TDR 125 19XX

[Mightyman]

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.

[tdrpaul]

@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.

[Mightyman]

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

[tdrpaul]

@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.

[Calum]

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

[tdrpaul]

@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

[Calum]

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

[Mightyman]

@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?

[tdrpaul]

@MIGHTYMAN the manifold in the pic is the standard manifold for the dellorto carb which has the oil pipe connection on the carb.

[Calum]

@MIGHTYMAN Stock carb is 28mm TMX 32 is 32MM. So it should fit,.

[Mightyman]

Now it's (hopefully) going to be warming up outside a bit, I thought I would get back into this project again. Last night took a look at the crankshaft to find some of the bits of piston had been lodged inside the gaps in the conrod..

https://youtu.be/oJv-wv8eEYQ

Also started the clean up job on the engine cases.

A bag full of steel wire rotary bits

Starting it off

https://youtu.be/9bUSrAkcnSs

15 mins = 1 down!

[Calum]

Looks like that crank is going to want a rebuild.

I don't know how easy it is to get ahold of a new crank pin for these engines. If that crank pin is scored then you may find yourself needing to buy a new crank.

[Mightyman]

The crank pink should have been sheilded by the bearing I would have thought? I wasn't going to rebuild the bottom end as it all turned over very smoothly but luckily I decided to pull it all apart in the end!

[Calum]

What bearing lol. It's a roll cage bearing so it's completely exposed.

If the big end bearing has got bits of piston in it then consider it thrashed.

For the cost of 40 quid. I would rebuild the crank. Otherwise it will fail and cost you an engine.

[Mightyman]

Don't worry it was going to all be rebuilt the second I opened the cases!