ChitownRC

By now you all may well now that Traxxas company will soon bring to mark if they havent already a 33% nitro fuel that they claim has 10% more nitro content than standard nitro fuels ( last time i checked 33% minus 30% was 3% but whatever.)

They claim this fuel can be used in the 2.5 and 2.5R motor to exstract even more power..... Heres my problem... Why is traxxas advertising this? I feel that the trx 2.5 and 2.5R are both already jucied to the absoult max of there capability. I feel that these lil motors are taxed out, And then traxxas dumps them into the hand of novice nitro rc'ers which do not fully grasp the ability to tune such a tighty wound powerplant. Then when they do use there rc model and run it just slightly out of tune and use an even hotter burning fuel the motor is no better than a paper weight. I have been personally invoved with trying to tune two of these motors ,with out any luck whatsoever, and id like to concider myself rather savy when it comes to nitro rc. Niether of these motors made it past the 1/2 gallon mark!! Every possible precaution was taken during break in and running off these motors but that just doesnt seem to matter.

After one season of club racing i have learned that if you try to warrenty you trx 2.5 race motor with traxxas and you tell them that you used there motor for racing the warrenty is void! Even if you use traxxas top fuel. I have also learned that traxxas feels that 12 to 14 hrs of run time is all that can be expected from these mills. (thats around 50 to 60 runs)

Also, One of my buddies is the mechanic (term used loosely) at the local hobby town and he sees Tons of fryed 2.5s a month. He is constenly replacing motors in t maxx's. (too much load on a small block)

I know there will be a ton of guys preaching the greatness of the 2.5 (it was rcca's voters pick for best motor) and i thats fine. I just dont think traxxas should be trying to squeeze these babies for anything else. But thats just my opinion....Hows that go...... opinions are like a**holes Every bodies got one and they usally stink. Im sure many will think that of this post but maybe it will give us somthing to debate.

I know that my 2.5 is probably a fluke. I bought the Maxx used, and have put about 4 gallons through it myself. This was my first Nitro vehicle, and I made many mistakes (temps in the 300's) while learning how to tune it.

Untill about 2 months ago, I was running the Stock Maxx pipe on the 2.5. At that time, I switched to a RD Logics curved pipe, Which brought new life to my Maxx. I have never run Top Fuel in my Maxx, I've used Monster Horsepower from Trinity, which only has 12% oil content.

As for the large number of 2.5 engines your friend sees that are destroyed, how many of them are being run by inexperienced tuners, who may be diagnosing the conditions wrong? Many times, I've wondered if a bog I noticed was caused by too lean or too rich, only to get lost in the needle settings trying to get it to run right. Engines are a "luck of the draw". Out of 100 engines of any make, there may be 99 GREAT, but that 1 bad one is usually the one you hear about..... Just my opinion...

Every motor that he replaces is opened up before they tell the cust he needs a new one. He just doesnt go on the customers word that its blown. Im sure you motor wasnt a fluke, i i think you opinion is probaly right , but id bet its more like 1 out of 20

Quote:Every motor that he replaces is opened up before they tell the cust he needs a new one.

I didn't mean to imply that your friend was ripping anyone off, sorry if it seemed that way.

On the Traxxas 2.5, I'd say maybe 1 out of 20 are good, maybe a little more, maybe less. I exagerated the 1 out of 100 comment, to make a point, about all engines across the board, not just the Traxxas engine. Example being, a lot of people in our group run, or have ran at some time, the Sirio .18 in their Maxx's. Of all the people that have run the Sirio, I think only two have had problems with them. Not saying their tuning is any worse than anyone elses, they might have gotten a bad seed. This is less common in the top end motors, since they are precision machined, but they are assembled by hand. A little too tight on this screw, there goes an O-ring. A little too loose here, air leak or even worse, point of entry for dirt.

trx 2.5 is decent motor. I have tuned a couple and now I will be tuning up my freinds 2.5r. I feel confident that it all comes down to break in and proper running of the motor therafter. yes it is a powerful lil mill that can be a little finicky in the hands of the inexperienced, but with proper know-how it can produce many gallons of fun and exitement. They released 33% for the 2.5's simply cause they become more efficient power producers and actually run cooler than with 20%. Pretty smart from a company that has had a bad rep from bad tuners saying that they burned out their motors in a 1/2 gallon or so. This new fuel should give great power and cooler temps out of almost any motor.

rocco79 Wrote:( last time i checked 33% minus 30% was 3% but whatever.)

10% of 30 is 3

3+30=33

Crazy math! :confused:

you think 2.5's are bad, I guess you never saw mine in the revo. I used to hate the 2.5 in the maxx but i learned from that engine how to better tune an engine. Now about 3 engines later i think i have become rather good at tunning. My 2.5 now runs around 250 and has balls of power. My sirio is another one that has its ups and down. Im on my second sirio and i can get this one to tune. Maybe its still breaking in but right now i cant get a decent tune outa it. My previous sirio tuned like a champ but i think the one i got now is probly a bad seed. I would say 99% of engine problems are related to tunning. And i can say that because i have tuned a lot of peoples engines that are just starting off. And the idea of 33% fuel is awesome. It will run the engines cooler, give some more power, and hopefully make a lot of people happy. I already have 3 gallons ordered so i hope they come in stock soon like they should.

R/C Madman Wrote:10% of 30 is 3

3+30=33

Crazy math! :confused:

I just thought a fuel with 10% more nitro content than a 30% fuel would be called 40%. Maybe im thinking about it wrong

[QUOTE=thenewguy821]I didn't mean to imply that your friend was ripping anyone off, sorry if it seemed that way.

I in no way thought thats what you meant either bud. Were just talking here,i was just trying to get a good thread going

My opinion is that 1 out of 20 2.5's is BAD meaning 19 are good. They are precision racing mills and take precise tuning skills to run good.

Some engines have a broader "good tune" range than others. The 2.5 is picky in that aspect.

Tuning an engine is all about "reading" how the truck is running and knowing what you need to do to fix it. that may have not made sence but o'well

A good example of what Tex is saying about reading your truck, the Traxxas manual says run the 2.5 no higher than 270*, and that's pushing the high side. My 2.5 ran the best in the 280* range, before the addition of the RD Logics pipe. Good smoke, both on low and high RPM's, good bottom end torque, and good high speed. If I "Tuned to temperature", the truck would bog, spit fuel, and was near impossible to keep running. I'm not suggesting that all engines should be tuned by watching the smoke, just that is how MY 2.5 wanted to run...

My 2.5 ran pretty good for 5 gallons. I was happy with it.

rocco79 Wrote:I just thought a fuel with 10% more nitro content than a 30% fuel would be called 40%. Maybe im thinking about it wrong

10% of 100 is 10

40% has 33% more

Again Crazy Math! :confused: