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519 Topics 5.1k Posts
  • Question about 2 stroke throttle to rpm relation

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    R

    @AndyYam
    Well i tried to take the bolt out for 4 days and nothing happened ,only on day 3 did hear the bearings crunching in there , it is rusted solid and a multiple ton press is required or something like that, i even took a rotary hammer and tried to hammer it out to no avail. The oil fittings in the swingarm look like they never been used you can't see shiny metal there at all, so out of pure despair put the bloody thing back together and filtered the oil and it stopped whining , i have a feeling its clutch plates + dirty oil.
    I changed the oil at the beginning of this season but it was grey-ish all ready looks like the gearbox won't last to long. I thought about it and decided if i can make it running for the rest of this season i will so i could clean up the garage get some tools some books/manuals, and do everything properly during the winter because i need the bike to repair the bike catch 22.

  • Tight crank shaft nut

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    AndyYamA

    I ended up using a bit of alluminium between the gears and an impact gun on the nut. A bit pikey but it did it 🙂

  • Complete Engine Rebuild Guide

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  • full engine rebuild on dt 1990

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    AndyYamA

    I know this is oldish but I assume you found the sticky at the top of this section.

  • Gearbox bearing removal methods / tools?

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    AndyYamA

    Anyone got a link to a puller they know works for the DT bearings? I'll definitly give the 160 in the oven a go so cheers for that tip. Alos heard that freezing the bearings over night helps with refitting the new fellas.

  • Carb manifold

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    NINJAN

    @maar70 said in Carb manifold:

    Ok and how do I go about find is the bikes age?

    The date of first registration should be on the V5. If you do not have a V5 you can look the details up here, by adding its reg and make;

    https://www.vehicleenquiry.service.gov.uk/

    You can then look for the correct part number on Fowlers webby, just select the correct year first;

    https://www.fowlersparts.co.uk/browser/manufacturer/yamaha/bike/dt125r

  • Power Loss

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    MightymanM

    Good to hear a simple fix!

  • clutch push rod adjustment

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    CalumC

    It's a locking nut. So provided it is sufficiently tight, it'll be alright.

    SO you adjist the push rod on the basket. THe nut behind the pressure plate and a final nut on the clutch basket itself locks off.

  • Engine rebuild guide thread?

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    CalumC

    @AndyYam said in Engine rebuild guide thread?:

    Yeah true, I just find that a forum rebuild guide with photos and advice often encourages people to dive in compared to a haynes which can sometimes appear a little over complicated and lacking in detailed photos. I followed a youtube video for the strip down and case splitting which really spurred me on. They used a bit of alluminium the lock the gears which really proved useful. to be fair i didnt even check what haynes suggested.

    Also a guide of what parts to buy and what not to buy might help. Your gearbox bearings post was great for me, but although I know not to use yambits engine oil seals and only Athena or gen head gasket, I might have been tempted.

    I'll see how I go but watch this space 😛

    Do it mate!

    Yeah it's good to fill the forum up!

  • Dellorto 28 mm carb settings

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  • Barrel differences

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    CalumC

    @Biker_123 I would go wr all the way.

  • Power valve clearance

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    Biker_123B

    @LJK_hunter You'll need to file the power valve down mate! There's a few guides on YouTube it's really easy to do. Definitely don't use the bike until you've taken care of the power valve as the piston could hit it once it's heated up.

  • YPVS adjustment problems...

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    Gt it adjusted not, dont now what went wrong, i think the black part wasnt properly seated on the valve.

    Next problem is to sort out a rich condition. Bike starts ni problem without choke, and wont rev out. Makes more power if I close the throttle a bit. Midrange is crisp after lowering the needle.

    Bike has sat for a while, but it seems all pasages in carb is clear, and the choke is working as it should.

  • Cyclinder head

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    BurridgeB

    @kennymurphy97 it definitely gave it more compression as I could feel the bike vibrated quite a lot more. Was going to get a compression tester for a before and after but forgot all about it. I hadn't ridden the bike for a good week or so before changing the head though so can't accurately say if I felt a difference in power or not, although with more compression usually comes more power. I should be getting my new exhaust soon so I can make the most of it.

  • This topic is deleted!

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  • Torquing head bolts down

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    BurridgeB

    Cheers guys, managed to use the torque wrench on all but 2, guess work with the one closest to the front part of the frame and the one next to the thermostat housing

  • Mikuni carb jets?

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    DartyD

    @Calum haha yeah rocking a VM26SS, Yam cutting corners there

  • Bottom end bearings

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    M

    Sell the rod kits on Pjme just looked pal and yeah have typed them bearings in is it just them ones and the mains I need

  • Rubber mushrooms for engine case bolts

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    CalumC

    WHat number

    https://www.yamahamotorcyclespares.co.uk/spares/epcImages/9028/9.jpg

  • What size sprockets on super moto wherls

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    M

    @Calum off topic here don't suppose you know the bearing codes for the 4dl bottom end can't find them anywhere