Yamaha WR250R Mega Thread

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

  1. Kuttula

    Kuttula 2011 WR250R, 2005 KTM 250 EXC, 2007 DRZ400SM

    Joined:
    Jun 13, 2011
    Oddometer:
    240
    Ya, when I bought the kit I measured the ring gap, when I did this I swear I noticed that the cylinder looked a little oval. I figured it wasn't a big deal, and it was probably my imagination. This guy seemed reputable so I trusted it was OK. I didn't take any measurements on the cylinder though. After I installed it and it failed he mentioned his good Cylinder guy had left and his son had done the work on mine. I had sent him back the busted one, assuming he might replace it, but he wanted to charge me for new stuff. No way, not after it had just failed so bad... So I just bought some used stock stuff on Ebay for cheap. Kinda wish I had taken a measurement on the busted one before sending it back for my sanity on this matter. The piston had partially seized, scoring the crap out of everything. It was running, but with really bad piston slap. I can't help but partially blame myself though, after it failed when I drained the oil I noticed it was severely low. This was surprising because I had only gone 500 miles since changing it... though thinking on it now, I did ride home another 5 miles after it had its seizure it could have eaten a lot of oil in that time, as the seals would have been pretty messed up. It failed as I was going WOT up a big ass hill. This was at 1500 miles so I was sure that I was broken in all the way. This was actually also the first time I opened it up to its max and held it there. I was watching the mph climb and at 98 or so, it very suddenly felt like it was running out of gas bad, I cut the throttle and immediately started loosing speed very fast. I reopened throttle to about half way and was still loosing speed hard, but it leveled out at around 40mph which I kept it under until I got home. This happened back in June of 2015 I bought the stuff in like Jan 2015.

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  2. raptortrail

    raptortrail Been here awhile

    Joined:
    Jun 12, 2010
    Oddometer:
    350
    Location:
    Washington,Il USA
    Yea when I called to ask about the kit he told me he sent the cylinders off to be bored and plated so I just bought the piston-rings and gaskets. The piston was a very nice CP piston and I sent the cylinder to Millenium tech in WI. They have done excellent work for me in the past and have a quality control department that inspects all work before it is shipped back. If there is even the smallest problem when you put an engine back together it will bite you in the a$$. And I mean $$$$$
    Bitingdog likes this.
  3. advmgm

    advmgm Long timer

    Joined:
    Feb 21, 2013
    Oddometer:
    2,308
    Location:
    Omaha Arkansas - Motorcycling Paradise
    O ring chains don't need lube - they just need to be clean so the grit doesn't eat up the O rings.
    WD-40 cleans that grit off. I use it or a Silicone/Teflon spray.
    rsteiger and Migyver like this.
  4. inroads

    inroads Go West old man

    Joined:
    Feb 12, 2010
    Oddometer:
    848
    Location:
    Hye,Tx./ Grand Junction,Co.
    ^^^ I buy WD 40 in gallon cans for about $19 and it goes along way.

    I douche and saturate the chain while rolling the tire until it’s dripping off.

    Then I wipe it clean with rags.Looks clean,won’t attract dirt and the O-rings stay nice and supple.
  5. Stillwater97

    Stillwater97 Been here awhile

    Joined:
    Oct 5, 2014
    Oddometer:
    114
    Location:
    Bend, Oregon

    +1 I've done everything possible as well. 306cc of pure radness. I did it because I wanted to and because I could. It's got more everywhere, and I still like it on the highway a whole lot more than a dirtbike with lights. The point is, well there isn't one, just go ride the shit out of your bike.
    rsteiger, davidp14 and greenboy 667 like this.
  6. Jollyrogers

    Jollyrogers Long timer

    Joined:
    Aug 31, 2015
    Oddometer:
    1,061
    Location:
    Ladysmith, Virginia
    Whelp my “new” bike is in the shop for the stator recall. The ride there was fun, all the rain we had meant there were several water crossings (flooded roads) going the back way. I realized my wife stopped following on the second one as it was deep. So I turned around and found her trying to turn around and we rerouted. Got on the highway and got to see how gutless the bike was too. Had to really ring its neck to get on at a good clip. LOL. Definitely not my 640.

    In the meantime shopping tires, 90/90-21 MT21 up front, and I’m guessing a 120/90-18 D606 on the back unless someone has a better recommendation. What’s the consensus on gearing when moving to this tire as I think it’s taller than stock, I was going to go 13/48, any opinions of peeps with experience?
    davidp14 likes this.
  7. Bitingdog

    Bitingdog That's not my dog

    Joined:
    Apr 2, 2015
    Oddometer:
    9,760
    Location:
    Vancouver B.C. rainforest
    I run 14x52 sprockets which is almost an identical ratio to 13x48. Great do it all gearing imo. For DOT knobbys try Motoz Enduro IT front and rear. The rear howls a bit around 40-45 mph, but it quiets down substantially at freeway speeds. D606's are actually far noisier at 60+mph. I don't like Pirelli mt21's on lightweight bikes! They wash out on dirt & gravel without any notice. Very sketchy:(
    rsteiger and Jollyrogers like this.
  8. Jollyrogers

    Jollyrogers Long timer

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    Aug 31, 2015
    Oddometer:
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    Ladysmith, Virginia
    Thank you for that feedback bitingdog. I’ll look into them. RMATV is the only dealer in the US?
  9. max384

    max384 Bandaided

    Joined:
    Nov 23, 2011
    Oddometer:
    4,767
    Location:
    Eagle Rock, PA
    I had a bit ou free time tonight to tinker with the bikes. I replaced the piddly stock toolkit with something that will actually hold enough tools to do most trailside repairs, including tire repair.

    [​IMG]

    [​IMG]

    I removed the stock tool kit and dremeled off the brackets. The tool tube is a tractor manual tube. I ground off the plastic mounting arms, as they don't mount to a subframe well, and just get in the way. I also filled in the breather hole with epoxy to keep it waterproof. The metal bracket is an exhaust mounting bracket. I then cut out a piece of galvanized sheet metal I had lying around, drilled holes in it that matched the exhaust mounting bracket holes, wrapped that around the subframe, and then bolted it all together. Works like a charm.

    Here it is compared to the stock tool kit, for a size comparison:

    [​IMG]
  10. Bitingdog

    Bitingdog That's not my dog

    Joined:
    Apr 2, 2015
    Oddometer:
    9,760
    Location:
    Vancouver B.C. rainforest
    I got them from Fortnine, then saw them on sale for less at the local KTM dealership
    Jollyrogers likes this.
  11. rsteiger

    rsteiger Bob

    Joined:
    Jul 2, 2011
    Oddometer:
    926
    Location:
    Hotlanta Area
    I think the general concensus on gear is that the bike as stock is geared to damn tall. Many initially change out the front sprocket from a 13 to 12 tooth but some have seen that lead to increase slider wear.

    I myself run 13/48 and it seems to do pretty well overall. My gearing logic is if I can pull my max speed in 6th gear without having to downshift into 5th then I have the gear matched to the power curve pretty well. I probably will give 13/47 a shot in the near future since I have the sprocket for it. The link below has pretty good information as far as ratios with different sprockets and chain length required:

    http://wr250rforum.forumotion.com/t5-chains-and-sprockets

    For tires, well that all depends on how good you are at changing them and how/where you ride the bike. The MT21 front and 606 rear is a pretty good overall combination for mix use. In my experience the front tire is more important than the back tire for the riding I do. I generally will only run a MT16 or XCMS front tire since they tend to hold a pretty solid line in the sloppy/loose stuff. I think the MT16 is probably a little bit better on pavement than the XCMS but both wear out pretty quickly when on pavement. If you are running a 606 rear you may go through two fronts (MT16 or XCMS) depending on how aggressive you brake and pavement you ride. With the MT21 I think you are about 1 for 1 but you give up some of that dirt performance. Again it all just depends what defines value for you.
    Bitingdog and Jollyrogers like this.
  12. Bitingdog

    Bitingdog That's not my dog

    Joined:
    Apr 2, 2015
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    Location:
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    H5qz2
    I like the Pirelli XCMS, XCMH, and MT16. Still hate the mt21 though, LoL
    Yinzer Moto and rsteiger like this.
  13. greenboy 667

    greenboy 667 Keep your bloatocycle - I want a PR7!

    Joined:
    Apr 28, 2013
    Oddometer:
    937
    Location:
    remote mountain cabin in Montana
    I don't mind using 5th on the highway when it gives more oomph up grades, especially when headwinds are present. Just like I don't mind it when I'm going over a pass in a cage and the gears do better one gear lower to keep to a speed I consider practical. That's what the gears are there for.

    A lower-ratio WR seems to go just as fast as the stock gearing on varied roads since the biggest factor is aerodynamics and mechanical drag versus how much power is actually available. To a certain threshold it doesn't even seem to affect fuel economy adversely. But the real factor is 1st and to a lesser extent 2nd gear: are they low enough to ride tight off-road and hill-climbs. I found with a larger diameter rear tire that 13/47 or 50/14 are as high a ratio as I would ever want, borderline perhaps... for stuff that is more challenging one could stand to go a lot lower yet.

    The stock ratio sucks even on stock-like tire diameters (unless maybe you live somewhere where there is hardly any wind or elevation changes and stick to pavement).
  14. Kuttula

    Kuttula 2011 WR250R, 2005 KTM 250 EXC, 2007 DRZ400SM

    Joined:
    Jun 13, 2011
    Oddometer:
    240
    I run 14/48 with a 112 link chain. This is just slightly lower than stock. I ride freeway often so it works well for me this way. I only just wanted to take the edge off when starting from a stop on a hill. I used to run 13/47, this felt like a half step down, so 1st felt like .5 and 2nd felt like 1.5 compared to stock. At first I liked this, but after just a few months as I got faster 1st started to feel useless for anything, but then 2nd was both too high for technical and too low for cruising. I think what you run really depends on rider preference and average speed and the type of terrain. I run D606 tires and tubliss system. I run the D606 in the front too, only because the last few tire changes I was setting up for a long freeway to dirt trip and wanted the longevity. The D606 front lasts longer than the Mt-21. Though I will probably keep running the D606 front with the tubliss system installed as I like having the super tough sidewalls. There is no chance a rock is gonna poke through them, and if it happened the tire is so tough it doesn't really matter running at 0 PSI. For tubes though, I do remember the MT-21 front seemed to hook up better and was more predictable. Lastly I think that when the MT21 front starts to get worn down it gets shitty fast, where the D606 front holds out for longer. This is the opposite for the D606 rear, I usually dump them after 2/3 of the tread is gone, or about 2k miles. After that its just shit off road, even though it has like another 1k miles left to go on it.

    I just remembered I have mad Hype for the new Metzler MC 360. I am really excited to try this tire next, it is cheaper than the D606, and I think it should be better off road, while still being ok on the freeway. That might be a better fit for me as off road is my main focus, the freeway just gets me to where I am going.
    Bitingdog and rsteiger like this.
  15. advmgm

    advmgm Long timer

    Joined:
    Feb 21, 2013
    Oddometer:
    2,308
    Location:
    Omaha Arkansas - Motorcycling Paradise
    i run 13x48 with the MT21 and D606. For the type of riding I do around here its a very good combination. Never had the MT21 wash out or even slide on me and the D606 has all the bite I need to go up or through anything I should be trying...
    Bike has much better low gear tractability for those 1st or 2nd gear switchbacks that are full of 2" loose rocks and will happily run 60-65 all day long. 6th gear is actually much better with it on the highway.
    Bitingdog, rsteiger and Jollyrogers like this.
  16. sperduton

    sperduton Been here awhile

    Joined:
    Oct 29, 2003
    Oddometer:
    547
    Location:
    Lebanon Township, NJ
    That's a pretty sweet idea. I've been trying to figure out where to carry other tools since I don't want a tail bag.

    Sent from my XT1585 using Tapatalk
    max384 likes this.
  17. KICKNBACK

    KICKNBACK Old enough to know better young enough not to care

    Joined:
    Oct 16, 2012
    Oddometer:
    875
    Location:
    THE 949 Cancer Sucks!!!!!
    It's a Yamaha, you only need tire tools if it breaks that bad out in the sticks you won't have the parts to fix it anyway and will just throw all those tools at it cause your mad.:rofl:imaposer

    Really, basic small tools or just spend the money on good Sat phone or locator because are you planning on replacing the top end doing a tear down to fix a shift fork,clutch?why the need for so many tools? point is you can only do so much in the dirt without oil, gaskets, yamabond, torque wrench if it's that bad you have to tear into it that deep chances are you wont have the parts to fix it out there.
    PlowHand likes this.
  18. SMIFFXC

    SMIFFXC Been here awhile

    Joined:
    Mar 23, 2012
    Oddometer:
    243
    Location:
    Maine
    Funny. The only thing I have ever had go wrong on one of my WR's was the clutch cable on my 450 broke. And no, I did not have a replacement....but I do now in the tail bag tool kit on both. My tail bag has the tools and my son's has a small first aid/survival kit (we use for hunting too). You just never know and it is really more to make me feel better and maybe teach him to try and be prepared. :)
    Bitingdog likes this.
  19. KICKNBACK

    KICKNBACK Old enough to know better young enough not to care

    Joined:
    Oct 16, 2012
    Oddometer:
    875
    Location:
    THE 949 Cancer Sucks!!!!!
    That's my point how many tools did it take to change that cable 8mm 10mm couple allens you don't need a Snap-on rollaway on your tail rack
  20. KICKNBACK

    KICKNBACK Old enough to know better young enough not to care

    Joined:
    Oct 16, 2012
    Oddometer:
    875
    Location:
    THE 949 Cancer Sucks!!!!!
    Also if your going to carry an extra cable with you take the time to zip tie it to the cable your using that way when the cable breaks you can just adjust slack pull the old ones ends out put the new ones end in and adjust it up then you don't have to disassemble your bike out there cause you thought ahead in the comfort of your cozy garage.