die and u hammer the gas it will take off no prob with the 50. Starting is prob my biggest prob i just got a new timing chain so it alot better now but when it gets really hot or just riding for a few min it doesnt always want to start back up when i stall it. It takes a few kicks for it to start back up and when it does start back up its like it dont want to like it doesnt have any gas or the idle is way to low it slowly starts back up and giving it gas help alittle (if this make since at all im not sure how to explain it) or when i get it warmed up a little to practice my start it dont want to always start first kick. down at SC for the gncc it started right up off the line first kick. It will also back kick ALOT.. also sometimes when i go to start it it will pop when i kick it. I also dont per load it either i have no idea how to do that im sure that would help i need to learn how to do that I think my dad knows how to but iv always just kicked it.

If i can get a decent enough pic of the plug ill put it on here.

I also got the 13.5to1 piston and new cylinder and hmf full pipe back in about jan-feb. last year i had a slip on hmf and i got it converted to a full pipe for this year

ive never had anyone jet it before it seemed good last year we had it at wat hmf recomended. now i had wat they recomended for the full system and the plug looked way to lean. my dad and i are still learning about this 450 stuff it alot diff from a 300.

I think it needs rejeted cuz the porcelain was still white when i took it out of my quad on like wed.

Ill leave the clip at the 4th from the top. i did have it at the 3rd cuz that where hmf said to have. Also when i took the needle out to change the clip i noticed that right in the middle of the needle it black all the way around it was about a finger nail long give or take alittle is that normal

[400exrapes]

Alright well, the backicking is okay, that means you have alot of compression. Start the quad with choke on and then right away take the choke off, and if it dies start it again with the choke on because if you try starting it when its cold without choke, then it will back kick on you. Your pilot seems fine, take a picture of the spark plug and then we'll go from there.

[400exrapes]

And, dont twist the pilot jet out anymore than 2 1/2 turns, because then if you do that means you need to go one more size up. I would reccomend leaving it at 2 1/2 turns.

[predatorgh7]

when i first start it it dont back kick but when it gets warm or hot is when it does it the most and the wierd thing about it is last year (i got it new around xmas of 06) i put the kicker in about this time it never backed kicked on me till the fall and that when all the starting prob started to happen but i got the head cleaned up and a new timing chain for this year and it still does it but i guess that prob cuz of the higher compression piston. i know back kicking is common though.

[predatorgh7]

u mean the air screw right i just want to double check

[predatorgh7]

im also running cam2(114 octane) mix 3 to 2 with 93 octane(3gal of cam2 and 2gal of 93). if that helps at all.

[predatorgh7]

it wont let me put them on it says the pic is to big

[400exrapes]

send it to my email djo_baseball_player@yahoo.com

And did you notice any problems in certain parts of the throttle you were giving? Put that HRC needle on the 4th clip, and then let me take a look at the plug. Whats the stock jetting on the 06 fcr carb?

[04'400ex'er]

You need to put your jetting back the way it was like I said at the beginning of this thread when you move the clip to the fourth position.

Then focus on your main first, don't even worry about your starting problems yet. Besides, the needle could take care of that.

Have you ever thought about putting your bike on the dyno? You can get it jetted spot on for usually around 50-60 bucks.

[predatorgh7]

Ill sent it right now. I had the needle at the 4th clip and put the 48 back in it. and no it seems to run great through the entire throttle it didnt break up or any thing i didnt really ride it cuz it was rainning and muddy out. and i could hammer the throttle and it would rev right up. im not sure wat the stock jetting is i know it a 70 leak and about a 42 piolt maybe and im not sure on the main.

The pics of the plug is with a 175 main, 48 piolt, 70 leak, air screw 2.5 (in from all the way) and a boyssen quickshot.

[predatorgh7]

I put it back the way it was like u said 175 main, 48 piolt, 70 leak, air screw 2.5 (in from all the way) and a boyssen quickshot. i put the main to a 175 that the highest one i had and it at the 4th clip.

I first tryed it at 1/4 to 1/2 throttle sitting in neutral. I reved it and held it for about 10 sec and hit the kill switch while it was reved the plug was a tan/ light brown with some black at the top. The 2nd time was in 4th gear pinned and I pulled the clutch and hit the kill switch it turned back to prue white. I also just got the plug today

thats my plan now to foucs on the main first I want to get jetting right then worry about starting im sure that why it not starting in the first place atleast i hope.

I would take it to hmf or gt thunder and have them jet it but Im past tight with money right now I cant afford it. im lucky to make it to just gncc's and keeping my quad running. I hate bills :grr:

[400exrapes]

good news, plugs are good. Youve been reading the wrong part of the plug and they were brown. Your main jet is possibly too rich BUT its a darkish brown and fades to black at thetop so try going down 1 size main jet. But your pilot jet is perfect so dont touch that. I actually think your fine i think its jetted fine. but if you want go down 1 size on the main jet and take a picture of the plug and send it to me again.

[predatorgh7]

so the porcelain being white is ok? wat part of the plug do u look at?

and thank u guys for the help i really appreciate it

[400exrapes]

http://www.aa1car.com/library/reading_spark_plugs.jpg

[400exrapes]

Look at my plug, the stock jetting in mine from the guy before my was a 148 main and a 48 pilot. I put in a 150 main and a 50 pilot. Ignore the burger king cup in the backround, heres the blurry but colorful picture of my plug that i went and took out for you!

[predatorgh7]

thanks for doing that.. ur plug looks great. but my porcelain dont look like atleast when i had it in 4th gear and hit the kill switch it was white and it was the brown color at 1/4-1/2 throttle unless thats normal for it to go white it should be brown instead of white shouldnt it? the 1/4-1/2 throttle is for the piolt and needle and the other way is for the main isnt it??? iv looked at three diff website now one says to look at the porcelain another says look at the base ring and the one u gave to looks like u look at the porceain also.


Thank u for taking the time to help me out!!!!!!!!!!!!!

http://www.dragstuff.com/techarticles/how-to-read-plugs.html
http://www.jetsrus.com/main_page.htm

[predatorgh7]

Originally posted by 400exrapes
Haha i've got good news for you, your plug looks fine and you've been looking at the wrong part. In both of those pics the plug is a darkish brown, if anything go down 1 size on the main jet, but your plug looks fine its a brown color which is what you want. The white part you've been looking at is the wrong one to look at.

I know the plug in the first pics that are tan/brown is good and right where it should be but why did it turn back to white when i had it pinned in 4th is wat im trying to understand now i guess. It shouldnt do that should it? it should stay brown right?

[400exrapes]

those are different types of spark plugs, the one for the quads are flat at the top, and those ones have like the porcelin sticks out. i'm confused what you mean by it went to white, if its brown at thetop and like blends into white down below then your fine.

[predatorgh7]

wat im talking about is wat the plug looks like in that last pic (it should be the last pic). the porcelain is all white that happened when i was in 4th pinned and then killed it. It went from the brown in those first pics to white in the last pic. so i guess im trying to figure out if thats normal or not, or if it suppose to do that, or does it mean that the jetting is still off. I tought the porcelain was supose to stay a tan brown and not go back to white.

ill send u a pic of it so u c wat i mean

[400exrapes]

I sent you an email, can you tell me what your current main jet is?

[predatorgh7]

I got a 175 in it

[400exrapes]

buy the next three sizes up from there, i'm going to say like a 178 or a 180 is what you'll need.

[predatorgh7]

ok thank u ill get some jet and let u know wat happens

[predatorgh7]

i tryed a 190 and 185 and the porcelain was still white. i couldnt get a new pic of it the camera is dead. but the pic in the last eamail i sent u it looks the same but the base rings right above the threads and the first couple threads turned more of a coal black now but the porcelain was still white.

[400exrapes]

Okay, I guess you need to keep going higher, AND check everywhere for leaks in those seals and airbox, and tubes leading from the airbox to carburetor, and carburetor to cylinder. otherwise keep going higher because its too lean.

[400exrapes]

try 195-200 if those are the next sizes, is your lid off? are there any other mods like porting or something that we should know about?

[TRX450RACER174]

Put it back to the 168 or 165 mj you guys are steering him in the wrong direction this is a 06 not a 04/05 and that jetting is way to much for even the mods listed on a 06.

[400exrapes]

Originally posted by TRX450RACER174
Put it back to the 168 or 165 mj you guys are steering him in the wrong direction this is a 06 not a 04/05 and that jetting is way to much for even the mods listed on a 06.

I've seen his plug, and you havent. That plug is pure white and as far as i know of that means lean. AND if its lean than he needs to keep going higher, if you want to explain how thats wrong than please do... and take no offense I'm not mad.

[400exrapes]

I took a picture of his plug so everyone else can see.

[TRX450RACER174]

First of all i read your mods and correct me if im wrong you have a HMF exhaust and a 13.5 to 1 piston with no other mods? I did not see you mention a cam or a/f but even if the box lid is gone it wont make much of a difference.
So now you are mixxing 114 oct race gas with 93 octane right this alone burns different that just regular 93octane, so if you look at my mods on my bike and granted i live in Cali i am running a 168 main jet with the HRC carb mods and a HRC cam with a BIG GUN race exhaust K&N filters and a stock 12.5 to 1 piston and that bike was tuned on the dyno at K&N.
So you guys are telling him to go to a high 180 to low 190 main jet on a 06 motor thats just over kill imo this bike and carb do not need that high of a main jet, i have tuned many FCR carbs on Honda's and Yamaha's and never been over a 170 in any of those machines, all i can tell you go back where you started put a 160 main in it go back to a 42 to 48 pilot and a 55 leak jet and start from there. In case you didnt know the leak jet is for off idle bog i see you changed your leak and have a boyseen quik shot get ride of one or the other, I dont tune to plug color so i think you are worrying a little to much about do a search and see everones tune on a 06 up bike i don't think anyone is running some extreme jetting unless they have major port work,carb work and a high comp piston.

[400exrapes]

You can go ahead and try the 165 or whatever main jet, but that white plug is a lean condition so going down to a smaller main jet makes no sense to me but its not my quad so go ahead and try something new I guess.

[predatorgh7]

yea thats all i have done is the full hmf and the 13.5 to 1 piston lid off and i got the stock cam but im getting the hrc or crf or some kind prob next month with that $600 we get back. I only tryed to change the leak to a 55 with the quickshot but i put the stock one back in

i called laz at gt thunder this morning and talked to him about it. he told me between a 170-175, and a 50 piolt so i just put the 50 and 170 in it for now atleast. and he said that the plug color isnt that big of deal it more how it runs and just cuz its white on the end doesnt mean that its not jetted right u got to cut the plug to truly know the main he also said he could take brandons plug out after a race and it be like brand new also(and dont quote me word for word though this is basically wat he said except wat to jet it at i know thats wat he said)


THANKS FOR THE HELP

[TRX450RACER174]

Cool glad you got it figured out as long as it runs good you are on the right path.

[400exrapes]

yeah, agreed.