Yamaha WR250R Mega Thread

Discussion in 'Thumpers' started by Sock Monkey, Apr 7, 2008.

  1. Chadx

    Chadx my toot toot

    Joined:
    Oct 29, 2007
    Oddometer:
    2,170
    Location:
    Bozeman, Montana
    Honestly, I just keep it where it seems about right. When the bike is on the kickstand and I push up on the bottom of the chain, I can push it up a bit over 1/2". Once it gets over 3/4", I adjust the chain. Note that even when I stand the bike up, it's own weight make the butt sink (I have very low preload set) and checking it with it holding up it's own weight or with me, it is pretty tight. I'm due for a chain guide and have one laying here, but haven't swapped it yet. I have a total of 8,000 miles on the bike and about 3,000 of that was with the 12/43 combination. (I think I said 2,000 before, but he more I thought about it, I realized it was much longer than that because I didn't get my 13/48 installed until around 7,000 miles).

    Am I running it too tight? I don't know. I guess we'll see if it causes any issues, but so far, so good. The stock 43 tooth was starting to wear at 7,000 miles when I swapped it, but I could have run it for a fair amount of time longer I think.

    I think most people adjust the chain to about the right tension, but then wait too long for the next adjustment. Accelerated wear seems to occur during that "I'll get to it soon" period.
  2. SheWolf

    SheWolf Under Your Bed

    Joined:
    Oct 26, 2008
    Oddometer:
    629
    Location:
    Vermin BC, Canada
    Procrastination can be nasty. I got into the habit of checking chain and tires before I leave a long time ago. No different than doing a pre-trip on the truck before heading out into the bush for a load. Easier to catch things when you're not in a rush and take your time checking stuff.:thumb
  3. scottmac

    scottmac Long timer

    Joined:
    May 21, 2008
    Oddometer:
    2,957
    Location:
    La Selva Beach, CA.
    Thank's for the camparison pics of the stock and Sargent seats
    Chad!

    I liked the look of the Sargent when I saw it and seeing it paired
    up against the stocker has not changed my mind.

    Another one to add to the farckle bucket wish list....:evil
  4. DugsGMS

    DugsGMS Adventurer

    Joined:
    Jun 3, 2008
    Oddometer:
    20
    Location:
    Cherry Valley
    I used to run 12t on the front and had no problems with wear. I now run a 13 and a 48t rear so I can just change to a 12t or 14t front depending on the ride Im going on, though 99% of the time I stick w/ the 13.

    Alot of people have alot of way to adjust chain tension but theres way too many varialbles involved in using a arbitrary measurement like 2 fingers or the like to get a accurate measurement. Everyones fingers are different. That being said, I will give what I feel is the absolute best way to adjust chain tension.

    First of all put the bike on a stand. Next, remove the bolt that attatches the shock linkage pivot to the swing arm. Next put a floor jack under the rear tire and jack it up until the front sprocket nut, the swing arm pivot bolt and the axle nut are all lined up. That is the point where the the front and rear sprocket are the absolute farthest apart. Now adjust chain tensoin so there is just the slightest amount of slack. I usually set it so if I put my thumb under the chain and my index finger on top a couple of links away and squeeze theres just a little bit of give. At that point, using the adjusters make sure the rear wheel is straight. Dont trust the markings on the swing arm or the adjuster blocks, use a straight edge placed on the face of the rear sprocket and running down the length of the chain. Next, recheck chain tension and when youre satisfied, reassemble and tighten everything up.

    Sounds like alot of work but you really only have to do it once, once the bike is all reassembled and tightened up, take the bike off the stand and feel how much slack is in the chain with the bike on its kick stand. All you need to do from then on is remember that or if you dont trust your memory measure it and from then on when ever you have to remove the rear wheel or adjust chain tension for any reason all you have to do is adjust tension to that spec with the bike on the kick stand and you have the perfect adjustment.

    Hope that helps anyone thats real obsessive like me to be able to sleep well at night knowing that youre not doing damage to the bike while riding it.

    Anyways, while Im posting here Id like to see if anyone whose fuel pump went out on them could give me their experience as I think mines on its way out. Lately my bike has been down on power, not terribly down but a noticeable amount. It feels fine at lower rpms and on big quick throttle openings but at high rpm WOT runs it feels like it runs out of steam on the top end. It doesnt fall on its face or anything but it just feels not as powerful as it once did. Also, once in a great while itll stumble or surge and once it got so bad thet it had almost no power, would stall at every stop and was real hard to start. When it did that I shut it off, let it sit for a few, restarted and it was fine and never happened again.

    I really think its a fuel problem (lack of delivery volume)and was planning on getting a new pump when I change to my big tank but was hoping that someone whose died on them could give me some info on the symptoms they experienced before theirs died. Thanks in advance.
  5. nachtflug

    nachtflug infidel

    Joined:
    Jan 23, 2002
    Oddometer:
    48,198
    Location:
    Harrys place

    appreciated. on reflection, the rides I've been on were less than enjoyable as riding was second to dealing with the ridiculously ill suited power. the tease has been in fairly rocky stuff the suspension is a real joy to experience. they sure have come a long way since 1971 :huh . Christ that bike is sweet for a "dual sport".

    Is everyone going with GYTR sprockets or just ordering WRR stuff. I really want to try the bike with what sounds like a 13/48 combo and give it another chance. thanks for the input.
  6. MoBill

    MoBill Smiles when says dat

    Joined:
    Mar 10, 2007
    Oddometer:
    13,809
    Location:
    NJ
  7. dirthauler

    dirthauler rolling rototiller

    Joined:
    Feb 11, 2010
    Oddometer:
    1,719
    Location:
    Pittstone, ya it's a Flintstones refference
    i can whole hartedly recomend renthal chain wheels and chain, that 14/52 combo i went with realy rocks! and talk about super light!?! the rear is ozs. Not lbs. And that's rotating unsprung weight, and what's that? something like 6lbs. to the hp? chassis weight wise, taking off 8 lbs. is just like adding 1 hp
  8. scottmac

    scottmac Long timer

    Joined:
    May 21, 2008
    Oddometer:
    2,957
    Location:
    La Selva Beach, CA.
    13/46 for close to 10,000 miles now. With a Renthal 46 Rear. It's just now
    starting to get some scallop visible in it.

    Chain/sprocket life all depends on the care you put into it.

    Yes, a gearing change will help. Getting rid of the EXUP and opening up
    the airbox and adding a fuel programmer will help as well.

    Let that baby breathe and you'll see a difference.
  9. MoBill

    MoBill Smiles when says dat

    Joined:
    Mar 10, 2007
    Oddometer:
    13,809
    Location:
    NJ
    Link to the rental stuff? I'll put it on the data thread.
  10. eakins

    eakins Butler Maps

    Joined:
    May 29, 2002
    Oddometer:
    20,386
    Location:
    Fort Collins, Colorado
  11. Mr. Fisherman

    Mr. Fisherman PROUD 2B Riff Raff!

    Joined:
    Oct 8, 2006
    Oddometer:
    11,063
    Location:
    Drinking from the Stanley Cup!
    140 miles of fun today....

    [​IMG]

    [​IMG]

    [​IMG]

    The more I ride this bike the more I like it :nod
  12. tremor38

    tremor38 Long timer

    Joined:
    May 30, 2006
    Oddometer:
    1,478
    Location:
    Japan
    Your bike has also been lowered quite a bit. Don't you think your swingarm might be at a different angle than OEM, thus changing the whole 'swingarm chew' equation. :ear :wink:

    Also, how much do you weigh soaking wet, tiny one?! :D
  13. tremor38

    tremor38 Long timer

    Joined:
    May 30, 2006
    Oddometer:
    1,478
    Location:
    Japan
    As long as you have the bike lowered enough to flat foot with a 21" inseam, you should be good to go :lol3 :evil
  14. tremor38

    tremor38 Long timer

    Joined:
    May 30, 2006
    Oddometer:
    1,478
    Location:
    Japan
    Could be the pump, but I'd pull it and check if there's any crap blocking the intake. Dunno if the WR has a filters on the pressure side, but that would also be worth if it does.
  15. SheWolf

    SheWolf Under Your Bed

    Joined:
    Oct 26, 2008
    Oddometer:
    629
    Location:
    Vermin BC, Canada
    Sure mine's lowered. So are others' bikes, and others who haven't lowered it that run the 12t, don't have that problem. You don't have to have it lowered with a 21" inseam and flatfoot to get away from that. Keep the chain adjusted properly is key; dropped or stock height.
  16. Pax

    Pax shazam.

    Joined:
    Jul 22, 2006
    Oddometer:
    812
    Location:
    Columbia MO
    Those of you who have replaced the o-ringon the oil filter cover, are these standard size and can I pick them up at a local auto parts store? How about the copper crush washer for the oil plug? Sizes?

    -Pax
  17. nachtflug

    nachtflug infidel

    Joined:
    Jan 23, 2002
    Oddometer:
    48,198
    Location:
    Harrys place
    I know this has been hashed over countless times but if anyone could chime in on.

    1. stock gearing is?

    2. general consensus that the stock WRR countershaft sprocket can cause the chain to jump is at this point generally considered legit?

    3. assuming yes to #2 - WRF sprockets/gytr or aftermarket sprockets are the way to go?

    4. I'd rather go bigger on the back and not go smaller on the front. with on road performance not being a major concern what is anyones best suggestions for gearing set ups front and rear. I'm not totally opposed to changing the front sprocket, and will even if I leave the same # of teeth as I've experienced the skipping/chain hopping.

    thanks in advance.
  18. Crawdaddy

    Crawdaddy Navigate 2 Adventure

    Joined:
    Jun 5, 2007
    Oddometer:
    2,296
    Location:
    Ramona, CA.
    +1
  19. Reposado1800

    Reposado1800 Juicy J fan!

    Joined:
    Dec 8, 2006
    Oddometer:
    5,814
    Location:
    5th and Main
    The goofy shaped teeth on the stock 2008 rear sprocket is what causes the chain to jump when it is on the loose side. They are pyramid shaped.
  20. Krabill

    Krabill Long timer

    Joined:
    Oct 25, 2005
    Oddometer:
    4,944
    Location:
    Tulsa, OK
    1. stock is 13/43

    2. Something with the stock setup causes issues if there is too much slack. Not exactly sure what it is, but the problem goes away w/ aftermarket gear.

    3. WRF & YZF sprockets both fit on the WRR. I'm using Primary drive gear from Rockymountainatv, but I've seen guys running every sort of sprocket you can imagine.

    4. I'm running a 47T in the rear and I'm pretty close to the chain guide on the bottom. I'm not sure how much bigger you can go without an issue. I ride on the street quite a bit and use a 13T counter, but I rode a friend of mine's with a 12/47 setup and wow, if you're just going to set it up for off-road, that was one sweet setup.