First things first, bin off that coil. Get yourself a genuine 3RM one. https://www.fowlersparts.co.uk/parts/view/4RP8231026 I had a horrendous issue that took me months to diagnose, since it would run absolutely fine from cold-warm. But after a short while it just refused to rev. It took me literally forever to figure out, I swapped loads of bits out and considering my bike was a "fresh" rebuild I didn't think it would be the "Racing Coil" I bought. It hit me when my brother was having problems with his RD I noticed he had the same type of coil and the tuner said bin that immediately and all his problems went away! So first things first, get yourself a genuine coil. Later coils are a different part number: https://www.fowlersparts.co.uk/parts/view/3KJ8231013 So it might be that your coil isn't right for your bike/year. So just source the correct year/model coil for your bike and make sure it's a genuine one (Denso I believe makes them). Secondly, I've seen this before whereby the exhaust got full of water after a DTR was stood outside for a long period of time and this had very similar behaviour. Running rich and lacking the ability to rev/pull hard. So whip that exhaust off and give it a good clean, it was very odd and not something I had considered. Later model DTs were fitted 210 main jet, but again this all depends on your carb that you're running and whether or not you're fitting genuine Mikuni Jets. Ideally you want to be fitting the right jet for the year/ignition etc.

@dominik22 Well you're doing better than me, once I was rebuilding a TDR250, thought I'd finished and then rode to my friend's house without connecting one of the carb warmer hoses! As you can imagine the temp gauge skyrocketed, luckily it wasn't far and we were able to top it up so I could get home.

Nice one, thanks for that suggestion! I’ll give that a go. Ps. Nice name!

They are fuel overflow hoses. Attach a hose like shown on the other side and feed it underneath the bike away from any hot areas. They're designed to flow gas away from the bike and hot areas should the bike fall over and the tap not be shut off.

@eric74 Fair play for getting on and replacing the tacho drive O-ring. Looking at your pics I'd say the oil is definitely coming from where the cable joins the tacho drive so I'd order the oil seal for this (item 7): https://www.fowlersparts.co.uk/parts/4083282/dt125r-3py3-1991-999-a/tachometer-gear Looking at the 4th image you posted up, the plastic breather stub should be right behind the tacho drive about where the old O-ring you mentioned is so it looks like your breather is missing (items 14 and 15): https://www.fowlersparts.co.uk/parts/4083277/dt125r-3py3-1991-999-a/crankcase Not sure whether oil would be visibly leaking out of here if it simply wasn't fitted (you never see any oil in the clear tube IIRC) so it may be that someone had the bright idea of plugging the hole with silicone sealant or something similar. Have a poke around here but be careful, if that's what's been done it would be too easy to end up with it disappearing into the crankcase, but if you're patient with the needle nose pliers/tweezers etc. you can remove a wodge of sealant like that from the outside.

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.

@dominik22 I take it your pump is not the plunger type? https://www.youtube.com/watch?v=WwFUzgr2xnA This is how I set my pump many many years ago. I did not align the lines intentionally just to run a fraction more oil due to the porting work I was running at the time.

My servo do t seem to be getting any power it's not doing a cycle all the wires look good connections has me stopped myn is a 4 wore plug witha separate yellow wire it has me stupped

@StanKn Mine was like it when I first sussed out it was removable. It was caked in what looked like cement dust! I’m glad you got it running sweet again

First gear, back brake on. I use a half inch socket with a slide bar, apply pressure to take up the ‘slack’ then a sharp tap with a rubber mallet usually does it…

Thanks for all the info sounds absolutely perfect for me, I'll definitely buy!

@erioni123 Like Callum said, use a flywheel puller to push the crank in and separate the cases. DO NOT use a screwdriver or chisel, please!… A rubber mallet is usually enough for me…

@SpookDog Ok i will try everything ……… I will find it

@Hark_Ptooie Kinda pisses you off when your recently ‘rebored’ piston used to rattle back and forwards in the barrel, doesn’t it?! I had the same experience buying a REBORED barrel & piston. I’m very particular about who does my rebores now…

Classic, well they say nothing last forever. I'd change it at the recommend service interval, if nothing else, restores lost power. Did you see my Cagiva Raptor. Nothing wrong with that engine on the face of it. Started on the button and ran really well. Last year I decided to do the service interval. [image: sakiJee.jpg] Turned out the piston had a hairline crack in on top of the piston crown and down the gudgeon locator...ticking time bomb. I had a barrel replated, new piston/rings and the bike was utterly night and day in terms of performance. The thing absolutely flew. Then a few weeks later it was really struggling to run. I went on an overseas trip and came back when the temperature had drops some, then the engine just died. I haven't stripped it enough to figure it out yet, but at 30 PSI, prognosis is not good. I whipped the cylinder head off and the piston/bore are in good shape. My guess is the crankshaft seals have given up. The restored new power was just too much for them and they've let go. Another one for another time

@Stevie-Wonder They're ace, they'll sell you a GPX TSE250R engine which bolts straight in, and other stuff like a cone-shaped shim which fits on a DTR crankshaft under the flywheel to enable running it in a DTRe bottom end.

Oh that's cool, though my brother ran a 38mm Keihin on his 2001 DTR. Just heated up the rubber and stretched it over. https://www.youtube.com/shorts/bOGAEzTaBgI

There has to be somewhere in Europe that ships to Bosnia?