Jump to content
Sign in to follow this  

Anyone have issues with JD jet kit and 2011 450SXF ?

Recommended Posts

My friend (who is not a computer guy) has a 2011 450SXF , he recently put a Pro Circuit pipe on it , he also tried a Dr.D , and both gave the same issue , the bike was/is obviously lean , and became very difficult to start , put the stock pipe back on (all are full systems) and the bike starts right up , he purchased a JD Jet Kit , and used the jets they recommend for this altitude (approx 500+ ft Above Sea Level) , it recommended the stock 42 pilot , and a the stock 182 main and the needle change , the bike is so hard to start it usually kills the battery cranking it so many attempts to TRY to get it started (no kick start), fuel is fresh and a mix of Premium and Av gas (which i would think the Av gas would lean it out some) , as the pipe change came so did a drop in temps , our average ride temp is 45 degrees F or colder

as a side note: with the recommended #42/182 the entire header pipe glowed bright red from the minute it started till it was shut off 1 minute later , this was all the way to the mid pipe joint which is at the frame where the footpegs are , so that is quite a distance for it to glow , it also shot flames out the muffler on every decell

I have 2 Honda's , a 02 CRF450R and a 06 CRF450X , both i have jetted myself to work in this elevation , both my bikes start right up , my R cold will usually start on the 2nd kick , sometimes the 1st kick , my R has the same size 41mm carb the KTM has (02 was the only year to have a 41mm all other years have 40mm) ,both my bikes are jetted as follows

Elevation: 500-1500 ft

450R:

Pilot: 48

Main: 180

Needle: stock 4th clip

Leak Jet: stock 70

Fuel Screw: 2 3/4 turns

450X:

Pilot: 48

Main:178

Needle:stock 4th clip

Leak Jet: 65

Fuel Screw: 3 turns

His Bike:

Pilot:45 .....(going up from the 42 helped but did not cure the starting issue)

Main: 185 .....(going to the 185 , from the 182 helped but did not cure the starting issues)

Needle: JD Red ......(i think it was Red , it was the recommended cold weather needle)4th clip

Leak Jet:..... R&D Power Bowl w/Adj. Leak Jet set to approx 45 (recommended by R&D)

Fuel Screw: .....we have gone from 1 1/2 to 3 1/2 , with no difference in ease of starting , currently at 2 1/2 turns

We have a 45 pilot in it right now , which is higher than JD recommends as well as a main at 185 that is higher , and its getting better , Pro Circuit nor Dr.D gave any jetting recommendations with their systems , and you have to hold the throttle open with the choke on in order for it to attempt to start (pumping the throttle does not make it start easier, and YES the AP is working and has the mods done to it as per JD and R&D recommendations*springs ,etc*) , should we have to go to a 48 like my bikes are ?? , as right now we are already richer than JD recommends on both pilot and main , for $80 you would think the bike would have started better , it starts the same as it did once the pipes were changed because the recommended jetting is the same as stock which seems wrong for a aftermarket complete system

My bikes start fine in 80+ temps as well as the current 35-50 degree temps with the current jetting

Anyone have a 11 450SXF at this elevation that could recommend a jetting that will allow the bike to start like it used to with stock pipe/jetting ? , as we are stumped as we did not think we would have to go that much richer than stock with just the pipe change , and as i said , it does it with both pipes , but will start right up with the stock pipe back on

He has spent over $350 in jetting crap *bowl and jet kit* and the bike still will not start easily , also the bike has only about 20 hours on it total , and like i mentioned , put the stock pipe back on and it starts right up

Share this post


Link to post
Share on other sites
I run lean needle in my 11s,follow kit to a t,western pa ,

~800-1000' elevation ,may tweak fuel screw,stock exhaust,runs perfect!

That's the red needle, correct?

Share this post


Link to post
Share on other sites

Just remember that if you are near 3 out on the fuel screw go up on the pilot so the fuel screw won't become loose. This is strange. Perhaps go bigger on the pilot. Almost sounds like an air leak. let us know

Share this post


Link to post
Share on other sites

That is the issue that bugs us , all we know is the pipes are the issue , as soon as the stock pipe is back on the bike starts right up , i cant hear and leak , cant see anything out of the ordinary , we even sprayed the pipe with WD-40 while running (right when it first started before the pipe got real hot) at the joints to see if it changed anything , nothing changed , as far as RPM or anything that would indicate a leak , the stock system is titanium , the aftermarkets are both Stainless , though that should not matter with anything but weight , he is waiting for the 48 pilot to come in at the KTM shop , but that is about our only hope , all indications are pointing to lean , but as i stated , JD recommends STOCK jetting for this altitude and with the richer jetting currently in the bike the pipe is gray *soot* not black , with the stock/recommended jetting it was white , which would indicate lean , as well as the constant backfiring it did with the recommended jetting , i found that both my bikes are richer than what is recommended for this altitude , so again , all i know is richer made my bikes run (i came from 2300-8500 ft riding with 45/170 *R* and 45/160*X*) , so maybe the air density has something to do with it besides elevation ?? , i just dont really know , that is why i was trying to find out if anyone with a 11 450SXF in particular with a pipe at this elevation had similar issues trying to get the bike to run properly after adding the pipe,, all i know is nothing we have tried has cured the issue , only helped slightly , but nothing dramatic

Share this post


Link to post
Share on other sites

Get in touch with James directly, chances are a bigger pilot will cure it considering everything runs well with the std pipe. You have to remember his recomended settings are for a stock setup and it appears on this bike aftermarket pipes need jetting tweeks from his baseline to account for their flow differences

Share this post


Link to post
Share on other sites

Yea , that might be the best thing to do , since we are getting no where on our own , you wouldn't think it would be that difficult to get it to start , once it runs its ok (sort of) , but the starting issue is what the main challenge is , as every time when its cold it will almost be a guarantee it will wear the battery down , even the new Shorai battery

I will give them a call tomorrow and see if they have any suggestions

Thanks for the help !

Share this post


Link to post
Share on other sites

Well I talked to James Dean , and he suggested a few things , i tried them with no success , then when we got talking about my CRF450R , so he said that the Honda has a different size Start Jet , than KTM and if my bike started right up with about the same jetting as the KTM but the KTM wouldnt start (remember this is ONLY when COLD , when warmed up the bike will fire every time) then it might have something to do with the Start Jet , so i pulled the start jet out of my 450X and the bike pretty much starts right up now , so what we ended up with , in case anyone else has this issue , is

Pilot: 48

Main Jet: 185

Needle: JD Blue 3rd clip

R&D Bowl Adjustable Leak Jet , set to approx 75(1 1/2 turns out)

Fuel Screw : 2 1/2 out

Start Jet:(this is the 3rd jet you see when you look in the bottom of the carb) , main, pilot , Start Jet *it is the short stubby jet* , it will most likely be #85 ,KTM does not list other jets sizes for it , i replaced it with a #70 from my Honda, this jet is only used when starting the bike (with the choke only i believe) , but a Yamaha jet will suffice as well , as the jets from all the 450's with FCR carb will interchange , so if KTM does not have any jet you need , do not hesitate to go to a Honda or Yamaha ,Kawasaki , Suzuki Dealer to get jets

Share this post


Link to post
Share on other sites

Adding to 450XjimDirt findings:

 

I have also have a 2011 450sxf  with the JD kit, and yea jetting for cold starting is hard.

 

Today is cold, at 43F/4c. I'm at 250ft above sea level and I'm running stock header with an after market muffler.

 

In summer,  I have good luck with the above recommendation, a #48 pilot, and #70 starter jet, but today I moved down to a #68 starter jet and it worked much better.  Stock is  #42 pilot and #85 starter jet.  What is happening is the richer pilot is effecting the start jet, so in order to have good warm-running idle/starting, you need that rich pilot, but with that, for good choke starting you need a much leaner starter jet.

 

Cold weather starting:

Pilot jet: 48

Starter jet: 68

Fuel screw:  2 1/4 turns out

Stone cold starting method: Choke on, one throttle twist, wait 5 seconds, zero throttle, hit start button.

Edited by speedbump49

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×