What's missing here?



  • If it's running lean or seems to be at high revs, there are five simple things to try.

    Float level, is it getting enough fuel?

    Tank cap, is the vent blocked or partially blocked cause fuel starvation?

    Fuel tap, is it opening fully and is it and it's filter clean?

    There is an inline filter in the brass pipe in the top of the carb, is it blocked?

    Air filter, is it very dirty or over oiled as too much fuel is as bad as too little?



  • All good ideas there thanks 😉

    Float level was set when I changed the needle stop as it was pissing out fuel from the carb when I got the bike, but sadly the problem was present before.

    Tank cap Is a good shout, Ill take a look at that and the filters once the fuel level gets lower.

    Air filter is new and not particularly over oiled, but again its been doing it with this one and the previous filter so can rule them out.

    Ordered a new coil, HT and cap anyway. Possible the one on the bike is 25 years old, so cant hurt 🙂



  • Should also add that the bike revs freely to the red line when in neutral with no load.



  • @Pablo13 That rules out somethings, but the real test is under load. That's where the problems will become apparent.



  • i would definitely whip the cylinder off and see whats going on for the sake of a new piston and small end and a gasket set ... probably would have been my first shout and check for wear around the ports if you have tried everything else but it does sound like a electrical or cdi issue ... 240 main is best for dtr if you are running a aftermarket exhaust but its a tad rich so i always run without a snorkle never had a problem in the rain ect ....



  • So I fitted a new coil. Its a little better but still not quite right. Gets to 9700 now before going flat, but still feels like a little step around 9 where it tails off. I checked the carb and I think someone has previously removed the filter as I cant see one in there. I've got an o-ring coming for the tap so will wait until it comes then check that out too. Then I guess its time for a compression test, but I'm not expecting anything out of the ordinary because it runs sweet everywhere else.

    How much is one of these zeeltronic jobbies then? 🤓



  • @Pablo13 Which country do you live in dude???

    You can but direct, dependent on whether or not they ship to that country;

    http://www.zeeltronic.com/page/aprilia.php

    Or off good ole ebay;

    https://www.ebay.co.uk/itm/CENTRALINA-APRILIA-RS125-1996-2011-PROGRAMMABILE-CDI-IGNITION-ZEELTRONIC-MOT-122/271194690954



  • I'm in the UK.......just see the price, lets hope it's not that 😃



  • @Pablo13 PJME sell them, I recently got one for my RS.

    I bought my DTRE Ignition from Skellerns Cheltenham years back. They ordered a bunch in and I got mine for £160.

    Failing that you could get ignitech CDI's.

    The price is still cheaper than an OEM one new from Yamaha.


  • Global Moderator

    Just to chime something else in, my TDR doesn't really have much past 9-10k either, but it seems to be due to a small hole where my silencer meets the expansion chamber. Whenever I patch it up, I get much more pull up the top of the rev range. Sadly my fixes don't last long 😪