Jetting for uk

[Adam James]

Hi all I've done the free mods on my wr450 2006 ais removal, fmf powercore 4 can throttle stop screw, grey wire and air box mod what would be the best jetting for the bike now all mods are done I take it stock jetting will not be sufficient 

Many thanks 

Adam 

[Adam James]

From what I can see I should do 

48 pilot 

170 main 

I've took the jets out and I have an adjustable needle and it's on the 3 clip I think I need 4 clip with the other jets added I'm unsure about starter and leak jets if I have to change I read #40 leak jet and 70 starter to go with above jets but I'm unsure the info taken was at sea level witch I am but higher degrees its like 4 degrees here atm any help appreciated

 

[Adam James]

The need says gddus is that the stock needle? 

[Adam James]

Can anyone give any info?? 

[Jens Eskildsen]

Theres a jetting guide in one of the few first threads in this subforum ?

[jakob0045]

The stock needle for your bike is called #NFNT.

[Adam James]

Yeah mine says gddus so I don't no what needle that is then or from

[GuyGraham]

Do you have the workshop manual..if not get one from the yamaha austrailia site

It tells you in there what the stock needle code is

Usa and uk bikes are different...usa bikes used to have non adjustable needles as stock. Even uk bikes came with the 'correct' needle in a bag as the fitted needle was for emission purposes

[Adam James]

Apparently the gddus neddle comes in the de restriction kit when the bike was purchased along with a #48pilot#48pilot I'm changing the main to a 170 and fitted an adjustable fuel screw also done the ap timing will it be OK to use the gddus needle with the other jets

[Adam James]

My reason for rejecting is my bike was running in a lean condition and popping ect 

Any help appreciated as I'm new to this and trying to work it out

[GuyGraham]

Plug chopping is useless with modern fuel

They run shit with off jetting so you will know anyway

170 main and 48 pilot will be fine starting points

Use the needle from the 'bag'

PoppIng could be frOm airleak or blocked ACV but a properly tuned pilot circuit will pop on the overrun

[GuyGraham]

On 1/21/2019 at 1:59 PM, jakob0045 said:

The stock needle for your bike is called #NFNT.

That's the 'emission compliant' needle I think

Ignore the GD at the beginning of the code - the attached file will allow you to decode it

I had a DUQ in my 08, with a 168 main and 50 pilot

[GuyGraham]

Link to the 2006 WSM manual https://ownersmanuals2.com/yamaha/wr450f-2006-owners-manual-68547

You have the correct needle DUS

Extract

[Adam James]

Thanks a lot guy appreciate it, I'm going to go with the 170 main 48 pilot dus needle that I have on 4th clip position the leak jet I have in there is stock #50 I found another jet on the carb I'm guessing it's the pilot air jet it's #80 I'll take a picture of where it is also I'm going to check my float height. The bike was running OK it was a bit poppy on decal with stock exhaust but I managed to take off ais then I fitted a fmf powercore 4 end can and it sort of bog out at top end when u wot to quick my starter motor broke so I took it all out to fit new one and thought I may as well do the carb at the same time

[GuyGraham]

5 hours ago, Adam James said:

Thanks a lot guy appreciate it, I'm going to go with the 170 main 48 pilot dus needle that I have on 4th clip position the leak jet I have in there is stock #50 I found another jet on the carb I'm guessing it's the pilot air jet it's #80 I'll take a picture of where it is also I'm going to check my float height. The bike was running OK it was a bit poppy on decal with stock exhaust but I managed to take off ais then I fitted a fmf powercore 4 end can and it sort of bog out at top end when u wot to quick my starter motor broke so I took it all out to fit new one and thought I may as well do the carb at the same time

Do the O-ring mod to the AP pump linkage if you have a bog