What kind of Jet Kit is this and how do I adjust it?

Hi Guys

Any help would be appreciated, as I'm still a bit noobish :)

 

2005 400S converted to SM

I'm at ~550ft elevation. Ride 100% street.

Mikuni carb, K&N air filter, 3x3 airbox mod, just installed MRD/SSW corked.

Previous owner removed baffle on stock exhaust and said the carb has been re jetted (no idea what kit).

Bike run mostly fine untill MRD.

 

After installing MRD, bike started backfiring a bit when decelerating, it pops when I up shift, it died a couple of times when taking off in 1st gear from full stop.

Still need choke pulled to start when cold (like with stock exhaust).

 

Should I tighten the header more (it's on pretty tight), or maybe replace the crush gasket? (I reused the old one as it looked good)

 

Should I get rid of TPS as well? I think I've read somewhere that it's the cause of a flat spot in higher RPM? which I have.

 

Also, should I switch to foam filter instead of K&N? Some say foam breaths better.

 

Airbox, took the filter out to clean it, should I reapply some grease when reinstalling? Or just clean it up?

 

IMG_1256_zpsbfd452ab.jpg

 

IMG_1261_zps5ce1e026.jpg

 

IMG_1263_zps996b5d9f.jpg

 

IMG_1272_zpsa5495cbb.jpg

 

IMG_1267_zps5f37843d.jpg

 

IMG_1275_zpseccb0d71.jpg

 

What Kit needle is that?

The clip is on 3 slot.

Any other needles/jets I should look at?

 

Thanks guys!

Edited by no1_cdn

What size main jet is in it?

I'm assuming pilot is stock?

What size main jet is in it?

I'm assuming pilot is stock?

 

:confused:

 

Hi OhioYJ

 

How would I go about finding that?

I tried looking for a manual on JD Jetting and Dynojets pages but no luck...

 

How do I find the pilot and main jets?

 

Thanks

OK

Found video on YouTube :D

 

Jets are:

155

62.5

25

 

IMG_1280_zpsd424dccd.jpg

 

IMG_1284_zps5743fce9.jpg

 

IMG_1283_zps72f55039.jpg

 

Side question, what is this rubber dipped, bent metal tab on this screw?

Do I need it? I don't think it was holding anything?...

 

IMG_1278_zps53699645.jpg

 

Thanks

 

OK

Located JD Jetting manual.

I think this might be the kit that the previous owner installed, since the clip is in 3rd slot and, I think, there's a blue(ish) smudge on top of the needle.

 

JDJetting01_zps478a8926.jpg

 

For some reason I have an extra washer on my needle...

I have:

thin washer

clip

plastic spacer

thick washer

thin washer

 

Manual states (as in pic above):

thin washer

clip

plastic spacer

thick washer

 

Should I remove that extra thin washer?

Why is it there?

 

 

Also the manual recommends to install #160 main jet with more free flowing exhaust:

Would that fix the issues I listed in first post?

 

JDJetting02_zps99c60ba5.jpg

 

Thanks

 

use clip 4 and the 155 main jet with the corked MRD, (160mj with open pipe)

 needle spacers as per manual

popping on decel is normal for a correctly tuned pilot circuit...

use a 22.5 (stock) pilot jet with an extended fuel screw or a 25 pilot jet with the stock fuel screw..

2.75 turns

Edited by Craigo 485sm

use clip 4 and the 155 main jet with the corked MRD, (160mj with open pipe)

 needle spacers as per manual

popping on decel is normal for a correctly tuned pilot circuit...

use a 22.5 (stock) pilot jet with an extended fuel screw or a 25 pilot jet with the stock fuel screw..

2.75 turns

 

Hi Craigo

Thanks for your suggestions!

I don't have stock pilot jet or extended fuel screw, I bought the bike already jetted.

I'll remove the extra washer and adjust stock fuel screw, then report back.

The carb is dirty. Can see the goo in the pics. Get some carb cleaner and clean the whole carb and flush all the jet channels with it too before reassembly. Still has the stock fuel screw in it. May affect how it tunes up. While apart check the float needle for grooving on the little rubber tip. Cant hurt...

Edited by Jim BurnCycle Abbott

 

 

 

 

 

 

Side question, what is this rubber dipped, bent metal tab on this screw?

Do I need it? I don't think it was holding anything?...

 

IMG_1278_zps53699645.jpg

 

Thanks

 

I believe the plastic coated clip is used to hold a vent line.

use clip 4 and the 155 main jet with the corked MRD, (160mj with open pipe)

 needle spacers as per manual

popping on decel is normal for a correctly tuned pilot circuit...

use a 22.5 (stock) pilot jet with an extended fuel screw or a 25 pilot jet with the stock fuel screw..

2.75 turns

 

Hi Craigo

Thanks for your suggestions!

I don't have stock pilot jet or extended fuel screw, I bought the bike already jetted.

I'll remove the extra washer and adjust stock fuel screw, then report back.

 

The carb is dirty. Can see the goo in the pics. Get some carb cleaner and clean the whole carb and flush all the jet channels with it too before reassembly. Still has the stock fuel screw in it. May affect how it tunes up. While apart check the float needle for grooving on the little rubber tip. Cant hurt...

 

I believe the plastic coated clip is used to hold a vent line.

 

OK

I tightened the header a bit more, removed the extra washer, adjusted fuel screw to 2.75 turns, but left the needle clip on 3rd slot.

Popping on decel is greatly reduced, also when up shifting, only occasionally now...hasn't stalled on me yet either.

I dunno if it's me, but the bike feels like it's running a bit better too, pulls stronger? Except for the flat spot (or hesitation) when accelarating

at around maybe 1/3 open throttle. Most pronounced in 3rd and 4th gears.

Funny thing, that hesitation/flat spot was almost gone when I first rode the bike after putting the carb back in. Then on my second ride, a few hours later,

it came back :(

 

Is it the TPS, the needle or maybe the fuel screw?

Maybe I'll try clip in 4th slot, like Craigo suggested...

 

I did clean the carb, thanks Jim, forgot to check the float needle though... :banghead:

 

npm, I think you're right. I ended up removing it as there was no need for it.

 

Thanks again guys!

Hey

Put clip on 4th slot, bike feels better.

It started popping a bit more on deceleration.

Flat spot (or hesitation) when accelerating at low throttle is much reduced! Thanks Craigo :thumbsup:

Is there a way to eliminate it completely?

 

Thanks

Hey

Put clip on 4th slot, bike feels better.

It started popping a bit more on deceleration.

Flat spot (or hesitation) when accelerating at low throttle is much reduced! Thanks Craigo :thumbsup:

Is there a way to eliminate it completely?

 

Thanks

 

Try running it without the insert....often a cork in a race pipe will cause some hesitation, but that's usually when you have an Fcr...

Try running it without the insert....often a cork in a race pipe will cause some hesitation, but that's usually when you have an Fcr...

 

Hey

OK, I think I got it solved, finally! :D

 

I'm using 5th slot on needle! and 2.5 turns out= Almost no popping on deceleration (Very rare) and no popping on upshifting at all! Also no flat spots/hesitation while cruising!  :banana:

With clip in 5th slot and 2.75 turns out, I had zero popping on decel. and upshifting, also no flat spots while cruising, but I felt it might be running a bit rich... so I adjusted screw to 2.5

 

Just to recap my setup:

Stock carb (Mikuni)

K&N filter

3x3

MRD/SSW with decibel killer

JD Jetting

Blue Needle

5th clip down

155 main jet

62.5 starter jet

25 pilot jet

Stock air/fuel screw

2.50 turns out

 

Hey

OK, I think I got it solved, finally! :D

 

I'm using 5th slot on needle! and 2.5 turns out= Almost no popping on deceleration (Very rare) and no popping on upshifting at all! Also no flat spots/hesitation while cruising!  :banana:

With clip in 5th slot and 2.75 turns out, I had zero popping on decel. and upshifting, also no flat spots while cruising, but I felt it might be running a bit rich... so I adjusted screw to 2.5

 

Just to recap my setup:

Stock carb (Mikuni)

K&N filter

3x3

MRD/SSW with decibel killer

JD Jetting

Blue Needle

5th clip down

155 main jet

62.5 starter jet

25 pilot jet

Stock air/fuel screw

2.50 turns out

 

 

That's good to hear.....Is your 3x3 larger than 3"x 3" ?.as your needle setting is is richer than the usual..

That's good to hear.....Is your 3x3 larger than 3"x 3" ?.as your needle setting is is richer than the usual..

 

Thanks Craigo

3x3 is very close to 3"x3"...

I had more time to ride it today and it was much warmer than yesterday and now I'm wondering whether it's too rich :D

Yesterday was quite cold and it rained so humidity was up... maybe that's why it run perfect...

 

Well, today was nice, dry and sunny. So after like half hour of riding the bike died on me, it'd start and idle OK but any amount of open throttle would kill it.

I started to think that I made it too rich!

I limped it home, took apart the carb and saw that the plug that holds the small spring to the needle got loose and was just laying there.

 

IMG_1267_zps5f37843d.jpg

 

As soon as I reinstalled it and put it back together it was fine.

I turned the screw down to 2 turns out, just in case... It pops more now but still no flat spots :)

 

Would that plug get loose if the bike was running too rich?

Or was it me, not installing it correctly? I'm pretty sure I heard it make that click sound when it's sat correctly inside the boot...

 

Looks like I need more tuning still.... and I thought I was finally done! LOL

 

Or was it me, not installing it correctly?

 

I sink so..... :smashpc:  :naughty:  :smirk:  :bonk:  :shocked:  :doh:

I sink so..... :smashpc:  :naughty:  :smirk:  :bonk:  :shocked:  :doh:

 

Live and learn :D

Did more testing today, I think that perfect feeling I had the other day was really bike running too rich...

I played with the fuel screw and the needle and it feels either too rich or too lean...

I'm gonna get that 160 main jet and see if that helps eliminate the flat spots.

Engine response to throttle should feel smooth when too rich.

 

What does 'too lean' feel like to you? Popping in the intake?

 

I run the stock 142.5 at 1000', but I'm also using a 25PJ and a DJ needle. My engine responds very nicely to any throttle increase.

Edited by shuswap1

Engine response to throttle should feel smooth when too rich.

 

What does 'too lean' feel like to you? Popping in the intake?

 

I run the stock 142.5 at 1000', but I'm also using a 25PJ and a DJ needle. My engine responds very nicely to any throttle increase.

 

Hi shuswap

From my understanding DynoJet uses diff. needle numbers vs. JDJetting, I'm not sure what your 142.5 be equivalent to on mine...

 

Too lean (3rd clip, 2.5-2.75 turns out) A lot of popping while decelerating, upshifting, flat spots while accelerating or cruising.

Less lean (4th clip, 2.5-2.75 turns out) popping while decelerating, upshifting, flat spots while accelerating or cruising. All were reduced by half, I'd say, vs. 3rd clip on needle.

Also tried this trick:

"After the bike is good and warmed up, pull the air box cover and go for a short spin. If it runs better you are rich, if it runs worse you are lean. Then you can adjust accordingly."

With clip in 3rd and 4th and various fuel screw positions, bike run worse without air box cover = lean.

 

When bike was too rich (5th clip, 2.0-2.75 turns out) there was zero popping while decelerating, upshifting, no flat spots while accelerating or cruising. Also, sometimes, I could smell gasoline at idle.

 

Don't care for popping anymore (but it's obviously affected by fuel richness), but i gotta get rid of the flat spots/bog down, like its not getting enough fuel while accelerating or cruising.

 

I'm gonna change the MJ and possibly the air filter and report back.

My 142.5 is the OEM stock MJ, which I found to work nicely. I think you're right, the numbers don't relate to one another if you are using JD MJs. Mine pops heartily on decel.

 

The DJ kit was installed by the original owner, but he only used the needle and the spring, leaving a pile of DJ parts sitting in the kit. I've played around some with the other jets and would have to agree with the PO's approach.

 

The only change I made was to install a 25PJ, mostly in the hope this would smooth the transition off idle when riding tight stuff. I think it was helpful in that regard.

 

Ooops, I have the keintech as well, but I really don't seem to need to touch it while riding from 1,000' to 7,000'. Go figure?

 

In my experience, when it's going kinda sideways, get back to the starting point, working there and then proceed with one change at a time. I've only ridden 2 other DRZs, but neither ran as nicely as mine does, from off-idle to top end

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