Jump to content
Sign in to follow this  

drz400 sudco slant fcr jetting..again..

Recommended Posts

I have a 2009 drz400sm..

the carb is a Sudco fcr 39mm slant body for the drz400 model G30A0 WC16

3x3 and mrd/ssw full system

my elevation is 300-1100 ft

ave. temp 30-100

Jets:

152 main jet

45 pilot jet

(aslo have a 60 jet in the float bowl if you will.. believe it to be the SLOW JET?)

oc emm 4th clip from the bottom,

200 main air jet

1 turn on Pilot air screw

2 turns on fuel screw..

CURRENT PROBLEMS:

has poor idle, and dies and has a 20 second hanging idle.. all this happens either cold or after 20 minutes of riding..

i know it doesn't have any air leaks.. have checked with starter fluid..

i plan on doing the ap mod. including grinding of the diaphram. seems most over look..

and where should i buy needles and jets?

Share this post


Link to post
Share on other sites

I'd say your jetting is pretty close. The 60 jet is the starter jet.

Count needle clips from the top (4th is 4th either way) Main jet could be a little bigger, 158, 160

Close yo the adjustable air screw just a bit, 3/4, 7/8 turn open.

Open the mixture screw just a bit, say 2 1/2 truns. Should be close. Don't be afraid to play with settings record and track the results.

Share this post


Link to post
Share on other sites

it feels like it is leaning out on idle,, it pops pack throw the carb and dies.... should i change the starter jet? also should i change my needle to an emn 3rd clip?

edit: where should i buy the jets and needles?

Edited by mean-machines

Share this post


Link to post
Share on other sites

EMN needle is 1 step leaner than EMM on the low speed part of the needle. I would not change it. I would move the clip to -3 from the top.

Starter jet is only in play with the choke on - don't change it.

Main jets should be available from any motorcycle shop or SUDCO but they have min order size or TT store or mail order. Needles, TT store or any of the other sources.

Share this post


Link to post
Share on other sites

Needles (2) are propritary. There is a selection of main jets but I do not remember sizes. Email JD jetting.

Share this post


Link to post
Share on other sites

Needles and main jets wont help your issue. You need to get the pilot circuit tuned. Does it run well when on the throttle?

Share this post


Link to post
Share on other sites

the pilot air screw will fine tune your pilot circuit without the need to change pilot jet size in conjunction with the fuel screw setting.

if lean on idle, do as suggested and turn the fuel screw to 2 - 2.5 turns out & turn the PAS(pilot air screw) in a bit and re-test.

the PAS is a set-up that allows you to fine tune the air flow to the pilot circuit

instead of changing pilot jet size to achieve the correct fuel/air ratio.

nifty item IMO

Share this post


Link to post
Share on other sites

I would buy the jets from a local motorcycle dealer should you need them plus it doesn't matter what brand bikes they sell for the most part. You've only got 1 carb so it doesn't matter if they over charge you...it's a bigger deal if you're trying to tune a 4 cylinder and you're way off. Sometimes they'll let you swap for a couple bucks just like with shims.

Steve

Share this post


Link to post
Share on other sites

lol, i work at a dealership, sudco only does 200 dollar orders, and we didnt have 155,158,or 160.. and can only get them in packs of four from parts unlimited and wps... i just went ahead and called jd today and ordered a kit... i've owned 5 of their jet kits.. hope it performs as well as the other...

hopefully the kit will work with the slant fcr..

Share this post


Link to post
Share on other sites

lol, i work at a dealership, sudco only does 200 dollar orders, and we didnt have 155,158,or 160.. and can only get them in packs of four from parts unlimited and wps... i just went ahead and called jd today and ordered a kit... i've owned 5 of their jet kits.. hope it performs as well as the other...

hopefully the kit will work with the slant fcr..

I think your wasting your money, Noble gave you good advice in post #2 as you described a pilot circut problem.

No matter what needle you run it wont fix an idle issue.

I would up the main to #158-#160 and invest an R&D Flex Jet.

  • Like 1

Share this post


Link to post
Share on other sites

So I had to order 4 pilot jets but I got 4 48 pj coming and my jet kit will be here Monday so hopefully everything will go smooth

Share this post


Link to post
Share on other sites

Have you tried any of the suggestions given before you bought a jet kit an 4 pilot jets you probably will not need.

  • Like 1

Share this post


Link to post
Share on other sites

yes i did, all the adjustments with the pas, and the fs... i used a fuel air meter from work and i was still pretty lean on the low end.. i think it has to do with the fact my 3x3 is a litte larger than that.. and the only reason i strive to get it prefect is because i have several friends that arent believers in pumper carbs...

and i add 35 bucks off from jd jetting..

but i like to use my drz as a play toy, and a learning tool.

Share this post


Link to post
Share on other sites

OK. Still I find it odd you are lean and can't adjust it out with adjustable air screw and mixture screw. I did prefer a 48 pilot jet but that was with a fixed 100 air jet. You might be over looking something. Is the seal between the roller slide and the floating throtttle plate in good condition? Lip facingg out? And the floating plate in correctly? It can be assembled upside down and creates all kinds of problems. As the slide raises, you want air to come in the center, not the sides.

The size of the 3X3 is not going to affect idle.

Share this post


Link to post
Share on other sites

Well the carb has never been taking apart it and is only a year old. Seems to be sealed fine I tried to install the jd kit but have a horrible high idle 4500 I will try to clean everything tomorrow re use my emm needle increase pilot to a 48 2 turns out on the fuel screw 3/4 on the pas

Whhy would it idle so high?

Blue needle 165 mj 45 pj 2 fs, 3/4 pas

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

Reply with:

Sign in to follow this  

×
×
  • Create New...