WR400F

Discussion in 'Thumpers' started by a1fa, Jun 5, 2009.

  1. dvgonzo

    dvgonzo Been here awhile

    Joined:
    Dec 26, 2004
    Oddometer:
    343
    Location:
    Albuquerque, New Mexico
    Well I decided to off load the 400. Hate to but have just decided the constant kick starting when clearing trail is just not the hot ticket due to the new parts I had installed on me! (New aftermarket knee!)

    Fortunatley I have a later model one ('03) that came with a button!

    I ran an ad here locally and got no response...yet...probably cause it is mid winter and I priced it pretty high due to all the extra's I have for it.

    I am now thinking I should start to off load some of the extra's and discount the price accordingly as they sell.

    Here is the link to the ad, really pimped out and so much extra stuff for it! No pics as camera is dead. If interested in any of the parts let me know.

    http://albuquerque.craigslist.org/mcy/2785551865.html
  2. RandoCommando

    RandoCommando Wannabe

    Joined:
    Oct 12, 2011
    Oddometer:
    1,729
    Location:
    Philthadelphia, Pennsylvania
    Ok. So I found a bike near me that is for sale as stated in the title.
    A few questions.
    Has anyone had any problems converting this to a street legal dual purpose?
    What kit did you use?
    Is the seat height 39"?
    Can it be lowered for cheap? If so,with what lowering links?
    I found lowering links that were like $150. YIKES!
    I've also read conflicting specs on this.
    What is the actual wet weight and horsepower?
    Lastly. Is $1500 a good price for a one owner bike that was well maintained?
    I have a KLR 650 that I currently ride the streets and trails, but it's a top heavy beast with low power.
    I'm thinking the WR400 might be a good alternative for the dirt and trails.
    Any and all help/advice is appreciated as I'm looking to buy this week.
    Thanks!
  3. marbee40

    marbee40 Some Fear is Good

    Joined:
    Jan 28, 2007
    Oddometer:
    1,738
    Location:
    Awfully close to the Marsing Cemetary
    2001 WR426, no mods.

    Bought this year. Ran like a champ after cleaning carb. I'm the 2nd owner.

    Two weeks ago, bike stalled, no compression. Pulled apart. Found two pieces of the little cam shim laying down below the rotor (flywheel?). Didn't know what the metal was, but it definitely broke the cam chain. Popped the covers off the cam and found one shim correctly in place above each cam. Original owner (or mech) must have dropped one at some point and neglected to go after it. :-(

    Pulled head and cylinder. Piston and valves look to be in excellent condition. Did NOT pull valves, just looked at all five plus piston. Didn't appear to be any damage.

    Put on new cam chain, set piston TDC, put cams on correctly per the manual. Put it all back together. When kicking I get no compression...ie when kicking, the kicker doesn't come to a stop, requiring the use of the compression lever on the bar. Used to start 1st time, every time.

    Ideas? Is it possible the previous owner had the YZ timing (rotated exhaust cam one tooth clockwise) and now it won't start cuz I have is set to WR stock? Maybe a bent valve that I can't see unless I pull them out?

    THanks,
    Jim in AK
  4. dvgonzo

    dvgonzo Been here awhile

    Joined:
    Dec 26, 2004
    Oddometer:
    343
    Location:
    Albuquerque, New Mexico
    Bummer!

    Are you sure it was one of the cam chain adjustment shims? Did you find it all? Or enough to tell for certain that is what it was?

    Reason I ask is just to be sure it is not a flywheel woodruff key as that could also break the chain and would look sort of the same after getting chewed up by the chain/sprocket. Would also keep timing chain from turning and piston/valves from cycling up and down. I imagine you would have noticed that though....just a thought.

    A few weeks back two buddies were doing a KTM and dropped a shim, they looked for several hours, used magnets, wire , mirrors, and finally gave up. I got lucky and found it within a couple minutes of starting to look for it and can see where some folks would get tired, button it up and later it breaks.

    Could you tell if it got caught up high in the cam area (marks on the cam sprockets, caps, etc?) or down behind the flywheel or in the chain tensioner area? It should have left a few marks and maybe some other damage if when it got caught and stopped the motor.

    Sometimes the sudden stop will shear off that same flywheel woodruff key I mentioned earlier, or weaken it enough it will finish breaking if re-used.

    Keep us posted.
  5. marbee40

    marbee40 Some Fear is Good

    Joined:
    Jan 28, 2007
    Oddometer:
    1,738
    Location:
    Awfully close to the Marsing Cemetary
    I just tried to upload the pic of the cam shim and the broken piece but tapatalk giving fits. Anyways, thats what it was. We had pulled the flywheel to install new chain and woodruff on crank is fine.
  6. dvgonzo

    dvgonzo Been here awhile

    Joined:
    Dec 26, 2004
    Oddometer:
    343
    Location:
    Albuquerque, New Mexico
    I would then try to see where the shim got caught like I mentioned, up high or down low and see if it might have mushed out some other metal or a sprocket tooth that might be stopping or catching the chain.

    Depending on what it stopped first (cam, chain,) and where it stopped it up, (Shim against a bucket, or cam cap, etc.), will determine what else got trashed out.
  7. marbee40

    marbee40 Some Fear is Good

    Joined:
    Jan 28, 2007
    Oddometer:
    1,738
    Location:
    Awfully close to the Marsing Cemetary
    Oooh.... Good points. My "ass-ump-shun" was it hopped up off the bottom of the case and wedged in btween the crank gear and cam chain. Ill look for tweaked teeth, etc.
  8. marbee40

    marbee40 Some Fear is Good

    Joined:
    Jan 28, 2007
    Oddometer:
    1,738
    Location:
    Awfully close to the Marsing Cemetary
    Both outside intake valves tweaked. Ordering tinight.
  9. dvgonzo

    dvgonzo Been here awhile

    Joined:
    Dec 26, 2004
    Oddometer:
    343
    Location:
    Albuquerque, New Mexico
    I would imagine since it is two they may have contacted the piston.

    I see where you said the piston looked good but can you see any faint marks or gouges on the piston or valves to verify that is what caused it?

    Valves can get bent pretty easily when a piston contacts them so
    hopefully was not to hard a hit so nothing else got wankered.
  10. marbee40

    marbee40 Some Fear is Good

    Joined:
    Jan 28, 2007
    Oddometer:
    1,738
    Location:
    Awfully close to the Marsing Cemetary
    I finally got the durn thing running with the help of AKMud and Friar. Long story short, one silly little dropped cam-clip required a new cam chain, two new titanium (UNOBTANIUM) valves, two shims, and a woodruff key on the crank to get her going again!

    Thanks all!

    Jim
  11. Kawidad

    Kawidad Long timer

    Joined:
    Jul 9, 2005
    Oddometer:
    6,620
    Location:
    Central Coast, Cal
    Too late now, but Ti valves are not a good idea. Check them often. :deal
  12. MingRidesBikes

    MingRidesBikes Been here awhile

    Joined:
    Oct 17, 2010
    Oddometer:
    322
    Location:
    Honolulu, HI
    Hey guys had some questions for ya about the wr426f. I recently purchased an 01 wr426f. looking to get the most power out of this bike. I had a 05 wr450f deristricted that was an absolute blast to ride. With that said I like my new to me 426 a lot. Smooth shifting, linear power band, but would like some more umph. it currently has a yz426 pipe on it. what mods will really bring it alive? I was thinking over the winter to do a yz450 exhaust cam, was contemplating getting a yz426 aftermarket pipe (i.e. fmf or a t-4) not sure how much more power that would be than the current yz pipe on the bike. Anything else to help bring this bike to life? And honestly will it ever have the power the 450 had? Thanks for your input guys.
  13. Kawidad

    Kawidad Long timer

    Joined:
    Jul 9, 2005
    Oddometer:
    6,620
    Location:
    Central Coast, Cal
    Not really a power expert, but the cams will help. However, the supposed gain is in ease of starting, not really a power mod. Another mod you can do is switch the carb to a 450 carb. Again, it is supposed, the internals of the carb are better engineered since it's newer so that allows the bike to run better. I did it on my WR400 and it worked pretty well, but more power, who knows.

    Honestly, though, only by dumping big $$ into it will you get any reasonable performance gains out it. Otherwise, it's only going to be modest gains, if at all. :deal
  14. LucasLeader

    LucasLeader Been here awhile

    Joined:
    Mar 21, 2010
    Oddometer:
    299
    Location:
    Anchorage, AK
    Make sure this is done first: http://www.thumperfaq.com/throttle.htm The WRs can only open to 3/4 throttle from the factory. That site is for 250s but still applies to your bike. Check out the other free mods on there and do all of those. Also get your jetting squared away and if you have a bad bog look into messing with your accelerator pump. I've heard people say the 426s can be just as fast with the 450s with the basic mods.
  15. yamahaman

    yamahaman wannabe bike builder

    Joined:
    Jul 28, 2010
    Oddometer:
    224
    Location:
    melbourne Australia
    I have got a Hybrid yz/wr motor and I have tried everything with some good sucess and some bad! From personal experience the 450 cam is Not Quite right. If you can afford it, the hotcams (no affiliation) cams specifically for the 426 in the yz is really good http://www.hotcamsinc.com/ProductInfo.aspx?item_id=566
    more power, easy starting and no stalling when brake sliding due to the auto decomp

    The bk mod
    http://motoman393.thumpertalk.com/tech/carbpics.html
    http://motoman393.thumpertalk.com/tech/carbinfo.html

    Make sure you have this matching carb with the red hot start button

    The last option is the Vortex ignition I am friends with the owner of vortex and he has given me one of these that is tuned for the wr lighting coil/stator and it has a max power tune and a max tourque setting awesome http://www.vortexcdi.com/model_product.php?product=1&model=33&mp_id=1336

    These three mods will give you all you need to give the bike all you can without loosing reliability


    I have had Standard yz pipe, Titanium DSP pipe, FMF and also currently running a CRD pipe the power is un-noticable between all of the aftermarket pipes, just keep the yz its neat, works ok and not overly loud.

    I also have mixed the yz and wr grearboxes to make a custom box 1st wr 2nd yz 3rd yz 4th yz & 5th wr (this was popular with the european enduro guys when the bike came out)

    I have run the wr box and yz box, I have found the yz to last the longest and be the most useable in the woods where as the wr box is a bit better for the open stuff. Be aware these bikes are suseptable to fifth gear not holding due to loading up the gear and not reving it out dont labour the bike in fifth keep it on the boil and the gearbox will last

    I have done heaps of work on these motors and have come accross all of the major problems that can be encountered with them, great bikes if you know there limitations and more help pm me

    :1drink:1drink:1drink
  16. MingRidesBikes

    MingRidesBikes Been here awhile

    Joined:
    Oct 17, 2010
    Oddometer:
    322
    Location:
    Honolulu, HI
    Thanks for all the info! I'm gonna be reading into the carb and ignition mods. Didn't think these would be substantial area's of opportunity. I do need to check the throttle stop screw for sure. I know it has the yz pipe I believe off an 2001? they are different between 01 and 02 if I'm not mistaken. And when doing the hotcams from the 426f, The exhaust is for auto decomp, the intake is where the power comes from correct? Jetting I'll have my shop dial down, is there an airbox mod that actually helps this bike breathe and get more power, or keep it stock?
  17. ADV-Wes

    ADV-Wes I'm not lost....yet.

    Joined:
    Aug 2, 2008
    Oddometer:
    177
    Location:
    NE Victoria (Aus).
    Anyone direct me to where I can download a Workshop Manual for 1999 WR 400F??

    (And in the meantime, does anyone now the oil volumes for this model? A mate who knows even less than me about bikes has left one a my place for me to clean up for him!:huh Oil change, new clutch, Clutch cable, de-comp cable, clutch perch, brake pads.......the list goes on...........my latest project :lol3)

    Cheers,
    Wes.
  18. yamahaman

    yamahaman wannabe bike builder

    Joined:
    Jul 28, 2010
    Oddometer:
    224
    Location:
    melbourne Australia
    The specs are the same for 426 400
    1.5 litres of oil with out filter change
    1.6 litres of oil with filter change
    1.7 litres of oil total (there is always 100ml of oil left in the bike after and oil change)

    inlet clearances of 0.10mm - 0.15mm cold
    exhaust clearance of 0.20mm- 0.25mm cold

    drive chain slack 40mm - 50mm (measured at last bolt on top of chain slider between slider and chain)

    that should get you started message me for more info

    :1drink:1drink:1drink
  19. yamahaman

    yamahaman wannabe bike builder

    Joined:
    Jul 28, 2010
    Oddometer:
    224
    Location:
    melbourne Australia
    These have heaps of power stock most of the mods are for rideability.

    Carb mods make the bike pull throughout the whole throttle action, this model was renowned for an awful bog when the throttle was cracked open hard.

    yz pipe increases responsivness Not much difference just an end cap and length I belive

    Exhaust cam is 100% for the auto decomp this helps the bike because with out the cam they used to stall all the time in the woods when you would rear brake slide into corners the auto decomp cam totally eliminated this problem, However i did notice a small power increase down lower but could be mistaken

    Keep the airbox stock.

    You can get lots of power out of these,at one stage, I had a head that was fully ported with Kibblewhite diamond coated ti valves with a prox high comp piston and had a lightened yz flywheel vortex ignition with a raised rev limiter and the bike was an absolute weapon to ride, too much to handle then I dropped the high comp piston and put the wiseco 450 kit in it and then it was worse. All this pursuit for horsepower just ended up costing a bomb because I destroyed two complete heads. I have put nearly everything back to stock, kept the vortex ignition because it has two settings max tourqe (slippery conditions) and max power and it never comes off the max tourqe setting.

    I was at an enduro and an old racer said dont spend money on motors spend it on brakes, tyres and suspension then go learn to ride. So I heeded this guys wisdom went to some riding schools and now brake much later and carry more corner speed and still round up most on the track and trail. Guys with the new bikes (especially the 16yo's) hate it when they get passed by a fat guy on a ten year old bike bike with a bad rep for being too hard to ride.

    Try this carb setting (may not work real well in US)
    standard yz needle (3rd from top clip)
    38 pilot jet
    165 main
    1 3/4 - 2 turns out on the air screw

    Bear in mind I have my bike running quite lean and I have tried the jd jetting kits and there recomended settings are way too rich for our fuel quality (quite a lot of setting on american forums dont work real well in Australia dont know why)

    :1drink:1drink:1drink
  20. ADV-Wes

    ADV-Wes I'm not lost....yet.

    Joined:
    Aug 2, 2008
    Oddometer:
    177
    Location:
    NE Victoria (Aus).

    Awesome mate, thanks a heap, EXACTLY what I was after - no need for a manual :clap

    Cheers.