TDR starting problem



  • So my TDR use to start on the button all the time every time, so this morning whent to start it and nothing, it was like there was no fuel getting in, after about 15 mins and fiddling with the fuel tap it's started, when warm it starts with no problem, just when it's cold, so whent for A good thrash and nearly had the temp gauge in the red? Never had it above half way before, checked coolant and all fine and so is pump, any one any ideas? Cheers



  • @rolz82 fuel tap blocked causing restricted fuel flow making it lean?



  • @declan , I thought same pal it an import been stood 3 years, so could be, but had fresh fuel in it for over 2 weeks now and never had a problem till today



  • @rolz82 If its been standing for 3 years who knows how long the fuel in it before was there for. Your filter inside the fuel tap could still be all gunked up preventing good flow. I'd look into it just to be safe, should be a 15 minute job.



  • @minia just had the tap off was a bit gunked up but not enough to stop propper flow, going to try a new plug and battery



  • This post is deleted!


  • @rolz82 but why would a plug and battery cause it is it to run hot?



  • @rolz82 I’d recommend focusing on the fueling aspect since this can cause hard starting and a lean/ hot situation



  • @declan was just thinking about the starting problem, I put the overheating problem down to just riding it hard, just been owt on it and it seems fine temp wise


  • Administrator

    @rolz82 Never had an overheating problem from hard riding on my DT. And thats modified.

    I'd agree and say look at fueling.

    Or look at the themostat.They're prone to failure after so many years.

    Always best just to renew the filters, hoses and clean the carb for good measure if the bike has stood still.

    If I store the bike, I tend to let the bike tick over with the fuel off to just take up the last dregs.



  • Been out again can't for the life of me get the temp gauge into the red now ? So tomorrow I'm gunna take the rad off and flush it top up with new coolant, as for the starting problem, it starts now every time with a bit of choke, still not satisfied so will be stripping it down to investigate further


  • DTR Member

    I struggle to get my Dt up to temp right now, let alone overheat haha
    They cool extremely well for a single rad two stroke, should never get hot really, but I have heard the standard exhausts make them run hotter.
    I've got a temp gauge radiator cap and today in 11 degrees sunshine I never got it over 60 degrees riding at 60-70mph constantly. Ragging it none stop accelerating and slowing on a backroad I got it up to 80 degrees.


  • DTR Member

    Personally my DT ran at a steady 57° C in 20+°.
    Don't believe it will run that much hotter with the Athena. Cooler if any since it's plated.


  • DTR Member

    @irongamer727 you want it hotter than that, do you have the rad scoops?
    Closer to boiling point the better an engine will run, my Dt runs like shit until 60 odd, feels absolutely brilliant up at 80 odd though.


  • DTR Member

    Rad scoops?


  • DTR Member

    It's not like the engine is 57°. The coolant is.


  • DTR Member

    @irongamer727 yes, the coolant should run around 80-100 degrees optimal. Also rad scoops as in the plastic sheild infront of the radiator. My Dt wouldn't go over 40 degrees without it.


  • DTR Member

    @glynn123 ehm well, I have that mounted yes. Would be a terrible cooling system if it were to boil at operating temperature. Sounds like your jetting is off.


  • DTR Member

    @irongamer727 no, it won't boil until well past 120 degrees with proper coolant, especially not in a pressurised system.
    For the engine to be running optimal it needs to be close to boiling point, under 70 degrees is low, cars sit at 90-100 degrees all day, so why shouldn't a bike?
    As for my jetting it's been plug chopped and is on the slight rich side, but not by much.


  • Administrator

    @glynn123 90% of cars are not performance tuned, not sure where you got that information but pretty sure that's incorrect. You don't want your engine to run that hot, or rather the coolant. And you don't want an engine to run at sub 50 degrees. But 100 sounds too high, and 50 too low. The hotter an engine, the greater the risk of detonation.

    As for performance, the hotter the engine, the more heat you'll add to the combustable mix. Vaporising fuel before it has a chance to ignite and increasing the pressure of air in the inlet tract (reducing the amount of available oxygen molecules).

    Therefore, the hotter an engine, the worse it'll perform.

    The only reason you don't want to run an engine at low temperatures is due to the fact of thermal coexpansions of differing materials.

    The opposite is infact true. Provided you can ignite the mixture (I.E. there is enough heat), the cooler an engine can run, the more performant it'll be.

    Why? Facts.

    The cooler the operating temperature of an engine, the tighter the tolerances can be. If that's true, then you can run the piston closer to the deck, and raise the compression without the risk of preignition.

    If that's true, you can obtain a better burn of the combustible mix, ensuring increased power.

    However, to add to the point that if the engine is really good at cooling, then the "Energy" of the system, heat produced by igniting the mixture, will be absorbed through the cooling system rather than being used to drive the piston.

    With that said, I guess there is logic to what you said.

    I think there is a middle ground, I don't think the hotter the engine the more performant, hence why we don't see a lot of high performance air cooled engines. But similarly, cooling the engine can have adverse effects.


 

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