The KTM300 Thread

Discussion in 'Thumpers' started by GasGas300, Jan 11, 2010.

  1. ChasM

    ChasM Been here awhile

    Joined:
    Nov 27, 2007
    Oddometer:
    803
    Location:
    Loomis, CA (Sacramento area)
    Not necessarily.
    When the rad reservoir is properly filled to top, coolant will automatically flow into and out of the coolant reservoir as the coolant heats up and cools down for maximum efficiency just like in cars and trucks.
  2. alvincullumyork

    alvincullumyork Ol Two Flags Supporter

    Joined:
    Feb 26, 2012
    Oddometer:
    20,108
    Location:
    The dry part of the PNW
    I'm in for another dollar!
    Foiler, Gordy and nzrian like this.
  3. backpain

    backpain Been here awhile

    Joined:
    Dec 1, 2013
    Oddometer:
    344
    Location:
    around
    I cheated last week. I kissed a girl and liked it. I tasted her blue chapstick. She also had a spider tatoo.



    She’s shy:
    B21094EC-CF5C-4C45-8FC7-0124A3457240.jpeg
    Bitingdog and alvincullumyork like this.
  4. backpain

    backpain Been here awhile

    Joined:
    Dec 1, 2013
    Oddometer:
    344
    Location:
    around
    I think I have to go back to a smaller rear and red hair to like the old girl again (there was too much shifting in my case with 13/52 and I don't know why I took out the red spring).

    Not saying that if I find a local used counterbalanced TPI 300 (of which mine has neither of the younger traits), I wouldn't take her to the cosmetic surgeon for upgrades (swap my suspension into it and try to be happy again).

    . . , but then I would want to swap the fork axle mounts (new model axle diameter) so I could swap front wheels more easily, and then the unspoken autoclutch decision (which, I suppose is akin to permanent birth control) . . . . ;)

    The old lady still looks good next to her old friends. Don't know why she’s wearing those ugly glasses (apparently left the mirrors up all day - no single track)


    16F83045-E462-4A9B-9D5A-B2BAD72287FC.jpeg
    petew and bikerjim2000 like this.
  5. RideFreak

    RideFreak Torque Junky

    Joined:
    Apr 17, 2009
    Oddometer:
    15,229
    Location:
    Out in the NM Dez somewhere
    Nice pic Rusty.
    Regarding a fan, not all of us are expert trials riders so our passing through something technical isn't necessisarily as smooth or quick as you and likely the bikes will run warmer than yours. The other thing is with a high compression head the bike runs hotter then with the stock head effectively reducing the "safe zone" between the operating temp and the boil over point. I don't leave the bike idling for any length of time but I also don't necessisarily shut it down every time the wheels stop turning, turning off the motor isn't a cure all for preventing a boilover. With a fan I don't worry about it ether way. Unless your climbing hills the fan really isn't needed in the desert and if you are climbing hills it can get hot enough to smell the CF of the pipe guard so it can easily reach 240 near the top of a run, with the right fan that info is there to see. Personally with a 2 stroke I prefer it to run cooler and the fan most definately does that. Your yardstick is that it isn't boiling over, a boil over occurs around 240~260 degrees, my fan comes on at 190 works to try and keep it there. If you've ever seen the data from back to back dyno runs on a 2 stroke, the hotter the motor gets the more the HP falls off, it's not huge but it happens and usally why they won't do more than 2 pulls in a row. @ $150 ia fan is money well spent not to expierence cooling problems which can easily run $400-$600 bucks if the headgasket decides to let go the next ride which isn't unheard of after getting the engine hot enough to puke it's coolant.
    petew, cal08, Bitingdog and 5 others like this.
  6. Gordy

    Gordy SUPPORTER

    Joined:
    Dec 30, 2001
    Oddometer:
    32,507
    Location:
    NM
    :thumb
    I’m mostly just messin with you. I’m fairly certain that a fan can help but my belief in conspiracy theories is un-stoppable. :lol2
    Why doesn’t KTM sell the bikes with one? They have to be concerned about all these bikes out there melting down, right?
    I think that a fan restricts air flow more than it creates at most speeds. Mostly slow crawling speeds could obviously use something more than “moving along”.

    I’m going to put some heat indicator tape around mine to get some real world high temps. If it’s hot, I’ll try one. See???? I’m willing to listen and (maybe) change!
    petew, Bitingdog and alvincullumyork like this.
  7. retroone

    retroone Long timer

    Joined:
    Jan 11, 2006
    Oddometer:
    2,045
    Location:
    albq NM
    My new 300 TPI fan comes on maybe once a ride if that... I average 14 mph on a good day...
    petew and Gordy like this.
  8. adv_sacrifice

    adv_sacrifice Been here awhile

    Joined:
    Aug 18, 2017
    Oddometer:
    328
    i just put one on to prevent overheating. i was riding my yz450f in the woods and it would boil over with my skill/terrain. i put a fan on and didnt have the issue again (along with some other non-cooling related bike changes/added skill). so it works for me. just being proactive in keeping the bike happy since its my first 2 stroke/woods bike
  9. Nowwhat

    Nowwhat I'll Go Second... Super Supporter

    Joined:
    Mar 2, 2007
    Oddometer:
    9,044
    Location:
    On the Ground Laughing
    I am shocked how little the fan comes on.....2020 300tpi xc....
  10. Gordy

    Gordy SUPPORTER

    Joined:
    Dec 30, 2001
    Oddometer:
    32,507
    Location:
    NM
    A 450 4T is a different animal and needs one to survive any ride.


    Ahhh.....retroone stays moving, like maybe one stop all day! :rofl
    retroone, adv_sacrifice and Nowwhat like this.
  11. RideFreak

    RideFreak Torque Junky

    Joined:
    Apr 17, 2009
    Oddometer:
    15,229
    Location:
    Out in the NM Dez somewhere
    Do you use a lower pressure cap with the catch bottle? If not anytime there's coolant transfer into the catch tank you've subjected the system to the max pressure the factory deems safe. Catching the coolant is definately a benifit but I would prefer not reach point that exceeds the pressure relief which is basically the boil over temp. I may be wrong but I thought the catch system uses the OEM rad cap.
    alvincullumyork likes this.
  12. RideFreak

    RideFreak Torque Junky

    Joined:
    Apr 17, 2009
    Oddometer:
    15,229
    Location:
    Out in the NM Dez somewhere
    I don't think KTM pritoitizes a fan over weight on the 2T, look what happened to the subframes. These days it's all about how light they can make it and of course they expect you to rebuild pretty frequently. Also like you said there's plenty of riders that don't use one, especially guys racing. If you put tape on, place it on the bottom edge of the radiator, that will give you comparable values, placing it on the cyl will be a bit higher. You ride well enough where I doubt it would be an issue.
    Bitingdog and alvincullumyork like this.
  13. guns_equal_freedom

    guns_equal_freedom Long timer

    Joined:
    Jul 1, 2007
    Oddometer:
    7,453
    For the same reasons why they don't sell them with spark arrestors or radiator guards or aluminum hand guards or....
    Bitingdog likes this.
  14. Gordy

    Gordy SUPPORTER

    Joined:
    Dec 30, 2001
    Oddometer:
    32,507
    Location:
    NM
    That's funny, I've never ran radiator guards either and haven't got around to aluminum hand guards on the new bike either. Not sure if I will, I kinda like not having them up there. My friend messed up his wrist pretty bad when he got it caught in one so I'm deliberating the pros and cons right now. My old bush whacking bike wil keep em though.

    Btw, none of the armour things mentioned could cause an engine to overheat so that's not a valid argument. If these bikes were overheating riding like they are meant to be ridden, KTM would be forced to sell them with fans, much like they do with most of their 4Ts.

    I suspect that quite a few overheating issues are 1) jetting related and 2) clutch abuse. :dunno

    I also think that a fan on a 2T is not a bad idea but not necessarily a good one either. :scratch

    Remember, it's Ready to Race, not Ready to Idle! :rofl
  15. timeOday

    timeOday Long timer

    Joined:
    Jun 20, 2008
    Oddometer:
    3,534
    Location:
    New Mexico
    Their stuff is beautiful and also effective in my experience. However I went with cheaper (DeVol) guards on my 300 because they have an additional backplate (behind the radiator) to protect against folding and which I hope will make them stronger. The bulletproof guard on my 500 bowed out a bit when I dropped it on its side on a rock and the guard took the brunt. I am not complaining, given the choice at equal cost I would probably still choose them, but I am not sure the extra cost of milling the whole guard from a block results in additional strength.

    Now that I think about it, mounting a radiator fan with the Devol guards is going to be difficult because they cover the back of the radiator too.
    petew likes this.
  16. IanInCalgary

    IanInCalgary Been here awhile

    Joined:
    Nov 22, 2011
    Oddometer:
    292
    Will a "standard" sealed chain such as a DID VX2 fit on the '19+ bikes? The stock chain is narrower than typical so that its dimensions are close to a non-sealed (old-style) chain.

    Ian
  17. N8

    N8 I prefer my pumpkin with a blue & white mask. Supporter

    Joined:
    Dec 27, 2012
    Oddometer:
    6,702
    Location:
    Lancaster, PA
    Yes, but my experience with the non-VT2 chains is excessive masterlink clip & pin wear.
    IanInCalgary likes this.
  18. Bitingdog

    Bitingdog That's not my dog

    Joined:
    Apr 2, 2015
    Oddometer:
    17,301
    Location:
    The bad side of the PNW
    I've never overheated my 300 when riding desert and flowing trails in 100°F+ heat.
    On the other hand, I have boiled over in tight and technical slow terrain, muddy hillclimbs, and situations where plenty of crawling & clutch slipping is necessary; even at below 32°F.

    I don't have a fan, but I need one sometimes photo0.jpeg 20190322_153321.jpg
    petew, Anatoli, Dan950ser and 4 others like this.
  19. ChasM

    ChasM Been here awhile

    Joined:
    Nov 27, 2007
    Oddometer:
    803
    Location:
    Loomis, CA (Sacramento area)
    The OEM rad cap is perfectly fine although I prefer the Tusk 2.0 thermo cap. I have successfully used the Tusk rad cap on two previous KTM's and my current Beta.
    alvincullumyork likes this.
  20. Nowwhat

    Nowwhat I'll Go Second... Super Supporter

    Joined:
    Mar 2, 2007
    Oddometer:
    9,044
    Location:
    On the Ground Laughing
    Just buy a 2020 tpi.... they run cooler...... think of all the money you will save on a fan....
    Bitingdog and alvincullumyork like this.