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504 Topics 5.0k Posts
  • Unburnt oil from ypvs housing

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    @waale2004
    Check your plug colour. I’m guessing you are running rich with a wet black plug. Cause at 50:1 all your oil is being burnt/used. It can only be excess fuel...

  • Messed up on my build need radiator advice

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    @calum said in Messed up on my build need radiator advice:

    @dan28 And the filler side is a lot thicker.

    If it's thicker that's good it has a thicker core so will cool it better

  • Coolant loss

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    @calum

    I’m gonna have to check it out. My brand new Athena gasket, correctly torqued down, blew again ☹️ Did about 100miles. Weird thing is that the bike ran the best ever after it let go. Crisp rev definition, no bogging down. I’m gonna have to compression test the engine next time. What range is good/normal!?

  • 2 stroke oils?...

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    NINJAN

    @spookdog I always use Silkolene products, their Comp 2 plus is excellent oil. I also use their grease, coolants and gearbox oil. They are all excellent lubricants and are the go to brand for me.

  • Cheap Cylinders

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    Hey
    I’m looking to get the bike up and running again for the summer and I’m wondering if anyone is selling a cylinder for a 2005 Dt125. Ideally with piston and pv, all good to go.
    Thanks guys
    Oisín

  • Pv pins

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    CalumC

    @forgotten just google dowel pins and see what comes up.

  • DTR throttle cable help!

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    @perky there are two types be careful, one has a round splitter box and one is oblong that is the later one, the problem arises when the oil pump cable goes into the housing and you try to fit the retaining clip and it’s the wrong length.

  • 0 Votes
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    rking7888R

    @spookdog
    I have no idea how it would have got broke, my only idea was a previous owner thought they new what they was doing trying to adjust it lol All the pre servo powervalve covers seem to have the pin I had a nightmare finding one NOS as the part numbers changed multiple times but turned out they all superseded each other and were the same. Will post a pic of the broken one the weekend hope this all helped tho as it was driving me insane, I was convinced it was carb problems or that my air box was blocked or something as it randomly started after a very muddy day in the woods .

  • Leaking from front sprocket

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    DTleeD

    @calum perfect cheers didn’t think it would be that simple 👍

  • Ceramic Bearings

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    CalumC

    @llldennis I think the engine is suitable reliably without needing ceramic bearings.

    The main thing to wear are the piston rings and and wall etc.

  • Chain types

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    CalumC

    @ninja I always went with Tsubaki Chains (Jap 🇯🇵 )
    https://www.bandcexpress.co.uk/pages/news/latest-news-and-offers/tsubaki-chain---in-all-sizes.htm

  • fitting later engine cases to older engine

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    @spookdog said in fitting later engine cases to older engine:

    @dan28
    I didn’t know that there was a plastic side case, but if it has the same pumps it should be ok. I’d keep my original oil pump if it’s good. Just cause it’s calibrated right.

    89 cases are plastic the later cases are alloy
    The oil pumps have a different part number not sure about water pump.

  • bike hard to start when hot, can anyone help?

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    Carry a plug spanner and the next time it happens shut off the fuel and remove the plug, then kick it over ten/ twenty times to clear it. If it starts ok let us know...
    Also try putting the old plug back in, could be a defect...
    I’d give the reeds an eyeball as well, just to check they’re closed...

  • Parts

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    @jonne123

    You can put it in from the side.
    Just lever out a bush, or put a screwdriver in one side and tap out the other...
    You shouldn’t t need to split the cases. Just lift the engine up in the frame till you have access...

    Edited for feckups 😐

  • Different power valves

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    NottsbikerN

    As mentioned the diamond shape fits the pulley with the square / rectangular end as well

    The grooves in the power valve aren't for O-rings, instead these fit into the ends caps as you cant refit the valve into the cylinder with O-rings in the grooves 😉

  • JB Weld Crankcase Fix

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    NINJAN

    @jimmydc98 As @jimmydc98 says you would be far better off getting it TIG welded, as that would be a much stronger and more durable fix. I've used several JB weld epoxy's / adhesives and have never found them to be any good. They do not seem to stick or repair stuff as stated, so I would steer well clear of them. I have tried this stuff tho and can recommend it;

    https://www.ebay.co.uk/itm/VersaChem-Steel-Weld-Epoxy-Black-2hr-Set-25ml-47709-VC-Automotive-Industrial/362460351914

    The TIG welding would be your best bet tho IMO. 😉

  • Gearbox failure

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    CalumC

    @jimmydc98 Cheap 😍

    That's good to know at least. Connecting Rod for my RS is that price alone 😛

  • Top end rebuild problems :( please help!

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    Sorry for the mega late reply on this lads, sacrificed internet for the rebuild at the time and just wanted to say (now i remembered :P) Thanks so much for all your help. got it sorted with the loctite in the end and it all worked out! really grateful for the replies. will post some bike porn soon and start getting active! 🙂

  • Engine bearings

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    NottsbikerN

    @calum

    Yes found that out to my dismay once - think they are 1mm narrower than the nearest commonly available bearing.

    Why wont these casings go back together.....

  • Hmm now what (A Rebore!)

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    @calum old thread mate but can you use a 4fu head on a 3mb barrel? ive got a 3bn head on atm and wondering what my best option is and how much more power will i gain from a 3mb/4fu head