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

Glad u got it fixed!

Yeah, but I made a fool of myself on TV and Youtube. Oh, well.

Don't feel so bad. I for one, wish I was riding at the level for the opportunity to make such a fool of myself on national TV....

Steve-oh chiming in here. I'm new to Husky Cafe. But I have been lurking on this site and dreaming of the day when I can buy a new Husky. Well reading the forums and all the good things about the WR300's I finallly bought one A brand new 2010. Today was the jetting day. The carb has been set up quite rich from the get go, smoke and tons of spooge. Normal for factory settings as I've read here on HC.
Heres the results.

Mikuni TMX 38, stock carb.
3000 feet elevation.
40:1 Amsoil Dominator, 91 octane.

Factory settings as follows...
430 main
45 pilot
GAY needle, #3 or middle setting for the clip.
Mixture screw at 1.5 turns out.
Runs like shiet. Won't idle.

Adjustments as follows

420 main
40 pilot
GAY needle, #2 setting of the clip, second down from the top (leaner)
Mixture screw at 2 turns out

Runs much cleaner, idles great, gets into the power band very quickly. I've only rode it on some farm roads so far. I will have a better feel for it once we get to the Rockys.. first impressions.. quick and planted. I really want to see how this bike lugs thru the tight single track we ride and the traction it has. I'm also curious about the Keihin PWK carbs for possibly smoothing out the power curve and gaining some power off the bottom end.

Cheers
Steve-oh

hello Steve-oh and congratulations to a great bike=)! If you decide to stay with the Mikuni carb i can recommend you to use a needle named 6DEY15-74. Tried and tested! My bike ran much cleaner with this needle compared to the "GAY"-needle.

Johnny

Thanks Johnny

What carb are you running now on your 300? Also did you shave your cylinder head to increase the squish and raise the compression? if so how much did you shave off? I talked to a local Husky dealer and he doesn't believe there is any need to go to the Keihin carb. However he says the race head is a good mod.

Steve

Hello again!
I,m using the Keihin PWK 38mm Airstriker. It,s a BIG improvement. The bottom end is much stronger. A dynorun that HRC 630 here at the forum did on his 300 showed a big increase in bottom end power compared to the Mikuni. It is much easier to jet and it,s not so sensitive to weatherchanges as the Mikuni. Starts easier too. You will loose a little top end power, but not much. Motosportz here at the forum sells them with JD jetting needles. Very good!

No, i haven,t shaved my head. I use the Husqvarna high comp head, and that is also a very good improvement. I used that for iceracing this winther and it really made the bike stronger, but as i bought a Honda CR 500 for that this year i removed the racehead on the Husky because it got too abrupt for woods riding for me. I don,t recommend that head for gnarly terrain where you need a smooth power delivery. Everything depends on how you use your bike=)!

Regards
Johnny

Good info Johnny, our riding is tight single track, forest, rocky, rooty, muddy, big hills, rarely do you get out of 3rd gear. Sounds like the racehead may not be well suited for this type of riding, although I do love power I'll give the Mikuni a shot, if I don't like it out it goes and in with the PWK.

Steve

Sounds like were very close with jetting on the 36 pwk. My cr runs perfect with this setup:
172
45
N7NW #3 (99' kx125 needle)

This carb was the answer for my bike. It runs absolutely fantastic and pulls harder than I thought a stock 125 ever could.
I can cleanly make the 5-6 shift with this carb too... something the 38 Mikuni just could not seem to do regardless of jetting.

Hi Guys,
I've just purchased a 2010 wr300 brand new. I've been through 2 top ends in a week ! I ride mostly desert and both time it has seized at full throttle after about 3-4hr riding. I'm gonna give the Kehin PWK 38 airstriker carb a go, can you tell me where you get them from as the link on the Motosportz Superstore site does not seem to be working.

No matter what carb you use, I think you should spend some time jetting it correctly, but you already knew that.
I usually send MS a email when I order: motosportz@gmail.com

Your carb must be set up pretty lean on the main jet I would suspect. What # is your main, I'm at 3000 feet and using a 420 main.

I would bet that your dealer never changed the crazy lean factory set-up. Change your jets before you burn up another!

Steve, I disagree slightly with JohnnyMannen about the race head. I have one on my wr300 which I ride always in woods tight technical terrain. The increase in compression really improves low down pull and mid range. As you know even with the std head these motors have a lot of low down torque almost 4stroke like, with the race head it is improved even more. I think the term 'race head' leads people to think it is for wot and top end, infact there is less difference at high rpms than lower down. For the cost of the head $120 ish it is a great improvement.

"windsurf" thanks for the input. Wow only 120 for a head, I'll be checking that out at out local Husky dealer. What carb are you running?. My Mikuni is set up pretty good but I have nothing to compare it to. Most people say the Keihin carb gives them more low end power so with the race head and a new carb I think that might be the ticket for the woods. I'm not afraid of more hit or more power. I've been riding a pretty heavily modded RM250 for years. The reason I'm getting away from the RM is it just doesn't feel planted in the rocky rooty stuff. The one feature I do like on the RM is the Dynaring so I'm in the market for an autoclutch for the WR.

The part number is HO944 I bought mine from Huskysport in the UK as it is difficult and expensive to buy anything here in Oz. I know you can get them in the US so I would guess your local Alberta dealer can get them. I have done the carb change and use the Kehein which as everyone tells you is easier to jet and improves starting etc. I guess you could have the std head machined to improve squish and raise the compression as the race head, but it was easier and probably cheaper for me just to buy the head. I would say if you buy a new head it would be worthwhile also ordering the two water outlets as they are very tight in the head and tend to mangle as you take them out.

The bike came standard with a 45 pilot and 440 main, the neelde in middle clip position. I live on the coast so you would expect to run richer jetting than standard. I geared the bike up and was running 14/45. I did a plug chop with that gearing and it was a little leaner than I would normally run but still fine, it seized on the next ride. I then went and put a brand new cylinder and piston assy on and re jeted the carb as follows, moved the needle clip down one position to the 2nd from bottom and went to a 460 main. Bike ran fine for about 2 and 1/2 hrs then did exzactly the same thing! I've jumped of a 2010 yz250 and never had dramas like this! I've spoken to Husky Australia and they are saying that I should have a piston clearance of .003" sound a bit tight to me?? any idea's. I did manage to get onto Motospotz. Thanks for the info.

1st time it seized I was running a 440 main and the second time was a 460. Wondering if the bike is leaning out due to some other cause ?

Bill at BMP Is who I bought my 09 WR250 from and he told me that they remove the reed assembly from cylinder and reseal it because they are bad about drawing air and causing lean problems. Bills did the PDI on my bike and then put it back in the crate and shipped it to me. I can see thin paper gaskets on my reed assembly which I don't think are factory. Maybe you are experiencing this problem. I ran a 460 main during break in and my plug was black.

Buy 2 Honda CR250R's reed gaskets and put one on each side of the reedcage. They fit perfect.

Also, you may want to look at the mag side crank seal and that the pipe is properly fitted at the cylinder. Any of those could be causing a lean condition.