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DR-Z 400 wont idle

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Ok so my neighbor brought over his 2006 DRZ 400S( i believe its an S) after it had been sitting for over a year. At first it wouldnt start so I replaced the air filter, removed the carb, cleaned everything with carb cleaner and compressed air( 3 times) tried adjusting the fuel mixture screw to various positions I read on the forums. Currently its set at 2.5 turns out. I got it to idle for about 5 min with no choke before it died. The fuel cock is leaking and the bike has an aftermarket 4 gallon fuel tank. With that being said it has no fuel vapor seporator but the lines from the canister were still attached to the carb. I detached them because im assuming theyre of no use since the cycle cant be completed now. It also has an FMF exhaust. I also noticed an exhaust leak on the front right side of the bike. Im no expert on dirt bikes and dont own one myself so bear with me if dont use the correct terminology. Im going to do an oil change tomorrow just because I have no idea the last time it was done. The bike has the stock mikuni carb. What do I need to do in order to get this bad boy running right? Im assuming some new jets would do the trick and maybe upgrading the needle? Im assuming putting an extended fuel mixture screw would make life easier too. Im going to replace the fuel cock too. Thats everything I can think of so hopfully there are some subject matter experts out there who can steer me in the right direction.

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Assuming the motorcycle ran before it should not need any mods to run again ,  Just fix what is wrong. Probably needs a new O ring on the float valve seat. 1.5mm by 8mm or 1/16" by 5/i6 ".

 

What jets are in it? 142 main, 22.5 pilot, non adjustable slide needle are stock.  JD Jetting jet kit is the preferred jet kit if i needs one. Jet kit is the only way to get a performance slide needle

 

The original petcock is vacuum operated. The vacuum hose needs to be connected.

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.. something that may be relevant since you obviously had it down far enough to get at the mixture screw, AND you used compressed air to clean it .. 'if' you had the mixture screw out when you blew the carb out (i ran into this and got lucky because i saw it on the floor after) ... theres a microscopic oring in the mixture screw hole that can get blown out into oblivion possibly .. just saying, i got lucky noticing it on the floor .. but chances are if that scenario fits what you did it may be missing in action and maybe could cause idling problems ..

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Noble I have no idea how to tell the jet sizes. It does have a nonadjustable slide needle, so im assuming everything is stock. And I understand that the hoses that run from the petcock to the carb need to be attached but what about the hoses that run from the black canister behind the battery. Since its an aftermarket fuel tank that doesnt have a connection up top for a surge hose (I belive thats what its called, it has a red stripe) then wouldnt the canister be useless? Cowpie, I will check that as well. Ill update you guys tomorrow, thanks!

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Jets are marked with their size. Read the numbers.

 

Yes, the canister is useless.  Remove it and all the plumbing.  Cap the purge nipple on at the carb.

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Ok, I dont feel like a window licker now. I looked for numbers on the jets when I had em off but didnt see anything. Ill check again to be sure but the numbers might be worn off. Thanks

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The numbers do not easily wear off however some aftermarket jets may be produced without stamped numbers and are identified only by the packaging.  If you have unmarked jets, immediately discard.  Replace with Mikuni brand jets of the appropriate size.

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Ok cool, ill get em ordered. Any suggestions for a good petcock brand?

 

I would recommend a raptor petcock, it is a manual (on, off, reserve) type petcock. The stock petcock is vacuum operated and the diaphragm often deteriorates and causes it to leak.

 

http://www.thumpertalk.com/topic/966974-yamaha-raptor-petcock-is-perfect-drz-part-5lp-24500-01/?hl=+raptor%20+petcock

Edited by Wisconsinite762

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I would suggest disassemble the petcock and look at he seals.  The O ring on the plunger can be replaced or sometimes just turned over and the seat cleaned up.

The selector seal can also be replaced. Kawasaki 43049-1066 supposedly fits.

 

My notes also say Yamaha 3AJ-24534-01 and 3AC-24523-00-00 and plunger O ring 4mm id by 2mm thick are the seals needed.

 

I have not personally verified the above P/Ns

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Jets are marked with their size. Read the numbers.

Yes, the canister is useless. Remove it and all the plumbing. Cap the purge nipple on at the carb.

I cant find the cap for the purge nipple. Haha help please

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