JD needles

It has been suggested that the 2008 YZ450F standard needle (#NFLR), #165 Main Jet and a #48 Pilot Jet are a good all around pick for the 2008 WR450F. This combination has been suggested, because you can work around all of the parts of the Yamaha AIS kit. Out of the Yamaha AIS kit all you want is the needle in the kit. You don't need the too rich jets and you can make a metal blank off plate out of thin aluminum, buy vacuum hose plugs at the auto parts store and cut the stock WR throttle stop to the YZ specs from the info on Thumper Talk also. The directions for the free mods are on Thumper Talk, so why spend $50 for a carburetor needle. What have I missed in my reasoning?

Spending more money than you need too. And really how much HP do you really gain. :thumbsup:

I wanted my WR to run like a YZ with a heavier flywheel and an e-start.

So I got an 08 YZ exhaust cam, a Dr. D. pipe, all the freebie mods. I used a Merge Racing leak jet and an adjustable fuel screw. The R&D Flex Jet is the screw to buy.

The new WR's carbs are very difficult to work on so being able to adjust the carb without taking it apart is really nice.

I used an 08 YZ450 stock needle, an NFLR.

The bike took about a 1/2 hour to jet and really runs nice.

I wanted my WR to run like a YZ with a heavier flywheel and an e-start.

So I got an 08 YZ exhaust cam, a Dr. D. pipe, all the freebie mods. I used a Merge Racing leak jet and an adjustable fuel screw. The R&D Flex Jet is the screw to buy.

The new WR's carbs are very difficult to work on so being able to adjust the carb without taking it apart is really nice.

I used an 08 YZ450 stock needle, an NFLR.

The bike took about a 1/2 hour to jet and really runs nice.

Beezer can I have a loan?

How about 3 hunrid dollas?

How about 3 hunrid dollas?

That's a start but I want a wr250 and and a wr250 super moto to commute to work too. soo add about $7000.00 :thumbsup:

Hmmmm you may have to work weekends running the lift at the bunny slope ver the winter......

Hmmmm you may have to work weekends running the lift at the bunny slope ver the winter......

well when Beezer shows up next summer and wants a Montana guide I'll have to charge him the premium rate:p besides I would rather drive the snow cats at night. the wife don't like me to be around the bunnies.

M<MMMMMMMMMM Snow Cat, side of a mountain, a few spliffs, some tunes.... Nice way to spend the evening.

M<MMMMMMMMMM Snow Cat, side of a mountain, a few spliffs, some tunes.... Nice way to spend the evening.

yep!

2316155427_5dff7b4d7c.jpg?v=0

M<MMMMMMMMMM Snow Cat, side of a mountain, a few spliffs, some tunes.... Nice way to spend the evening.

YES! :thumbsup:

The JDJetting kit needles in Yamahas need a much bigger main jet than stock. The larger tip of the kit needle affects fuel flow at full throttle, reducing flow, so there needs to be an increased main jet size or results will be less than ideal. The kit's needles are also tuned at each increment of throttle position with added tapers and specific taper lengths to make a better air/fuel mixture in each throttle range. If there were a stutter from jetting, then the needle clip was probably too rich because there should be less sensitivity to elevation changes with the needle profiles refined to this level.

I also want to mention that WR's commonly have ignition stutter with perfect jetting mixture at low throttle range -and- steady riding. This is NOT jetting, but ignition mapping that goes away when opening the throttle more. The issue is cured with an ignition change, but can be misinterpreted as poor jetting.

See- http://www.pbase.com/jdjetting1/wr450f&page=2

-and below-

99388111.jpg

It could be that Red #3 was needed with a bigger pilot jet. I'm always looking to help if anyone needs improvement with the kit. Please feel free to email me if needed.

Thanks,

James

JDJetting@comcast.net

i ran the JD red needle #3, 48 pilot, 165 main, #50 leak jet, and I personally felt like it didn't run well. It stumbled at quarter to half throttle and seemed anemic at the low end. I'm done. I have tried every combination possible I'm going back to the YZ needle. :excuseme:

I live in Bozeman too and I heard about this cool cat with a WR from here as well having trouble with some jetting. The funny this is the guy was all stoaked to get his machine running tip-top using the JD equipment.

Sadly that wasn't possible. I applaude anyone who tryied as hard as C.D.M. has regarding this issue and kept his cool too!

On a side note, and maybe a bit poking (don't read into it men), what will JD call his kits when the majority of the bikes will be fuel injected.....?

Yo thanks. I know we have talked about it enough. It's done. The YZ needle goes back in. Great ride yesterday. It's fun to have five guys that keep that kind of pace and not get to hung up in the fun parts.:excuseme:

Well, i just installed the blue needle (#3), 170 main and left everything else stock at my '03 WR. The bike runs great and strong. The stutter it had with the Factory Pro kit dissapeared and i am very happy with the result.

Well, i just installed the blue needle (#3), 170 main and left everything else stock at my '03 WR. The bike runs great and strong. The stutter it had with the Factory Pro kit dissapeared and i am very happy with the result.

congrats:ride:

Interested in selling your red needle, charles? After searching the jetting database I made an educated guess as to what my initial jetting should be after all the free mods (just picked up a new to me 07 450) and I cannot find a place to buy only the needle. Or if anyone knows where to find one please let me know.

edit- Or do you think the stock YZ will work for a california desert ridden 450 running a 168 main 48 pj?

Edited by dbshea
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