gary09

Thanks for all the ideas guys, I have found the problem. On removing the flywheel/ generator cover about 1/2 a cup of water came out! The various coils and the pulser coil were dripping. All now wsshed out with wd40 then dried. Now she is flying again.

Anybody help please. I have a 1990 DTMX 125 and live in France. It is the old air cooled 6 volt electrics type manufactured mainly in the 70's. It is a 1990 as they were re introduced but with electronic ignition in France for a couple of years. The bike has symptoms almost like dirt in the carb. It revs freely and will hit the red line in 6th on the flat or with a tail wind. Starting is no problem. However into a headwind or a climb on full throttle but mid range revs it misses subtly and lacks power. Almost losing half it power. I have stripped and cleaned the carb several times. Checked adequate flow from the fuel tap, tried another plug and plug cap and another ignition coil. When it has this power loss you can drop a couple of gears and it will happily redline but bog down again jerking and feeling like fuel starvation even at 5-6 thousand revs as soon as you get into 5th or 6th in the 'load situation'. I have also tried moving the needle up and down by two notches on the carb piston but again no effect. Any help woukd be appreciated I love this old bike but it is driving me nuts!

You got it, red frame and square indicators, black tank with decals, I'll try and post a pic after I've written this but haven't tried before so I don't know whether I'll succeed.... Thanks for the info, much appreciated.

I had a very courteous reply from Yamaha who have informed me that it is a 1989 model, manufactured in Feb 1990 and was registered in april 1991. Seems it must be one of the very last air cooled jobs?

Thank you DirtyDT, at least I know what tech manual to try and get now!

Hi guys, I live in France and have juust bought an air cooled DT125 which has a first registartion date of 1991. Frame number is 2A8186892. Everything I search for with that year is water cooled, can anyone please assst with what year the air cooled models stopped and what year colour scheme this is? It has a red frame and black tank if that helps. Thanks for any help.