WR 250 supermoto project

Discussion in 'Super Moto' started by Dan131.2013, Jul 28, 2021.

  1. Dan131.2013 Husqvarna

    Husqvarna Motorcycle:

    After lots of searching there is not a massive amount of wr250 supermoto's so thought i would start a thread on my project bike.

    Got the bike as a tired enduro bike. Stripped the bike down to the frame to do a quick few coats of hammerite spray just to freshen it up (Would not recommend hammerite spray - very thin and runny)

    Engine had a complete strip down. New main bearings, seals, con rod kit, piston kit (Standard size - piston B from memory) Surprisingly a very easy engine to work on, very simple.

    New OEM inlet rubber installed as old one had perished. Apparently a common problem.

    Talon / excel wheels ordered. Nearly went with Warp 9 but import tax was too much of a risk.
    5" rear rim with a 160 tyre. Veryyy tight to get into the swing arm but does fit. Hopefully wont get any chain slap on the rim.
    I dont plan on swapping my wheels very often but if i was - defiantly would have gone for a 4.25" rim.

    Lots of other bits and bobs done along the way such as fork seals / chain and sprockets (15 x 38 gearing with non o ring chain to give as much clearance as possible)

    Attached Files:

  2. Dan131.2013 Husqvarna

    Husqvarna Motorcycle:
    Before and after shots of exhaust. Compressed air and oxy acetylene torch

    Attached Files:

  3. Dan131.2013 Husqvarna

    Husqvarna Motorcycle:
    And a final photo of the bike - nearly ready for its MOT.

    Need to do a few more little bits, connect up all the lights, tuck wiring and check everything works as it should.

    Also need to check the timing with a strobe light as i am currently relying on the casing mark / flywheel back plate mark which is not very accurate

    Attached Files:

  4. Hurky Husqvarna
    AA Class

    Husqvarna Motorcycle:
    WR300 2010
    Other Motorcycles:
    Yamaha WR480F 2008
    That looks sick, I always wanted to try a SM kit, but never did for two reasons, I don't really stop riding offroad during the year, it really depends on the weather, but this year for example keeps raining during the summer and temperatures are not that high so we still ride ... and the second point is cost as the wheel set's are not that cheap.

    A few years ago I tried a GASGAS SM from a friend, it was nice, but dangerous as the forks where not touched and were very soft, during front braking it want to dive way too much into the ground and can be sketchy :D Are you planning in adapting the suspension settings ?

    What gear ratio are you running ?

    Dan131.2013 likes this.
  5. Dan131.2013 Husqvarna

    Husqvarna Motorcycle:
    If i lived in spain i would probably keep the enduro wheels on too! But here in the south of England it's a bit over populated and it's hard to find places to ride without trailering the bike around :(
    Luckily I done quite well with the supermoto wheels. They come up cheap for a husky 125 so i did have to machine new spacers for them - it involved some trial and error to get them spot on.

    Suspension wise, i might do some adjustments but my current plan is just to get it on the road and see how it feels. I haven't had a 2 stroke supermoto so no point going to mad at the moment incase i don't like the feel of the engine :o

    The gearbox is just the standard 5 speed box, so im hoping the sprockets i have gone for (15/38) will help with the higher road speeds. These sprockets were recommended from other peoples with wr250 supermotos. I have only ridden it up the road in 1st gear, and 1st gear felt very tall - required a lot of clutch to get moving which i expected.

    I had everything bolted back on the bike ready to book an mot - but when i started it, none of the lights work and the resistor which is under the tank has melted its heat shrink.
    So i'm not sure if i wired something up wrong or the resistor has just died.

    OEM resistor is £40 and a 2 week wait, so i have ordered a 10W 27 ohms resistor of ebay for £2 and i'm going to try make my own.
    But in the mean time i'm going to cut the resistor out and splice the wires together to see if the lights work (I will start the bike with the lights on - as i found a previous post from you Hurky saying you have removed your resistor with no problems, but your lights are hard wired so they're always on)
  6. Dan131.2013 Husqvarna

    Husqvarna Motorcycle:
    So turns out i had the wiring connected up wrong.

    The resistor heat shrink is melted slightly - but it was when i got the bike so i think its got warm at some point in the past, but does seem to still work.
    I have hung it out from the bottom of the tank, rather than under the tank so i can keep an eye on it. It will also get better air flow to keep it cool.

    For anyone looking for the correct wiring for the yellow wiring circuit for the lights, the following seems to work. I was struggling as the colours didn't match the wiring diagrams i could find online. Mine is a UK bike if that makes any difference.

    So the yellow wire coming from the generator (Female space) connects to the Yellow wiring with the inline resistor built in (Male spade)

    The female spade on the yellow wiring with the inline resistor built in connects to a single red wire with a male spade that comes out from the main loom (Which comes down from behind the headlight)

    The single yellow wire that comes off the regulator with a male spade (Finned metal block bolted to frame) goes to a green and black wire with a female spade which again comes out the main loom (Again comes down from behind the headlight)

    All wires with a ring end connector are earths... i think they can be bolted to any part of the frame (Make sure paint is scraped off so i makes good contact to metal)

    Hopefully that all makes sense and can help someone out in the future. I have added a few photos which might help

    Attached Files:

  7. Dan131.2013 Husqvarna

    Husqvarna Motorcycle:
    Right, bikes passed MOT, but kept cutting out all the way there and back.

    Seems to run perfect when its cold. But once hot keeps cutting out, sounds like its losing its spark.

    Haven't investigated yet, but assuming its the coil, cdi or stator :banghead:
  8. Dan131.2013 Husqvarna

    Husqvarna Motorcycle:
    Running problems turned out to be something pretty simple!

    Put a new coil on as they are only £20. No difference. Checked the resistance of the stator, and everything looked fine.

    Turned out the float level in the carb was wrong and must have been started of fuel :banghead:

    Now running pretty well. Has a slight splutter at wide open throttle which i'm hoping is main jet too small but need to investigate.