TDR 125 19XX


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    Went and picked this up today for a pretty good price.

    Sale included everything for the bike, minus the rear wheel, sprocket, brake disk and spindle, the carb, and the power valve. Although at this point I have yet to see the ignition barrel. It could be among-st the big box of bits I was given but haven't been through it all yet. I was also given another wheel in the sale but I'm not really sure what it is from. Funny looking thing.

    Engine wise, straight away noticed a big hole in clutch case

    And although it turns over freely, I can hear a small scratching sound inside so I'll probably open it up and give it a check over. It's a 3MB.

    https://www.youtube.com/watch?v=BSjHsdnAmAs

    A good look up the exhaust port shows the state of the piston.

    https://www.youtube.com/watch?v=r_rR9Tm3jGc

    Lovely looking front wheel setup!

    The rear is Brembo too!

    Previous owner said he bought it a while back as a project and that the chap he purchased it from imported it from France, and had it registered on the Nova system. So I am hoping to get it registered here fairly easily but It probably will turn out to be a nightmare. In reality it seemed as though the guy I bought it from just wanted it so he could take a couple of bits from it... But at £200 I can't complain!

    Have to get one of my other bikes sold before I can really get started with this, but I'm not too sure whether or not I will just break it on eBay and hopefully get a bit of profit from it yet.

    Posted a separate thread asking but no reply yet, anyone know if this frame is the same as an older DTR frame? I have considered just selling the plastics for this and turning it into a supermoto DTR!



  • That Mag wheel is a TZR/TDR Mag Wheel.

    That front wheel looks to me like the Belgarda 3SH wheels which are lovely. My two pence would be to find the rear 3SH Wheel because they are lovely wheels.

    http://www.ebay.co.uk/itm/YAMAHA-TDR-125-3SH-FRONT-WHEEL-AND-DISC-/272255472336?hash=item3f63b0d2d0:g:rMsAAOSwUfNXR1IJ

    Just to give you an idea.

    The mag wheels are more common.

    Looks like a cool project!


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    I hardly hesitated when I saw what looked like the correct rear wheel on eBay just minutes after posting this!
    http://www.ebay.co.uk/itm/322112811632
    Thank you for confirming!



  • @MIGHTYMAN Nice project mate! Did you get the nova registration number with it? as you'll need to provide the dvla with the number when filling out the v55/5 registration form! Think it should be easy enough so long as you have the bikes reg number it should show up on there system along with nova being payed. Looking forward to see you rebuild it bargain price to 😃


  • Global Moderator

    I actually didn't get the Nova number or the reg number but I will be contacting the owner who imported the bike so hopefully I'll be able to attain it from him! Won't the DVLA give me a new reg?



  • @MIGHTYMAN Yes they'll give you a new reg when I done it I had to give them the old foreign log book and the nova registration number and pay a £55 reg fee and it was done but you may need to supply them with a dating certificate as well as the nova number if you don't have a foreign v5 as they're funny like that and may want to Q plate it after inspecting it but definitely a good idea to get in touch with the person who brought it in to the uk mate.


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    I will have to write a letter to the importer if I can't get his email, as I do have his address. DeeTeeMX does have a couple of different DT carbs but I've no idea which one I should ask for. He said he has standard ones or a bigger Dell Orto. Should I just play it safe and get a standard DT one?



  • will be a nice project


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    Took the bike apart a little bit more to store it until I can make space for it.

    I'll be working on the engine first and will hopefully take a look inside this week.

    In the mean time I just need to order a rear tyre for my new rear wheel, a power valve, a carb, and a clutch case. Still unsure of what carb to buy though. My carb boot / rubber inlet measures 35mm and says 3BN on it. Is that indicating that I must buy the smaller sized carb?


  • Global Moderator

    Took the cylinder off today. Found a piston with a smashed skirt!

    Cylinder walls don't look scored, but it could do with a rebore.

    The rings and small end bearing look in VERY good condition so I'm thinking at this point the previous owner may have put in a cheap eBay piston that perhaps wasn't the right size and caused piston slap?

    No up and down play on the conrod either so I'm sure that'll be good to use again without needing work done to it but I'll have to split the cases anyway just to grab any bits of piston lurking down there as I can still hear a small scratching sound when turning the engine.

    An overtightened kick start nut stopped me from progressing but I'll get that sorted tomorrow.

    Does this look like an aftermarket inlet as it doesn't have the hole for the oil pipe on top?


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    Managed to get the kick starter lever nut off after I got the grinder out.

    Took the clutch cover off to find a bad sight.

    Although on the plus side, the clutch plates, springs and spring retaining bolts look brand new!

    Couldn't quite work out what the broken bits were, then these black rubber bits starting appearing from no where!

    Figured out where all the bits came from once I took the clutch off...

    That was what the scratching sound was. Couldn't work out how something like that could have happened, the only thing missing was the washer that goes on the end of the rev gear but that wouldn't have cause this amount of damage. Then I noticed this.

    I removed the gear to find that the circlip behind it had been pushed a little bit too far back. This could have caused the kick start idling gear to wiggle just enough that it hit the back of the clutch basket. Not 100% sure but seems feasible.

    Also there is a hole here, but I'm not sure if it is supposed to be there.

    All organised for another day.



  • Re: TDR 125 19XX
    Hi there I was going to buy this but the guy took it off eBay.
    I have the same bike that I'm tidying at the moment.
    The standard carb is a dellorto phbh 28.
    My one was imported in 2002 and registered to the guy I bought it from, the bike has been off the road in the owners shed since 2002 so the piston was seized in the bore and the carb was full of the usual green residue, nothing a new piston and a wash in my sonic bath didn't cure.
    It is a bit different to the dt like shorter rear shock, radiator ect and not being restricted is alsayw a plus.

    Good luck

    Paul


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    Hi Paul, I did get lucky with the ad I must admit. The chap had it up for £245 on an auction and no one placed a bid! I missed it at the last minute and so messaged him offering £200 to collect and to my surprise he said yes! That's interesting that you have a 28 carb as the inlet on my engine measures around 35mm. Maybe I need to purchase another inlet if mine isn't stock.



  • @MIGHTYMAN my inlet was damaged so I thought that's ok I'll fit a dt one, the dt manifold was to small for the dellorto carb so I enlarged derestricted and flowed it with the help of my trusty pen knife and a Dremel with a flap wheel on it.


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    I'm definitely considering just getting a stock DT carb and inlet as a Dell Orto is proving too hard / pricey to source.



  • @MIGHTYMAN I found a dellorto phbh 28 for about £60 new, they use them a lot on vespas. I was thinking about using one on my 180 gilera runner fxr but I'm trying to keep it standard.
    https://www.wasp-performance.co.uk/onlineshop/prod_1875543-Carburettor-PHBH-28-BS-with-Manual-Flip-Choke-Lever.html

    I think I still have the standard jet sizes written down if you need them.



  • @tdrpaul The stock carb is better than those PHBH Carbs. They are a 28mm round slide carb. Flat slide is far superior.



  • @Calum hi Calum I agree the flat slide is a lot better carb but the dellorto phbh 28 is the standard carb for the early Italian made tdr 125.
    I have a low mileage one owner 1989 tdr and I want to keep it totally original but finding original parts isn't easy.

    Paul



  • @MIGHTYMAN or grab a mikuni tmx 32. They are common enough.


  • Global Moderator

    @Calum Would I then still need a stock DT inlet for a tmx 32? Or is there a chance my current BIG inlet would be alright?