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Top end lean condition after 3X3 mod.

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I didn't have time to search the forum since I'm taking my lady out for a Feb 14 lunch so I figured I'd just short-cut the system and ask.

If this has been handled in the FAQ...please just say so and I'll search it out later.

Anyway...here's the thing.

Did the 3X3 mod, 25 pilot, dynojet needle with clip in position 4, 140 main, modified end cap.

Running fine and pulling strong up to about 75 mph in top gear....oh it's a 2004 S model.

At about 75 I get a slight surging that I'm thinking is a lean condition on top.

I changed to a 142.5 main and just test rode it...it seems to be marginally better but the surging is still there.

Am I on the right track in making the main larger or should I consider raising the needle one more notch or using the "1/2 notch" shim.

Since it's 50 degrees with 70 percent humidity here (at sea level by the way) instead of the normal 80 to 100 deg with 15 percent humidity maybe this won't be a problem at all during the summer..

Waddayall think??

Ray(just a touch more fuel please)Stedronsky

Davis, CA

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Hey Burned,

Yep...stock gearing.

There's still more throttle at 75...probably open just a bit more than 3/4 but not quite to 7/8 open. God that sounds like an answer my wife would give....but it's the best estimate I can give ya.

Tuning bikes by remote control must be a real joyhttp://www.thumpertalk.com/forum/newreply.php?do=newreply&p=1744423&noquote=1#

Thanks for any help you can provide....it's dark and rainy now so a test ride is probably not the best thing at this point.

Ray(willing to get wet if he has to)Stedronsky

Davis, CA

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Try this. Put tape around your handlebar next to the throttle and mark the closed, and full open throttle posititons. Next mark the 1/2, then 1/4 and 3/4 position. Take a ride and you can tell where the problem is at the throttle position easier.

I had the same problem and it drove me nuts for a long time. I finally opend up the top again and found the little spring (not the large slide spring) had some how poped loose inside. I put it back together right this time and no more problems.

Also did you put the washers in the right place on the needle. The thick washer on bottom I believe.

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OK....

Carb will come off tomorrow and the tiny washer will go under the needle.

I'm assuming that the last part of the needle is still inside the needle jet even at full throttle so the needle is still having some affect on mixture...oh wait that makes sense since if the needle came out completly is just might not go back in...get stuck...and then it's "lets see if you can stay on for the next 6 seconds" time.

Is the best way to post results and any other questions just to add to this thread? I'm assuming you get way to many pm's already.

I'll do the work tomorrow during lunch but won't be able to really ride until Wednesday morning so I'll post results then.

Thanks for the assist

Ray(feeling special after communing with the jetting God)Stedronsky

Davis, Ca

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Hey...Burned's right you don't have to take out the whole carb to get to the needle...

So I had some dinner, some wine and went out to the garage to solve my problem...Tank off carb top off....needle out....OK...lessee....find the small washer and put it under the circlip thats nice and cozy in the third slot and......THE THIRD SLOT!!!!

crap

The one time (right) that I don't double check my assembly and I screw the pooch...yeah...that's right the clip was in the #3 slot and NOT and #4 slot.

Moved the clip to #4...made sure it was #4 and put the 140 main back in. Buttoned it all up (does it seem wierd to anyone that the slide is held together by just a small O ring....or is it just me??) double and triple checked everything. It's now 10:00 pm and the neighbors have a new baby...so...ride the bike to work tomorrow and see how it works.

I'll post again after I find out.

Ray(yeah I'm an idiot)Stedronsky

Davis, CA

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It's now 10:00 pm and the neighbors have a new baby...so...ride the bike to work tomorrow and see how it works.

I'll post again after I find out.

Ray(yeah I'm an idiot)Stedronsky

Davis, CA

Still raining in norcal, be careful out there. I had the same problem after

my 3x3 dynojet mod. Only happenned @ 75mph+ @ 3/4 or so throttle.

Moved it to "clip 4.5" per burned's instructions, no more surge. :) :)

Here is his answer from a while back:

"put on dj washer under the clip, makes the clip position 4.5. "

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Yep all the washers are in the correct order.

I don't think I'll need position #4.5 since I didn't have #4 in the first place. Going to work in a few min and we'll see then.

No active rain now but I found a long time ago that the only way to be good in the rain is if you actually....wait for it....ride in the rain. After a few rides you adapt to the manhole covers, crosswalk stripes, turn arrow stripes, wet leaves, and all the other junk just like you do on the dirt.

Having the DRZ instead of a 600 lb. street bike also makes this much easier.

Results soon

Ray(wet feet)Stedronsky

Davis, CA

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Rode the bike to work:

Lean surge still there more prounouned now. Noticable in the lower gears (140 main and clip in #4) than in was yesterday (142.5 main and clip in #3).

I know I need to just change one thing at a time so I added the small dynojet washer under the clip during my lunch hour.

Jetting now is 140 main clip in position 4.5.

I won't be able to ride home until tomorrow morning so I'll see how it feels then...question is...if it's still surging a bit do I go to the 142.5 main or raise the clip to position #5.

Ray(waiting for the morning)Stedronsky

Davis, CA

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Wow...I don't mean to be confusing so let me recap.

First, yes, I'm counting from the top (flat) end of the needle. The first groove (closest to the flat end is #1)

When I first did the mod I mad a mistake and had the clip in #3 when I though I had it in #4. With this set up the bike had a lean surge at about 7/8 throttle and high rpm noticable in 2nd 3rd and 4th....felt rather like the rev limiter but was at too low of an rpm for that to be right. In top at about 75 the bike had a lean surge with about a 1 sec cycle.

Before I wrote you the first post I thought I'd change the main to the stock 142.5 to see if that would cure the surge. It seemed to help in the lower gears but was still present at 75 or so in top gear.

After your posts it was obvious that I didn't have to remove the whole carb to get the slide out so and we were talking about putting the dynojet shim under the clip....so...yesterday evening I removed the top and found that I'd mistakenly put the clip in #3 and not #4.

I moved the clip to #4 counting from the top (flat) end of the needle and put the 140 main back in. I didn't use the dynojet shim.

Riding to work this am (50 deg 90 percent humidity, light rain, sea level) the surge was still present on top and more noticable again in the lower gears. It seemed a bit better in #3 with the 142.5 than in #4 with the 140. Is this what doesn't make sense???

So today at lunch I put the dynojet shim under the clip...clip still in #4 and kept the 140 main in the carb. I won't be able to ride until tomorrow morning on my way home to see how it works....I'll have the whole day tomorrow to work on it though.

All the help is greatly appreciated. If I should be getting more fuel with the 140main/#4 clip than with the 142.5main/#3 clip then something is indeed strange.

Mucho thanks for the ongoing assist.

Ray(determined to get this right)Stedronsky

Davis, CA

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That's what I thought you might say...what I feel doesn't agree.

The difference it not that pronounced....it's only surging not bucking, detonating or doing anything else bad. It actually runs very well up to 3/4 - 7/8 throttle. It just seemed a bit better witht he 142.5 #3 than the 140 #4.

Just to make certain I have the washers in the right order on assembly the parts are as follows from top of the needle to bottom.

1. Plastic cap with O ring

2. small spring

3. Thin silver metal washer

4. Circlip (now in groove #4)

5. Dynojet shim (small washer) to give me #4.5

6. White plastic/nylon spacer (about 3-4mm thick)

7. Brass washer (about 2mm)

8. Carb slide

I'll ride the bike home tomorrow am and see how it does.

thanks for sticking with me on this.

Ray

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That's what I thought you might say...what I feel doesn't agree.

The difference it not that pronounced....it's only surging not bucking, detonating or doing anything else bad. It actually runs very well up to 3/4 - 7/8 throttle. It just seemed a bit better witht he 142.5 #3 than the 140 #4.

Just to make certain I have the washers in the right order on assembly the parts are as follows from top of the needle to bottom.

1. Plastic cap with O ring

2. small spring

3. Thin silver metal washer

4. Circlip (now in groove #4)

5. Dynojet shim (small washer) to give me #4.5

6. White plastic/nylon spacer (about 3-4mm thick)

7. Brass washer (about 2mm)

8. Carb slide

I'll ride the bike home tomorrow am and see how it does.

thanks for sticking with me on this.

Ray

Here is the exploded view

http://www.ronayers.com/fiche/300_0313/carburetor/carburetor.cfm?man=su&groupid=1650&parent=1610

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Check for air leaks and vacuum leaks. The CV carb diaphram may be sensitive to leaks and move the needle slighly.

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