DT125R FORUM

Is the power valve correctly aligned,if it has the diamond shaped base?

Hello and welcome bud.
Like Calum said,tell us some more of the DT.

Happy new year to all.

I am collecting photos from small jobs I do on my DTR, will post them when 2025 stops kicking me like 2024 did.

Merry Christmas and a happy new year,wish you good health to all, everything else is obtainable.

@HOTSHOT-III Interesting bike that Aprilia,never seen one before.
A DT could transform into something similar,twin headlights, modified bigger tank, keep it's enduro costume.

@Calum I would grab a tig/mig and extensively repair the frame. But I am known to see hope/light in garbage stuff with a lot of time and work coming back to life.
Example. I was offered an XT500 with low km's but sea salt corrosion damage to the frame,not passing "MOT" here.Very low money,but I have no time....for now waits to the owner garage until I find time.

If the cabling is not messed up the main light runs directly from the stator, doesn't load the battery.

Maybe it's from the 3ET DT200R,has the same carb as the DT125R but uses different numbering in jets, the main is 150 but is not smaller than the 210 of the DT125R.

Motul motocool expert (yellow) and Aisin coolant for motorcycles (blue)
I prefer Motul because it's the best I tried,has the least fluctuations in the temp during usage.A little expensive 10 euros per liter.Normal riding city or cruising 65-75c temp,on the high side 87-90c when going up the mountain through steep bad fire roads.
Second one is the Aisin,similar performance, normal riding city or cruising 65-79c and up to 95c on the fire roads.5L for 21 euros.
All these on Greek hot summer evenings,34-38c.
Currently filled with Aisin because I had 3 liters left and doing some work on the bike.

https://dt125r.activeboard.com/t49963266/cdi-compatability/

It's from the old forum,hope it helps.

@Calum That's another chapter of 2stroke tuning,we talk about a "cough cough" a somewhat civilized power delivery or the 2stroke mad max madness ????
@Sid_Strummer can tell us what he want's

@Calum I know.It's my opinion that if you have to grind the PV you are at the max of what Yamaha designed.
You can overbore to max 70mm I think with the PV at it's limit,no reason for that. 74mm is the outer diameter of the sleeve if memory serves ok.
Resleeve and have all the fan from the start.

@Sid_Strummer I remember that max bore is 68mm, after that you have to grind the PV, I wouldn't do that.
Re-sleeve it to the 66mm.

@SpookDog I always keep old bearings for use at this kind of jobs.

Last time I had the bike working I did about 250km (city/open road mixed) on 100 octane,then switched to reserve.I am running a little high CR,no 95 or 98 gasoline for me.

WoW big pricey project,you have a long way ahead but it seems to be a great ride to the dream machine.
All those shinny parts!!!
3rd project build in a row!!!
I am a used parts guy....so waiting for the next "shinny" post.

@SpookDog said in Rear disc?…:

Can anysod point me in the direction of a decent rear disc at a reasonable price? I have an early 1988 ~ onwards bike and the prices I can find are hideous! I’ve seen RE discs and 2005+ ones going for better money, but are they a different fitment?

I just want a half decent stainless steel disc without wavey bells and whistles!
Please help!…

I had purchased EBC discs for DT125R some years ago from ebay,but then had the price of 45 euros and now they are at 76 euros.

That's very cool idea!!!
I was thinking to make a plastic protection for the debris at that location but you made an excellent modification.

A tyre/rim chart I have says up to 80/90-21 is ok,90/90-21 is what I will put when I change tyres.
Don't remember where but someone fitted that size to 1.60-21 rim and had no problem.

It's doable. I've taken parts from 3 Mikuni 28s.One from my DT,one of a TDR250,one that has oil feed tube don't know what bike and made my current carb.
The one with broken is off,the bent tube is overflow if memory serves.
Chokes are the same.