All 2st Jetting Chat - Need Help? Post Your Questions Here

That sounds just about perfect. I wouldn't bother with the JD blue needle unless you're riding in really cold conditions or something, it's richer than red.

I am currently running a very similar setup as Glenn (45 pilot, 172 main, DEL in 4th clip). FMF pipe, stock silencer, sea level. Before that I was running a 42 pilot, 172 main, JD red in 3rd clip for spring/fall and 2nd clip for hot summer days or more elevation (1k-2k).

Your main might be richer than it needs to be but it won't hurt anything. You ought to be pretty darn good. If you're unhappy you can try the DEL needle, I like it a bit more than the JD red but honestly the red was fine for me too.

Thanks guys. Yeah, I am going to bump down on the main to a 172. Its a smidge fat on top. I thought it felt ok. But coming from 5000ft to 500ft, I just basically went off stock jetting for a ktm 300 (same carb) and a little guesswork.

Kyle, you were running the red needle too at low elevation? No issues and motor in good shape internally still? That's really all i care about. It was running good, but you never know what's going on inside. If its good w red on 3rd clip down then I am golden. My bike has always run better on the lean side vs rich side.

Yeah, I started with the blue when I first got the PWK, but I talked to JD and went to the red pretty early on and never went back to the blue. I think I had the red in for a solid year, probably nearly 100 hours, no problems that I can tell. I tried red on the first clip once and it was definitely too lean.

Edit: I am at sea level, yeah. Half of the events I race are probably at about 20 feet of elevation, the other half are probably 1,000 feet or so.

Hey guys. I would like an advice. What needle would you recommend for the WR300 with stock Mikuni carb at around 20degrees Celsius for a Clean smooth bottom end, riding in gnarly terrain? my son has this bike and it smokes and bludders too much with the GAY needle in 3rd/4th clip. I have a Wr300 2012 myself but have been using the PWK for some years on these bikes and have forgotten what could suit the Mikuni in the summer .

Johnny

Welcome to the PNW marcomo. Those settings seem about right for this time of year. I ride the Tahuya area, which is about an hour or so from auburn (towards Bremerton). I'm running a 42 pj, 1.5 as, red needle at 3rd clip, and 178 mj on my '11 wr 300 with high comp head, stock exhaust, pwk as 38, 50:1. Seems to run pretty well with these settings. We should hook up soon and I can show you around Tahuya. Look it up on the Washington department of natural resources web site. Lots of single and two track trails with a few gravel roads to connect everything.

Thanks Brian! Great to hear I am close on the jetting. I actually went out to Tahuya a few weeks ago. Super fun. Went out and rode about 44mi. Got a little turned around but made my way back to the truck. I'd love to hang and ride soon. My pipe is at PC pipe repair, but if it gets back in time I'd love to get out next weekend. I will drop you a line if it gets here later in the week.

hi guys. I recently bought my first proper dirt bike which is a 02 husky cr250. I am extremely happy with everything exept for one thing, comsumption. I am assuming its rich jetting fault but i cant find good instruccions on how to set up the mikuni tmx. And its a big issue because i have to ride to the track which is in the middle of an enduro paradise.... so its far...

any help from someone who has experienced the same issue will be apretiated

the carb on my bike is not the squared old looking one, its the round one. I dont know if it makes a difference.

I posted some pics of the bike and terrain here:
http://www.thumpertalk.com/topic/1089974-husky-consumption/#entry11675244

Any idea for wr 125 tmx 38 carb. Power valves. I want to get more bottom end
The bike has 2500 km and runs in 500 meters. I have the stock adjusting i have never change anything

So I recently just put the 165 top on my bike (09 WR125). It rips, love it. Went to pull the carb (Mikuni TMXX) apart because I love taking shit apart and putting it back together. Plus, I wanted to do a proper plug chop on the new top end so I can get the ole' girl running perfect. My biggest problem is hard to describe but basically, once I pull into my mid to upper throttle range, it feels like the bike is just almost "coughing" a bit, almost as if I just hit it hard a few times it'll clear out and go (which doesn't happen). It will build up to power, but it sometimes feels like it has a hard time getting there. It was that way in the lower end, too, then I put in a bigger pilot. Here's my spec's:

Elevation: tested at ~800-900' ride at 800'-2000'
Pilot jet: Originally 40, changed to 45
Main jet: Originally 400, tried 410, then to 450
Needle: RM needle, not sure what clip because I can't figure out how to get the throttle cable out of the slide! (help!)
Plugs: NGK BR9EG
Fuel: Pump 93 (ethanol free) with 44:1 Spectro mix.

I did a plug chop with the 45 pilot and 410 main. I warmed up the bike on the old plug. I had about a 1/2 mile strip, so once warm, I put the new plug in, opened the bike WFO, ran though all the gears and held at the highest one for a few seconds and hit the kill switch. Pulled the plug, the thing is basically white. Hardly looks used, maybe a little black tinge, but essentially white. Put the 450 in, same test, same results. I saw no difference in my plug chop between the 410 and 450, and am wondering what I'm doing wrong in my test because I can't imagine my bike is that lean. I did notice a considerably larger amount of "spooge" coming out of my silencer.

So, am I doing the plug chop wrong or am I that impossibly lean? Seems like I'm running a larger Pilot than most and a smaller main.

My background is in automotive performance, and nobody there has done plug chops for 20 or more years. With modern fuels, they don't tell you anything, unless you're so lean you're detonating.

Anyway, unless you have an air leak somewhere, you're rich. I have the same bike, at the same elevation, with
30 P
450 M
RM needle with #5 slide (you MUST run the #5 slide with the RM needle or you'll be crazy rich)

The cable slips into a slot on the needle retainer. You need to loosen or pull the cable out at the throttle to allow some slack. Lift the spring out of the way, then push the cable down, then sideways out of the slot.

We're heading to Butte in a week for Evel Kneivel Days. I'm hauling my Husky & my son's KX60. Elevation starts at 5500' & I expect the temps will be about 80*. I switched the KX main jet from a 200 down to 185.

I bought a JD kit for my Husky, I installed a 400 main jet & the white needle on the 4th clip. I looked in the jetting data base here & didn't see anyone with a WR300 using the white needle, I'll give JD a call Monday to confirm I'm using the right jet & needle. I use Maxima Super M & 92 octane. I'll dial in the air ratio after I get there.

We won't be flogging our rides, I nearly broke my wrist in a bicycle crash 3 weeks ago & my son is still learning to ride the KX, so our pace will be pretty mellow for the 3 or 4 days we will ride. I'm not super concerned with getting max performance this trip, I just don't want anything to get damaged.

I plan to go with the red needle & a 420 main jet when I get back. I hope this helps with the splooge. Any thought are appreciated.

Hey guys,
As I am breaking in new top end and fully warming the bike up now, I do notice that it's somewhat slower than my new beta.
Pipe is good and Powervalve is clean an opens (checked by removing cover off and revving bike) bike starts first kick, which is awesome for WR 300... But mid and top end feel somewhat flat comparing to beta. Rekluse is removed, stock carb.
Of idle, throttle response seems nice. No hesitation. And playing with air screw made it harder to start so I am back to 1-3/4 out.

Any suggestions?

Settings are as following.
Main 430
Pilot 45
Slide 4
Clip 2 from top
Needle:6BFY43-74 2nd from UP

Jetting wr 125 model 2013 new 600 km
I started with main 460 needle rm 16-62 ( clip in middle position) pilot 45
oil is now the motul 800 at 2%
Lots off smoke, spooge and a black plug when not ridden throatle wide open. ( wide open plug color is ok )
Then I changed my pilot to 42,5 40 and now 37,5
The bike still starts without choke and still spooges a lot. Smoke is a liitle better.
Then I changed the needle to 16-63 ( mid a bit leaner) This how I ride at the moment.
I marked my throatle in 1/4. 1/2 3/4 so I can see and feel what the bike does.
At first when riding on the road in six gear with the throatle at the 1/4 I had the engine four stroking a lot. Since I changed to the 37,5 pilot it is steady in sound/feel
Now when I am in second gear it doesn't stall when idling, when I slowly open the throatle an let the rpm go up everything goes fine, but when I suddenly open the throatle 3/4 or full it goes maahhhh, Is this a lean mixture indication?
Should I lower the clip on the needle or go back to the 16-62 ? bigger main jet ?
When going through the gears the bike really pulls hard, maybe I feel a small hesistation when in higher gears.

Another question:
When playing with the airscrew I get max rpm at 3,5 turns out . Is this indicating pilot is still to large ?(37,5 now)
Plug looks rather black when checked at the 1/4 throatle position.
When going leaner on the pilot will this also make the 1/2 and 3/4 leaner. ( I think I cant go leaner at those setting)
When the bike is idling at the side stand it's got a higher rpm then when I keep it perfectly straight. When straight the idle goes down in rpm.
The idling screw is almost completely in for setting the idle. (was completely in with the 42,5 and 45 pilot)

What to do next?
Thanks,
David

When I used Motul 800 no matter how well the bike was jetted the thing smoked pretty bad and spooged worse than any oil I have ever tried ! Could not wait to use the bottle up, Oh and anyone following me always complained about the smell and how it gave them headaches.

David Bergen,
It sounds like you are still too rich on the pilot. Leaning it will only effect the 0-1/4 throttle. Don't be afraid to try leaning it out further. You need to get the pilot in the right neighborhood before you can dial in the needle type and clip position.

yesterday It took me almost 4 hours jetting and I still have the problem when suddenly opening the gas 1/2 till full.
This is not happening when I go through the gears only when at low speed in a higher gear. Like riding in second gear ( speed 10 km/h and suddenly opening the throatle full) It goes maaahhhhh till it dies. Closing the throatle has it going again.
I tied every combination to get this away.
Changed main from 460 to 470
Tried the fattest needle 16-62 at the lowest clip position. It definately changed throatle respons 0- 1/4 ond I got a black spark plug. This part was again too rich when it was four stroking again on continious load. 1/4 throatle
After that I tried it with my leanest needle 15-74 . 0-1/4 was better again but wacking the throatle open and I got the maahh... again. Worse than the fat needle.
Now I changed the throatle valve from nr 5 to a nr 4 but It didn't change a thing
The jetting I finally setteld on is slide nr 4 main 470 pilot 40 and needle 16-63 second slot from the top.
This is crisp at the 0-1/4 and goes crazy at the high rpm but still does the same when suddenly opening the throatle when the engine is having low rpm or in higher gear.

I'm not sure if this applies but there is some threads about this bog that were solved by using a Suzuki RM needle and different slide but since that is is fairly expensive compounded with the sack of jets you have to buy to get it sorted most riders now buy a Lectron or a Keihn and call it done.

I bought the Lectron for my WR250 after I sorted the Mukini and I still consider it money well spent. In hindsight I wish I would have never spent a dime or a minute on the Mikuni.

David, I'd suggest getting the pilot right first. You mentioned having airscrew 3&1/2 turns out with 37.5 pilot to get best idle, that indicates the pilot is too big still. For reference, I have the same model as you and have ended at 17.5 pilot with a/screw 1&3/4 turns out. You may not end up at this setting but it indicates how rich they can come from the factory. Once you've got this right move to the needle.
The maaahhhhh you describe sounds like a lean needle setting and as you mentioned it was even worse with the leaner needle. Have you tried the 16-63 with the clip at its lowest ( richest ) setting? Again I have mine set at this position. Just to be sure the clip positions are referred to with the needle held so the grooves for the clip are on top (the needle sitting on its point).
I hope you find this helpful as the little WR should be enjoyed, it has good engine performance and handles like it's wired direct to your brain.

Hi all,

My first post on the forum, and there will be more :-) .
Few months ago i bought an wr250/2003, did not go well.
So put in new piston, cleaned powervalve. This was mounted @husqvarna dealer as cilinder was there to get honed.
Powervalve was rebuild withe new bearings so i assume ot is in good workin order.
Engine runs great and has enough power, only when @ low rpms and you go to Wot it is sluggish until a certain rpm and then it launches.
Already leant it down to 35pilot, 190main, 61needle with clip in second from top, #3slide. Airscrew 1,5 to 1,7 turns out.
Sprockets are 13/48.
Before it had 40 pilot with 60 needle and had spooge coming from the exhaust.
Have bben riding @ sea level and around 20*c.

Greetings

Do you have the Mikuni TMX carb? If so I would think your main jet should be more like a 390! How does your spark plug look?