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Technical Zone

1.3k Topics 11.5k Posts
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  • Suspension Related
    100 768
    100 Topics
    768 Posts
    HOTSHOT IIIH
    @reudtr88 The seller is right, the spacers and caliper bracket are narrower than the DT125R versions. The bench mock-up in the pics above comprised a 3ET DT200R swingarm, caliper hanger and spacers mated to a DT125R hub. As you can see the 428 sprockets lined up quite well (I also had to use a 3mm thick M20 washer between the caliper hanger and swingarm to get it as good as it could possibly be with the items I had to hand).

  • Exhaust Related
    64 569
    64 Topics
    569 Posts
    D
    as far as i m aware there are 3 different types of tzr the first model series 2 (RR) an tzr125r sp i have an exhaust with the code 4DL E46 10 20 what model is it intended for

  • Framework Related
    86 606
    86 Topics
    606 Posts
    CalumC
    That's normal. All DTs are like that. [image: IMG-20251011-114625.jpg]

  • Wheel Related
    83 748
    83 Topics
    748 Posts
    K
    @Rallyfinnen I'm mainly worried about the fork sitting incorrectly resulting in leaky fork seals. The bike handled good but the seals did go out and I rebuilt it. How can I check if the wheel is perfectly centered?

  • Electric Related
    265 2k
    265 Topics
    2k Posts
    CalumC
    I'm sure someone here will be able to point you in the right direction. What we've been seeing in recent times are a lot of DTRs being imported from Europe, these can come with subtle differences, this may be the case here. This is the 3NC wiring diagram. [image: 52172141696_84e3b69382_b.jpg] I only have a Haynes manual so can't speak for what other diagrams look like. I have also hosted the workshop manuals here: https://dt125r.co.uk/topic/3258/yamaha-dt125r-200r-workshop-manual https://training.dt125r.co.uk/files/Yamaha_DT125_Workshop_Manual.pdf This may be useful.

  • Brake Related
    68 453
    68 Topics
    453 Posts
    CalumC
    Yeah that sounds like a good idea and should be easy to swap the wheels over without too much faff!

  • Engine Related
    545 5k
    545 Topics
    5k Posts
    H
    Got it, thanks for your help everyone. Was planning to have a go but then had an episode and ended up in hospital. Now I'm back in the game.
  • C

    DT125 R(4BL) Parts no longer available (new)

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    0 Votes
    1 Posts
    930 Views
    No one has replied
  • G

    Tacho reading 1500 when engine not running

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    0 Votes
    3 Posts
    734 Views
    G
    Hi, okay, thanks @declan - may try and get it open , knowing there will be a backup plan!
  • B

    Dt 125re No power.

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    0 Votes
    4 Posts
    802 Views
    declanD
    @Baileyboy2008 well like Calum pointed out there’s no such thing as pinning your valve half way if the valve is have way closed you will get zero power above 6k open her all the way and then see what it does
  • DartyD

    The Library

    dt125r dt200wr wr200
    5
    5 Votes
    5 Posts
    2k Views
    NottsbikerN
    Yes very rare now and you have to hunt high and low to find anything at sensible prices I'm afraid
  • D

    Dtr 125 pressurizing problem!

    9
    0 Votes
    9 Posts
    2k Views
    CalumC
    Pressure Cap! I wouldn't believe it but I have seen it a few times. Always start off with something cheap and look at the more expensive items later.
  • Ryan FR

    Bike lacks power

    27
    0 Votes
    27 Posts
    4k Views
    CalumC
    @Oisin You tried searching? https://dt125r.co.uk/topic/578/derestricting-guide
  • B

    Still no spark on my DT125RE

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    0 Votes
    9 Posts
    1k Views
    CalumC
    Measure across the pick up sensor. Make sure that you are getting current to trigger the CDI. You will want to follow that pulse from the pickup to the CDI. From the CDI you will see it go to the primary coil. From there it should go to the secondary mutal winding and out to the HT lead. It's as simple as that. Somewhere you are losing that signal.
  • riley_racerR

    Stickers/Decals

    14
    0 Votes
    14 Posts
    2k Views
    riley_racerR
    @oldman just had a quick search, looks ideal, cheers mate :+1:
  • V

    Why does it do this?

    7
    0 Votes
    7 Posts
    1k Views
    V
    @markus-w thanks
  • V

    Should theese jets fit my yamaha dt 125 x 2006 witk mikuni tm28-92 carb (stock carb)

    1
    0 Votes
    1 Posts
    498 Views
    No one has replied
  • J

    Dt125re 2004 servo

    servo
    11
    0 Votes
    11 Posts
    2k Views
    C
    so @Jgb19830 did you fixed it,just by that? i have the same problem.
  • 2

    This sounds like bottom end bearings right?

    4
    0 Votes
    4 Posts
    667 Views
    CalumC
    Well you should have checked the bearings at the same time. For up or down play.
  • W

    HID headlight conversion

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    0 Votes
    6 Posts
    911 Views
    NINJAN
    @ward4014 Just fit some brighter bulbs for a super easy and cheap upgrade; https://www.ebay.co.uk/itm/2-x-H5-P45t-Birnen-Halogen-Auto-Lampen-6000K-60-55W-Xenon-Weis-12V/362660604593?hash=item547041aab1:g:GEkAAOSw~dJdNZD9
  • W

    New piston but no rebore

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    0 Votes
    4 Posts
    889 Views
    W
    Thanks guys I'll take it to the shop once I have it off I'm only changing the piston because I have never changed it it rides mint but just peace of mind
  • W

    How does the oil get into the gearbox side of the engine

    5
    0 Votes
    5 Posts
    868 Views
    W
    @Calum I have had the clutch cover off everything looks good tbh
  • W

    Reset milage to 0

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    0 Votes
    4 Posts
    751 Views
    CalumC
    My aftermarket clocks reset to zero. Now my mot history is all over the place. I don't intend on selling the bike so makes no odds to me. Would be nice to see how many miles I have done in ten years though.
  • P

    General maintenance

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    0 Votes
    7 Posts
    1k Views
    CalumC
    @panmil92 I don't recall there being any certain type of weak point. Fairly bullet proof motors. It's just general items. Bearings, bushes and seals.
  • J

    Piston play

    2
    0 Votes
    2 Posts
    566 Views
    J
    https://youtu.be/p5XOQFRJzko Here it is running... Story is it overheated on a ride out due to an airlock in the cooling system. So the piston went pop
  • S

    2007 dt re blue frame colour code??

    3
    1 Votes
    3 Posts
    915 Views
    declanD
    @Minia I believe it’s on the frame tube under the rear of the mudguard
  • D

    reeds confusion ??

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    0 Votes
    5 Posts
    889 Views
    D
    @Calum said in reeds confusion ??: @Dingle74 I'm sure there is information on here about what can be used. Try using the search bar.. good pointe with the searchthing , but the searchfunction is not my new freind :crazy_face: when searching for reeds i get everything from pics of cracked seat to chain and wheel-questions :face_with_hand_over_mouth: so have just skimmed over lightly there was one post though sayin that wr dont fit and poster wanted to show a pic of the difference but sadly it didnt work for him