I bought my X one year ago, and raced it the whole 04 season (desert) without fault, all stock, just aftermarket tires and UNI filter. Now, for 05 I installed a Digatron as my first "mod" just to be shure I was running optimum (~1250F) an all ranges (pilot, neddle and main jet).
I run it two days ago and found that my initial temp (with stock jetting, neddle in 5th slot) at idle was 900F, good, but then, 1/4 to 3/4 throttle, the temp goes up to 1400 and beyond REAL FAST. Even cruising at half throttle I read ~1400F. Full throttle goes +1500. Now I am afraid of a piston seizure and cant ride it with confort as before. I did a plug check, and they were preety clean, as new ones.
Is the Bomb supposed to run this high temps? Last year I sustained full throttle for 6 - 10 minute period without a problem!!!, but I did not know it was running THAT hot.

I've alreadly ordered 170 and 175 main jet, but what can I do for the neddle? (already in 5th slot). This is on stock machine, with stock exhaust, and no air leaks (I sprayed a flamable solution around carb boot and no idle change happened).

Thanks

 

How close did you put the bung to the head? A friend had issues being to close and having to high of readings.

 

Wouldn't closest to the head be the most accurate reading. Afterall that is the temperature of the exhaust gas as it leaves the cylinder. Placing the bung downstream would allow the gases to cool somewhat.

 

If you are to close there is flame that gets to the sensor. On the Vforce the flame goes four inches into the header. this info is coming from FST (mickey dunlap) the optimal place is six inches from the head. Most of the sensors recommend this distance in their literature.

 

don't worry so much about the needle position until your main jet is right. Once the main is ok, you can then set the needle.

Bumping up the jet size effectively changes the needle position since more fuel will be flowing by the needle in the mid as well as top end.

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D Slider 1,500+ is in the very ugly field. I'm very suprised that it did not go bang with that high of sustained temps.
Follow ds650ratrider advice, get the main jet right.

 

I placed the probe at 5in, since some recommended 4, and others 6, I placed it in between. Jets should arrive soon and hopefully I'll see a lower temp. I see (read) many of you are glowing the headers, might have the same problem. I am surprised that a new "stock" machine could be set soo lean at the factory.

Max power is supposed to be achieved at around 1250F, am I correct?

Thanks

 

when ever i have been on the dyno we were much more worried about the air/fuel mixtures more than the exhaust temps. if you talk to serious engine guys some say air/fuel some say both? but i have yet to melt down a motor that was tuned to have correct air/fuel mixtures. we ran a 1500hp drag motor and had a air/fuel computor on board and after every run we would check it to see what the reading were and adjust. at the end of the season we torn down the motor and found no heat issues at all sense we kept the air/fuel correct. my 2 cents

 

I had the same experiance as Jeffroe.
If you want to know what the A/F is doing you need to get an A/F guage, not a pyro. I pyro will show hot when you have the timing late. A pyro will show hot when the outside air temps are hot. A pyro will point you in the wrong dirrection sometimes. A pyro is like a ruler and a A/F guage is like a micrometer.
If you want A/F right on the money, buy the guage, mount it, tune it, take it off and your done until the next mod.