All these YZ mods to a WR???

No speedo or blinkers(no night riding though) necessary in WA state to make it street legal, but good luck getting it tech inspected by WSP nowadays. Might as well ask for the second'll happen sooner

than getting your bike teched in this state!

You Eastern WA guys have a better shot at it than anyone here on the West side.unless you're a State Patrol officer rolleyes.gif


Y2K WR400FM,Answer top tree w/Accu-Trax clamp,Pro-Tapers(CR-Hi w/ EE handguards),Devol Rad. & frame guards, Guts tall soft foam w/ ballistic cover, 14/52 w/DID VM X-Ring, Kouba-T,Michelin M-12's ft.& rr.,12 oz. flywheel weight, Zip-Ty Racing Link & Shark Fin(plus everything else cool that Ty offers), Cycra front rotor guard and T.M. Designworks Chain guide, buffer & chain wheels. Street legal except for the non-"DOT" tires.

I see you are also from WA state. I am too. What did you have to do to get it (semi) stret legal for dual sport status? Is there a break light kit available? What else is needed for legally blasting down fire roads?

Originally posted by Bill:


de-oct is removal of some air hoses (on the carb) that are specific to 98-99 US version WR's. You can view the octopuss in the tech section.


Where in the tec section. What is it called. I could not find it


I also looked for the article but could not find it. Clark Mason removed his due to inadvertantly snagging one of the hoses and yanked it out of it's tee fitting. To prevent a lean condition from occuring (also ingesting junk into the carb), Clark removed his octopus (also called the air cut valve)and went w/ YZF air jets. I did the same. After reading about Woody's 426 and the air cut valve preventing a lean condition on decel, I wonder how much of an effect this bogus octopus has on the pilot fuel system(?)

It is common knowledge to offset backfiring on decel by going out on the fuel screw. With the octpus removed, the bike may be exibiting a lean condition on decel but may be jetted fine on acceleration...(???)

If you want, I can give a step by step instruction on how to remove it. If nothing else, it GREATLY increases the asthetics of the carb and reduces the chance of snagging one of the vacuum lines. smile.gif


'99 WZ/YR (you choose!) with ALL YZ mods, de-octopused, DSP Doug Henry airbox w/ velocity stack, FMF PowerBomb header, Stroker SX-1 silencer, SS front brake line, OEM YZ tank, IMS YZ seat, Mobil 1 15W-50.


go to

click on > WR400 > Technical > scroll down a bit and look on the left under "Jetting" at #3 "more on jetting and how to remove the octopuss"

I went to Autozone or Advanced for the vacum caps. They even had Yamaha blue grin.gif


Thanks Bill. So do you have to be YZ timed to do this DE-Octapus thing or not. Thanks again.



If life is not a blur. You aren't going fast enough


I did the de-oct several months before I did the YZ timing. I used the jets and directions Clark outlined and had no problems.


Khris, I just had my 400 yz rebuilt and had lower 1st, and taller 5th installed. I think this will be the best of both worlds, reason being close ratio 2,3,4th gears and hyperdrive 5th. Also 8 ounces of flywheel weight to get the power to the ground. Cost of the gearsets was 170 bones.I am excited about having the new lower 1st more than anything. There are times when slipping the clutch gets old fast. Keeping up on the mainroads will be good too.

later, huge

Here you go, from the tech section on Octopus removal:

There are a few jetting differences between the YZ and the WR. The YZ uses a 175 main jet stock and the WR a 168, the YZ uses a DVR needle and the WR a DTM both use a 45 piolt jet. The WR uses a more complicated slow speed start circuit with a lot of complicated vacuum hoses, and two start air jets. The WR secondary start jet cuts out as soon as the engine starts and generates manifold vacuum. Thats what the vacuum module on the side of the WR carb does, remember I live in the USA.

The DVR YZ needle is way leaner than the WR needle at and just off idle, this is why so many compaints are made about the bike poping on decelearation with the YZ needle, because it goes from WOT to lean in a heartbeat. NEVER RUN THE (YZ) DVR NEEDLE IN A WR WITHOUT THE YZ CAM TIMING YOU WILL OVERHEAT THE ENGINE AND RUN WAY HOT.

Heres how the needles stack up from richer to leaner DTM, DTP, DVN, DVP, DVR.

What I have found to work best is to use the YZ cam timing, a DVP needle (YAMAHA PART # 5BE-14916-DP) (#3 or #4 clip from the top), 48 pilot jet, idle screw 2 to 2.25 turns out, 178 to 185 main depending on altitude. The 180 is a good all around choice. ___________ ___________

If you have a WR and want to eliminate the vacuum module and extra hoses which I tend to knock off and cause a vacuum leak read on.

Parts required: 1) a YZ pilot air jet #100, 2) a YZ start jet #65. Avaiable from Yamaha look at the YZ parts listing, 3) A couple of small automotive vacuum line rubber/plastic blocking caps.

Remove the carburetor

Remove the vacuum module from the left side of the carburetor and all associated vacuum hoses.

Plug the exposed vent port on the INTAKE AIR HORN side of the carb with a standard rubber/plastic automotive vacuum plug cap. Plug the exposed secondary start air jet input--on the left side of the carb with a second vacuum plug cap.

Remove the carburetor float bowl and change the start jet in the carb from a #60 to the YZ #65; reinstall the float bowl.

Change the #1 Pilot air jet from a #75 to the YZ #100--note this air jet is behind the air horn on the bottom. Remove the air horn via two screws look at the carb there will be two air jets on the bottom its the one on the left, reference your manual this is easy. Carefully reinstall the air horn using the two screws.

Be sure to make any other jeting changes you may have in mind at this time.

Reinstall the Carb in the Bike.

Now connect the hot start button vacuum line (the longest vacuum line)directly to the vacuum port on the HEAD INTAKE MANIFOLD.


This eliminates a lot of stuff from the left side of the carb, eliminates multiple vacuum connections (sources of vacuum leaks), saves a little weight and works just fine. My bike is an easy staring machine.

Hope this is of benefit



'99 WZ/YR (you choose!) with ALL YZ mods, de-octopused, DSP Doug Henry airbox w/ velocity stack, FMF PowerBomb header, Stroker SX-1 silencer, SS front brake line, OEM YZ tank, IMS YZ seat, Mobil 1 15W-50. 6 speed in your YZF? Or did you do a WR gearset in your YZF? confused.gif


Buy one of those MSR ISDE Gore Tex jackets? Got one, black /purple, $126 with shipping. Not a better buy anywhere.

WR400rock .....web adress for your 126 $ Jacket ???

ciao bello


The Missile

'99 WR400F

Airbox Lid - gone

Throttle Stop - shorty!

Plastics/Tank/Seat - One Industries

Street Legal

Blue Thunder, I had a WR 1st and 5th gear installed along with a new 2nd gear set. I am not sure if the wr 2,3,and 4th gears are of the same ratio. I do like the close ratio box better than the wide, but seem to run out of gear when hauling freight alongside my friends Husky 610. picture this me tapped out in fifth we are talking 12,500rpm @80mph side by side with the Husky down this fire road as he looks over at me and grabs another gear. Damn I hate that.I still out braked him into the next corner but down the next strait there he was. Its a top end thing the 400 keeps up every where else. I can't wait to see the look on his face as I rev out fourth and pick up fifth alot lower in the rpm range. With the lower first I should be able to pull taller gearing which hopefully will put me around 100mph flat out . Thats my goal anyway I know the Husky is good for around 110 WFO so for him to come by me now he had better have brass balls!!!

optomistic, huge


Donelson Cycle is the retailer of the MSR ISDE Gore Tex jackets. Good luck. Actual cost was $126.95.

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