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DR650SE Needle Comparison

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I was thinking of lateral float. No way you could tune with vertical float.

My misunderstanding...🤣

But, to have that lateral float, even with the extra room in the slide, you wouldn't want the needle held too tightly against it's "seat". On the needle taper...I like the Dynojet taper. Looking at the spreadsheet, it seems to provide just a hair more fuel until 50% throttle opening, so you get the fuel you need to accelerate fast, but for cruising, where the throttle is usually only 50% or less open, you still get decent mileage.

And it certainly delivers if you have it set-up right. I was getting just over 50mpg with my DJ needle. The bike was running very good indeed. My only complaint was the gawd awefull intake noise (air box cover off) I have heard the noise is much less when you do the air box mods and put the cover back on and there are a ton of great different approaches to making those mods posted on this site but I wasn't ready to do any air box mods until I stopped having fun with this jetting thread..... so far I'm still having fun. :applause:

I'm wondering if it might be possible to take a fatter needle and turn it in a drill to make a custom taper? Maybe something halfway between the stocker and the Dynojet, for people with less-than-radical changes to the airbox. Shouldn't be too difficult, with a bit of emory cloth, or a sharp file, or stone..

That's where the KTM needle is in this comparison. I'm thinking it may provide that middle of the road you were speaking of and it's not expensive..... even if a needle jet is required to go with it. The Factroy Pro is right there in the middle ground but it has a few foes in the group because of it's cost and apparent lack of correct jets that come with the more expensive Titanium needle kit. I believe the Mikuni needles are hard coated so machining them would most likely be a bad thing. The Factroy Pro needle is made of Titanium.... nuff said there. I don't know what material the DJ needles are made of... anyone?

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ROB i will get that chart done at lunch time (3am) if you can get me the thickness of the spacer. i dont have my notes here tonight. BTW the DJ needle appears to be of the stainless variety. not sure if it is or not just my guess.

-chris

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My misunderstanding...🤣

I believe the Mikuni needles are hard coated so machining them would most likely be a bad thing. The Factroy Pro needle is made of Titanium.... nuff said there. I don't know what material the DJ needles are made of... anyone?

Darn, Rob, I hadn't considered the needles would be hard-coated. I know from nothing about titanium. Is it too hard to stone down, say with a hard Arkansas stone, or carborundum? Wouldn't have to remove much material. With YZ's speardsheet, you could almost taylor the needle to give the extra fuel you need at any throttle opening. Keep it stock until 60%, say, or even 70%, and then a big increase in opening, and fuel. I wonder if anybody makes aluminum needles? Or brass? I may look into that a bit.

I'm really looking forwards to your results with the A/F gauge.:applause:

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My misunderstanding...🤣

And it certainly delivers if you have it set-up right. I was getting just over 50mpg with my DJ needle. The bike was running very good indeed. My only complaint was the gawd awefull intake noise (air box cover off) I have heard the noise is much less when you do the air box mods and put the cover back on and there are a ton of great different approaches to making those mods posted on this site but I wasn't ready to do any air box mods until I stopped having fun with this jetting thread..... so far I'm still having fun. :applause:

I forgot to mention my total agrrement with. I'm at 4500' elevation, and am running the 150DJ main jet. I'm getting 52-54 mph at my typical 60mph jaunts around here. After reading that the 150DJ is barely bigger than the stock Mikuni140, I'm now thinking of going to the 155DJ. My scoot will not do power wheelies. I'm not sure that's the jetting, though. Could very well be the power loss due to altitude, which is close to 20%, I think. My bike runs very well with the 150DJ main. NO flat spots, surges, etc. I run the clip in the 3rd slot from the top. Stock pipe, and the air box top cut as per Jesse's instructions.

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Hello there to you all,I have set my bike exactly as Idaho Jim has and I am very satisfied with how the bike works.I live at an elevation of about 1000ft and there is a certain improvement from the stock jetting.I must state that since I live in Europe I have installed the European DJ kit that as I realize has a different needle than the US. I believe that the slide spring that Dynojet provides makes a big difference in throttle response since it is much softer.I will try the 160 DJ jet and see how it works.

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Yes, my needle hangs crooked too. It's strange to me that they have it suspended on an edge of plastic like that with no support directly on the other side. :applause:

I wonder if the slide return spring helps the needle hang straight(er)? With that big plastic spacer on the stock needle there may be enough force exerted by the spring to cause the spacer to hang flat on the "ledge" of the step in the slide. I can't imagine why the factory would design the slide that way. Every carb I've ever been inside of has a nice, flat, counterbore inside the slide for the needle clip to rest on. It seems to me that with enough time the stock needle(which appears to be hard coated aluminum) will begin to wear the brass needle jet.

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I wonder if the slide return spring helps the needle hang straight(er)? With that big plastic spacer on the stock needle there may be enough force exerted by the spring to cause the spacer to hang flat on the "ledge" of the step in the slide. I can't imagine why the factory would design the slide that way. Every carb I've ever been inside of has a nice, flat, counterbore inside the slide for the needle clip to rest on. It seems to me that with enough time the stock needle(which appears to be hard coated aluminum) will begin to wear the brass needle jet.

I found a statement on Factory Pro's website last night. It said the "step" in the slide is there to cause the needle to only bear against one side of the needle jet. The purpose is to prevent the needle from oscillating against both sides. Apparently,(according to FP) it's supposed to hang crooked.:applause:

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I found a statement on Factory Pro's website last night. It said the "step" in the slide is there to cause the needle to only bear against one side of the needle jet. The purpose is to prevent the needle from oscillating against both sides. Apparently,(according to FP) it's supposed to hang crooked.:applause:

That makes some kind of sense I guess. When you look at the needle jet with the main removed you can see that the jet needle is up against one side of the needle jet. I never thought about the velocity of the gas as it leaves the bowl and goes thru the needle jet and enters the venturi about the jet needle oscillating. If I decide to go back to the DJ 150 main I will try and take a picture of the jet needle engagement of the needle jet. I tried the DJ 150 with just the snorkle removed and the DJ jet needle installed in the fourth position. It was way rich!! Went for a ride in the mountains with some friends and about wadded the bike the first time I downshifted setting up for a corner and then rolled into the throttle and it almost died from too much fuel. Can you say engine breaking? I rolled into the throttle and was starting to lean into the acceleration when the bike almost died the back started to slide out and the front end gave me a little head shake. About crapped my pants . Just adjusted by riding everything a gear higher and not getting into the throttle as much. After fixing the wifes car yesterday (Bent the right rear strut, "I think I might have hit a pothole" more like a sinkhole LOL) I went back and changed back to the stock main jet and moved the DJ needle to the third slot. Everything seemed better today on the ride into work, but I'll have to wait till tomorrow and give it a proper test. I need to be more methodical like Rob and change one thing at a time, but patience is not my thing. Riding is too much fun.🤣

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ok guys finished the revisions to the excel sheet. heres the one with the shimmed KTM needle.

-chris

percentages-2.jpg

:applause: I like what I'm seeing Chris! That OEM plastic spacered KTM needle in the "0" clip position looks like a lightly shimmed stocker in the throttle range I was concerned with. I'm so slapping that bad boy in this afternoon! A huge thank you for saving me some major in/out/in/out time!🤣

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I wonder if the slide return spring helps the needle hang straight(er)? With that big plastic spacer on the stock needle there may be enough force exerted by the spring to cause the spacer to hang flat on the "ledge" of the step in the slide. I can't imagine why the factory would design the slide that way. Every carb I've ever been inside of has a nice, flat, counterbore inside the slide for the needle clip to rest on. It seems to me that with enough time the stock needle(which appears to be hard coated aluminum) will begin to wear the brass needle jet.

It is bazzare! I plan on paying a little more attention to that again this afternoon when i put the OEM plastic spacer on the KTM needle. I believe you are right as far as the spacer hanging on the ledge because the plastic fits so tight on the needle. The only way for the spring pressure to cock the plastic down on the lower side in the slide would be if there was enough clearance in the fit between the needle and the spacer. No, I'm sure that plastic piece is perched up on the D shaped edge when it's in there. :applause:

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Sorry, gotta ask... did you use the plastic spacer with the Factory pro? If you didn't it would explain the lean out.

Also, the sucky mpg I was getting from that needle is quite likely a result of running a 152 Mikuni and not knowing how darn fat these things are. I'm all the way down to a 147 now with basically the same airbox config and just one extra washer on the stock needle; it runs great.

btw-That Ktm needle looks great shimmed up Chris.

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I found a statement on Factory Pro's website last night. It said the "step" in the slide is there to cause the needle to only bear against one side of the needle jet. The purpose is to prevent the needle from oscillating against both sides. Apparently,(according to FP) it's supposed to hang crooked.:applause:

Great catch Jim!

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Sorry, gotta ask... did you use the plastic spacer with the Factory pro? If you didn't it would explain the lean out.

Wow! Don't tell me FP expects you use the stock plastic spacer?.... Guess that answers that riddle huh? :applause: Me bad for not having the needle Mfg's instructions before playing around with it.

Also, the sucky mpg I was getting from that needle is quite likely a result of running a 152 Mikuni and not knowing how darn fat these things are. I'm all the way down to a 147 now with basically the same airbox config and just one extra washer on the stock needle; it runs great.

Yeah, the 150 Mikuni is just too rich if you are runing anything close to a stock air box. I'm running the 145 right now snorkelectomized, one shim under the stocker and my bike is running great as well. If you are including overall throttle and trips to WFO in the average certainly the main will have some effect. Looking forward to the A/F monitor hook up for the real skinny on that.....

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whew...I was afraid I was gonna insult you with that low ball question. :applause:

No way! Being proved wrong is one of life's great benifits for the soul IHMO. But could the inclusion of this spacer be the reason the FP kit seems to have "the wrong jets" "overly rich pilot" etc?? I'm just asking since I've never laid eyes on the FP instructions, or kit for that matter and there is nothing on their site except "air box mods not required" that is instructive in any way. All I can tell you is my bike produced one of the best torque power bands I have felt on it so far with that needle. Freeway roll on was aweome. I felt if the pilot circuit was richened up I might be able to drop the needle back down a click or two to get rid of that really rich mid throttle portion. I guess when my kit arrives tomorrow (according to UPS) I'll figure this all out. You all will be the first to know that's for sure..... OK, you'll be the second to know.🤣 But this afternoon its KTMuzuki time.🤣

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Wow! Don't tell me FP expects you use the stock plastic spacer?.... Guess that answers that riddle huh?🤣 Me bad for not having the needle Mfg's instructions before playing around with it.

.....

Ya know....if the FP needle is supposed to use the OEM spacer, that's gonna screw-up YZ's Excel spreadsheet.🤣 Hope we can sweet-talk him into doing it again, using the spacer on the FP needle.:applause:

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Ya know....if the FP needle is supposed to use the OEM spacer, that's gonna screw-up YZ's Excel spreadsheet.🤣 Hope we can sweet-talk him into doing it again, using the spacer on the FP needle.:applause:

If the spacer is on top of the clip it shouldnt change the numbers... if im understanding correctly. If not correct me and clear it up. I have no problem making more revisions. this thread has turned into something very interesting. Very good R&D guys

-Chris

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Snipeage...... this thread has turned into something very interesting. Very good R&D guys

-Chris

You think so far is interesting? Check this out..... I slapped the plastic spacered KTM needle in with the clip in the top position and the bike did almost the same thing it did when I first tried the spacerless FP needle with the needle in the middle position! I could tell how it ran that it wasn't quite as lean so I took it back apart and went directly to the middle position.

Oh so close baby! :applause: There is just a fuzz of lean right off that "just past idle part of the throttle" Power is smooth and wide. Slightly softer in the first 1/4 throttle or so but builds very quickly above 1/2 to 3/4 throttle. I ended up at my self inflicted limit of 3 on cranking out the pilot screw. A 45 pilot jet is what this things needs for sure. I've got pilot jets coming from Jesse. For a stock air box with only the snorkel removed this thing goes like crazy. With a good quick roll-on from about 1/4 throttle in first gear my DR lifted the front wheel off the ground in a nice power wheelie until it ran out of steam on top. That's with my lard-*ss 215lb in my birthday suit fully geared up, front moose tool kit and a way heavier Kings KT-966 front tire. This is with stock 15-42 gearing as well. No, I didn't have to klammer for the rear brake... it just lifted the tire a few inches and held it till rpm ran out. The bike ran smooth as glass with very linear throttle control on the freeway. From trailing throttle coming back into very light acceleration again is where you notice the lean spot. It really improved going from my 1-5/8 pilot position to 3 turns out. I could probably crank it out some more but this is telling me there is a problem in that circuit so I'll just fix it correctly. I filled the tank right as I crossed the border and I'll check it on the way in tomorrow morning but I'm pretty sure I need to run it a couple days to get a more acutrate representation compared to my normal routine. I was tweaking the throttle pretty hard checking how it was running at various loads. Can't wait to ride it back to work in the morning! Hold tight guys, we may be on to something here unless the fuel mileage slaps me into reality. Only time and a couple more adjustemnts will tell. DAMN I need the A/F monitor hooked up!🤣

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Wow been gone for a while. You guys wrote a novel since I've been away. Got a lot of reading to catch up on. And 10,000 other things to do as well.

This is an awesome post!! I guess you all are getting down to the nitty gritty now. Pretty interesting stuff about the KTM setup. The dynojet needle is so different.

Hey Rob what do you need for the A/F monitor hooked up? I figure you already stated in an earlier post that I didn't read yet, sorry. I have herd about it before but can't remember much. Maybe we can take up a donation? Or perhaps someone has what you need laying around.

You guys are great for taking all this time to do this. :applause:

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