Hi all, I've registered today as my son has a fault with his 2004 dt125r . He's had it a few months and all was well, then after riding home one night without any problems he parked it in the garage. Next morning it would not start. I checked the plug which was not wet and has very good spark. Checked compression and also good. I removed the fuel pipe and indeed petrol is flowing from the tank. So I thought blocked carb, so I removed this and gave it a good clean and blow through the jets etc. Float and needle all working then put back together and tried again. Still won't start. Took plug out again and this is still dry so I'm at a loss as to what's going on. Has anyone encountered this or know what's going on? Any advice is greatly received
hm well try putting some fuel on the plug then kick it over see if she fires up, maybe the chokes broken or the reeds? other than that its probably electrical
I know this is going to sound stupid, but my mate once spent a full day trying to fix his bike and then noticed that his "kill switch" was turned on so just make sure it is off (red switch on handle bars)! Like I said sounds stupid but is easy to miss. Also I would go change the plug, I once had a little blata mini motor and it just would no start I did eveything you have said and had no luck then changed the plug and it fired straight up, if I remeber correctly the dt uses the "BR8ES" plug which is NGK but double check before going to buy one they are only about £3.00!
Hope you get it fixed soon as I know it is **** without a bike.
Thanks for the replies. I forgot to say that this bike only has the electric start. I checked the kill switch and this is ok. But I guess if it was at fault it would cut the spark, whereas my problem seems to be fuel. I guess I will pull the carb off again. I did try dribbling some neat fuel into the chamber when the plug was out then tried it to see if it would fire as this has worked on cars I've had but still got nothing. It must be something simple but I'm pulling my hair out
like CooS said spark plug is best bet, i fry them every few months running premix, they can look like they give a good spark out of the engine but when you put them in they don't work well under compression and it can get really hard/impossible to start - embarrasingly i once stripped half the bike down looking for a fault but it was just the spark plug :S (hadn't owned a twostroke in a long time). also maybe check the reeds and perhaps any blockages in the exhaust. if you have access to a air line i'd also strip the carb and give all the venturi a blow through, this is worth doing anyway, its amazing how much rubbish can build up in a carb out of sight. maybe check the airfilter/air box, not saying it is but if the filter is old enough they can perish and collapse blocking the inlet. just keep working your way through and check that everything is correct and you'll come across the problem eventually
Its either the carb or the spark plug maybe the ceramic instulation has cracked on the plug, have you dismanteld the carb float and clean the fuel level jet?
Invest in some carb cleaner and some compressed air
But as fuggie said as it might just be as simple as a new plug
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Bloody kids!!! Sorry guys i'm on the wrong track! After finally catching up with my son i now have the full story. It turns out that when out on his last ride, doing about 70mph on the dual carriageway the bike suddenly started to lose power then died! Not sure why. but as i said in previous posts, compression and spark are good and carb has been cleaned . . any more thoughts as to what may have happened?
Not saying it is this but the same happened to me on my Scooter, was going along it just cut out & died. Tried everything with no luck, then ended up taking it to local garage & turned out it needed a new full top end! It had heat seized and messed my barrel & piston up :(
Not saying this is the problem for you but it is a possibility.
Cost me about £100 for the labour & parts so was cheap.
thanks, i will have to check the compression again and see. I'm quite handy with tools so if its that then i'll have a go myself. Any tips on doing the job appreciated though
how much compression are you getting? with a partially melted piston i got a reading of about 70 (psi i imagine, can't remember what my gauge is in) and 120-160ish on decent top ends, the the 70 was enough to bump it and run very haggard lol wouldn't start on the kicker
