DT125R FORUM

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.

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.

@Julius And what type of CDI unit do you have?

But what you're talking about is replacing the whole ignition system, flywheel, pick up, stator and CDI because you don't want to have your RE/X crank rebuilt. Which PJME do for £40 https://www.pjme.co.uk/acatalog/Yamaha-DT125R-DT125-R-Crank-Rebuild-4121.html#SID=1170 That doesn't make any sense

@Challenger [image: error] Hi, I followed the advice of Spookdog and Stevie Wonder and ordered one in Portugal from Romeu.. is now on its way and can arrive at any moment in terms of price this was also the best option. I'm very curious about the sound and performance.

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.

Make sure that the air waves are cleared on your bike, you don't seemed to have mentioned this. So there is nothing nasty blocking your intake solution. A quick, dirty, way to confirm this is to just remove the airbox to carb joiner and take it for a quick run. Sounds like it's running rich, so doing this should cause the bike to lean out. If it's only for a short time it shouldn't hurt. You just want to know if it's getting air. So check the airbox and renew the filter if you find that removing the boot fixes the issue. The other common problem is water getting into the exhaust expansion chamber. So cleaning the exhaust is really vital for a two stroke. I've seen this before where a bike was sat for a long time and the exhaust was full of fluid. The bike would refuse to run if this was the case.

That’s absolutely fine, never had a chain cover to begin with. Thanks

@GiannisT No worries The XT springs/15W oil mod stiffens up the front end quite a bit, to make my YSS shock match the forks I had to up the preload 16mm over the supplied setting and run the rebound on position 29 out of 30. If I'm honest it made the suspension a bit too stiff for off-road (I weigh 145lbs), if I'd had more time I would have experimented with cutting 10mm at a time off the DTR spring spacers to get it just right. I had Michelin Trackers (road legal MX tyres) fitted all the time I ran this setup so can't comment on street use but it's a pretty easy mod to try and it sounds like you're looking for a stiffer front end, XT springs come up for sale quite a lot because a lot of owners upgrade them (too soft for the 160kg+ XT = a good match for the DTR). Would be interested to hear if it's good for Supermoto, plus if you still want to go the USD route it won't have cost you much to try it!

@HOTSHOT-III [image: guttin11.jpg] https://dt125r.co.uk/topic/20/yamaha-dt125re-x-stock-exhaust-pipe

@HOTSHOT-III Cheers buddy yes that's the thing - the box is in good nick, I just ripped the lock tab off. I could try and make something up, but it'd be a shame as the bike's currently all original/unrestored. Thanks again! Shaun.

It's probably fine. I'd just do a compression test make sure it's within tolerance and schedule in a top end refresh if you don't know when it was last done. Generally though, the DTR is a pretty strong engine so it's damn reliable.

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

Great, thanks! The Dominator looked terriffic though.

Quick answer since I have a 2002 as well (DE03): 1 - Swap expansion chamber (the blobby exhaust bit) to an Athena or something. This was the big thing. 2 - Pull out the reed switch from behind the speedometer. Do not disconnect it or cut any wires, just wrap it in tape and stuff it aside. It detects when the needle gets to ca 80 km/h and cuts ignition there. That should be it, your bike should now rev freely to 9500 rpm and do 120+ km/h. Also: ensure that the YPVS is working as it should. Remove the round cap on the left side and turn on ignition. It should rotate back and forth a little, then settle such that the groove on top is right over the hole. Explanation on that last bit: The YPVS switches the port timing between low revs (more torque) and high revs (more power) as the revs increase and decrease. Variable valve timing, you could say. When you turn on the ignition it rotates back and forth (flips between low and high mode) to scrape off soot. The resting position should be over the hole because they used that hole to fixate the valve in low-revs mode (and turning off or removing the solenoid actuating it) when they restricted bikes, but I believe they stopped using that method after 1998 or something. If it does not rotate back and forth with an audible "bzzt-bzzt" when ignition turns on, your YPVS is not working and stuck in either of the modes. As for the inlet manifold I did a thorough CFD analysis and found that you cannot improve it. Leave the plastic bottle on, it smoothens out the gas flow. The carburetor should not need anything either, it is likely a Mikuni TM28SS with a 240 µm main jet, which is perfect.