DT125R FORUM

Forum patched and updated. Fixed some database corruption issues which was having a knock-on effect with emojis so hopefully they're working now.

@HOTSHOT-III Hopefully the issue gets resolved as I don't want to lose the data they're hosting. The important stuff I ought to host here to guarantee it isn't lost.

Hello Welcome to the forum Yes, photo uploading is disabled as I host all of this myself and imagine hosting is expensive. Imgur was the preference, but is now blocked in the UK and therefore cannot be viewed here But yes a build thread would be awesome.

It sounds to me like the relay. So the starter motor button isn't wired directly to the starter motor as the starter motor requires a lot of current. Instead the wire is connected to the relay and the relay activates the starter. So I'd look in that general vicinity, sounds like it's starting to go faulty, which isn't bad considering it's age and the high amperage that it is subjected to.

@HannesDTX Check all the things @calum said, plus are you sure you've done a FULL carb clean? A lot of people just put them in an ultrasonic cleaner for half an hour and expect to bolt them back on. Doing this doesn't sort the blocked emulsion tube which is a leading cause of DTRs refusing to rev out beyond 6000rpm, precisely the symptoms your bike has. Do a full carb clean including the emulsion tube (the brass tube the main jet screws into). A lot of people (including bike shops) miss this and don't realise it comes out because you have to screw the main jet back in without the brass washer and tap it gently to remove it from the carb body. The space between this and the carb body gets blocked with moisture, dirt etc and blocks more and more holes in the tube (which is how the air atomises the fuel) until it just starts fourstroking and won't rev out one day as this controls the mid-throttle fuelling. Just chucking it in an ultrasonic cleaner usually isn’t enough; you have to actually remove everything from the carb body, physically make sure all the jets and air passages are clear, then reassemble. Make sure the air supply to the emulsion tube is clear as well, it's the small brass tube on the right of the carb body just in front of the carb-to-airbox rubber. You should be able to blow through it, but only just.

The 230 is up and running! I have run about two tanks through it, but the chinese pwk carb I'm using is bad (had it in a box of junk carbs), so it drinks more than it should. Its stutters and putters on low throttle openings, and nothing I've done helps the issue completely (jets, needle and even filing the cutaway on the throttle slide). Runs well on more throttle though, and pulls pretty well. I have another clone pwk on the way, and hope that will work better (had good reviews). Internal gearing is higher, so 5th on the 230 is about the same as 6th on the 125. Went from 17 to 16 on the front sprocket, and now I'm doing just abt 5k at 80kph. It goes better than my sligtly modified 170-engine. I still have stuff to do with tuning the carb when I get it, tuning the zeeltronic, fixing the starter cicuit etc. I have not figured out how to integrate a starter button close to the throttle handle yet. Not a lot of space to add a switch next to the stop switch (that I'm using as a map switch now). Engine seems fine, no problems with vibrations, shifts are good, and clutch is holding up. Some small drag from the clutch at standstill that can make it a bit hard to shift when standing still, even if the engagement point is fairly early on the travel of the lever. Using a DT LC clutch cable, because the DTR cable did not fit the engine, DT LC cable was a perfect fit. I guess that's it for this update.

Also don't forget to change bulb in light cluster for an led Kind regards