LRD 330R Jetting issue.. HELP.

[atcmatt]

Went to the beach today, with Mart, to try and get my R jetted right. Got close but need some advice.

It's running an LRD 330, boyesen reeds, FMF gold series Fatty, 38mm PWK Airstriker, no airbox lid.

First up, it wont idle unless the idle screw is right in. It idles good though. It has a 40 pilot jet. We went up to a 55 jet and it still did the same thing. But idled crap, like burbling. Adjusting fuel air screw hardly changes idle speed. Now maybe it needs a bigger pilot jet? Like a 65?

From idle to mid-range you can whack the throttle and it cracks. Seems to run fine off idle and through mid-range. Clip is on the middle notch.

This is where it gets me confused... We went from a 190 main right down to a 160 with all sizes in between. The bike would just splutter at WOT, no matter the jet size. It seems to do it less on the 170, but is still no good.

Do you think I need to go leaner than this? Or will it be too lean anywhere under 160?

Maybe this is an electrical problem? Stator not big enough? (Just a stocker)...

Where do I start?

Thanks - Matt.

[Billy Golightly]

Pilot jets go like 40, 42, 45, 48,50. So going from a 40 to a 55 was a huge jump. 40 is definitely way lean. You'll need probably a 50, 52, or 55 pilot. Its normal for the idle adjuster screws to be turned in all the way. Sometimes you actually have to take them out and cut the spring down for it to go in far enough. On the topend I think your on the right track thinking electrical, but don't toss any of the OEM stuff. Take your spark plug out and gap it down to about .015-.018in (A little less than a 1/2 of a milimeter). Is it smoking when its bogging at top end? If its not, the spark plug gap is too wide and the engine is blowing the fire out at higher RPMs. Too many people chase their tales with jetting on this issue.

[atcmatt]

Thanks Billy. Im going to try a bigger pilot jet and see if it still idles alright. Mart said that a 40 was real lean. Doesnt seem to be smokey at all on top end. Ill get a few new plugs today and gap them properly and see how it goes.

Matt

[atcmatt]

Im leaning towards something electrical now for sure. I put back in a 52 pilot, runs horrible and really smoky. I settled for a 48 pilot. Seems to be a happy medium. Its not getting a decent spark, its not a big fat blue one at all, i put the coil on my es and the coil seems to be fine as the es gets a real fat blue spark. Whats the next step then, a new stator? Flywheel?

[ChrisD]

I am sorry for the long response.....short answer....get your jetting close, then play with your needle.

This is a tough one to nail down, but I can tell you my experience. I have an ESR 330. I run a modified KX500 Rad Valve, a PT Hi Rev, a 40.5mm Keihin, no airbox lid. I upgraded it from a ported 250 motor with a 39mm Keihin, standard 250 Rad Valve and the same PT Hi Rev. All else was the same. I do, and did at the time, run a PVL ignition.

Anyway here it is. I ice race the bike so it's a cold weather motor, meaning it runs leaner due to the lower temps. So, under the same conditions, I went from running a 200 main jet to a 175 when I went from the 250 to the 330. I also went from a 60 pilot to a 58. Completely the oposite from what you thought it would be. You would think, bigger motor, then it needs more fuel, definitely because you were running a bigger carb.....wrong! I went from a 39mm to a 40.5 and 250cc to 330. It went the opposite way. Jetting....I was worried when I went to a 182 from a 185, then really worried when I went to a 180....this can't be right?!?!?! Well I settled at a 175 on warm days (35-45 degrees) and a 182 on really cold (15-25 degree days).

For those at Bryan Raffa's ice fest last year, they saw my frustration! I could not get it to run right on top end AT ALL for 3 or so hours. I changed main jets back and forth, pissed at the world. I finally gave up, thinking it was the ignition. Then I remembered one thing I did change befor my trip up there (I had previously put a new piston and bore in the motor) I moved the needle clip down one notch (making it richer). I then chenged the clip position on the needle and the bike CAME ALIVE! Crystal clear and strong. Not a hesitation at all, no break up on top. After all it was not my main jet, but my clip position that screwed the motor performance.

Keep in mind that my motor will differ from yours in that the temps are 50-60 degrees colder so you will need smaller jets.

I would keep doing plug chops and make sure you are not lean (not a dry and white plug) and go down in jet size until it is close to running clean, then play with the needle.

Advice:

1 I would call LRD and ask them for their standard set up on the jetting and which needle to use.

2 I would keep asking questions of guys who ride in the dunes......all of the message boards to compare set up.

3 Stator.....it happens and it has happend to me 2 times. You can usually tell the difference between jetting issues and electrical. Electrical is more power on...power off...litteraly. Jetting is more....I can't get it to clear out, but it acts like it wants to. If you have an idle issue, then try a timing light on the plug wire and a car battery to make sure the spark is consistent. You can always test the stator and I can provide the specs if you want. Stators seem to "go" right after you have messed with them like a rebuild or something like that.

Anyway, you can PM me and I can try to help further if you have questions.

[atcmatt]

Thanks Chris. Had a bit more of a tinker with it tried hotter and colder plugs. The best result Ive had so far is the 170 main, 48 pilot, and the needle on the 2nd clip down from the top. Have not yet done a plug chop so no idea if its lean or rich. Still isnt the best on top end. Bogs down but is alot better than it was. I dont know where to go now, maybe I just get a new stator and see if that changes anything. This is why I never liked two strokes haha. They are good once they run well though. Not sure if she is going to be too lean with the needle second notch from the top. Any thoughts?

Matt

[ChrisD]

Is it only bogging at WOT? You said that you tried different plugs. How were they when you took them out? Were thru dry or wet? Any brown on them? I'm on my way home now so I don't have it wig me but I think 1/2 to 3/4 throttle is clip position and obviously the last 1/4 is your main jet. Do you know the sound of a 2 stroke death rattle (sound of detonation) ? If so, have you had any odd pinging from the motor at top end? If not you may still be able to go down another jet size. You have to remember that a big bore motor will pull a lot of fuel from a small jet. I' hate to cook hour motor, but if it's breaking up on top you probably won't blow it up anyway if you do a short burst of top end. I couldn't believe how small of a jet I went to. A175 on a 40.5 carb is small. It's even smaller than an identical ESR 330 that JohnR runs under the same conditions.

[atcmatt]

Yeah only at WOT it just bangs. More like ting bang ting bang ting bang and very uneven, not so much bogging. Like it wants to get on the pipe but just cant. The plugs were both wet in each ocassion and i didnt run it long enough for them to get brown at all. Im starting to think it is the stator, its just getting a weak spark and I think that it may be enough to burn the fuel on low rpm to mid rpm but when it gets up top and gets really fueled up it can only burn so much because of the lousy spark. The lowest jet I went in it was the 160 and it was still doing the same thing. Just falling over itself at WOT. Im not sure what the death rattle sounds like, I just dont wanna keep going down in jet sizes coz im scared I will lean it out way to much and have an explosion! Im just completely lost now. Say i put a small jet in something around 140 - 150, this will be putting my motor at risk wont it, evn if im just revving it up stationary?

Thanks Chris.