TRX25R break-in on a stand?

[ByPS]

Hallo nitro engines gurus,
I have one question abou breaking of new engine.
I am awaiting for new engine which i plan for racing and old one I will have for bashing and practice.

Now my questions is: did somebody try to break in on a stand for two fuel tanks and after tese two tanks go to ground and finalzie breaking?
I know, in owners manual on page 28 is traxxas giving info about poor results with breaking on a stand.

But a lot of nitro guys are breaking with this stand method and engines goes very good. I can not to decide which method and why I have to take.
Which way is better for my engine?

Thanks a lot and excuse my english.
Petr.

 

[jetmechG550]

For the 2.5R it is highly recommended not to break in on the stand. That came for the Traxxas engineers and tech people. I forgot the reason why exactly but they did have a really good one. I did the recommended procedure on my Revo and so far the engine is holding up well with good compression and the piston looks in good shape. I've got a gallon or so through it. If you do choose the stand method and you go to do the engine replacement program through Traxxas don't let them know, they may not honor it since you didn't break it in as they want you to. HTH

 

[ByPS]

I undesrand. T know the reason why not can be very itneresting. I can not found any reason, only infor from manual: "poor results".
Everybody here broke engine with out iddling on a stand?

 

[Savage49]

Here is where the problem is, If you let your engine just sit there and idle rich, you are not allowing the engine to first get above 190 on the piston and sleeve assembly, that temp is where your Block and Sleeve start to expand, if you just allow it to sit there and idle your basicly just beating up the pinch giving you a shorter engine life, True you are pushing alot of oil thru the engine, but just beating away at that pinch. Also if you talk to the pro's that do that method they usualy pinch the engine after about the first gallon to regain the pinch and have it set. Now alot of engine manufacturers want you to first get the engine up to temp fast and heat it up to 200 and then shutting it off and allowing it to cool. The process is like hardening of tool metal, you heat it up and cool it off giving it extra strength, called heat cycleing. I have never had a bit of luck just sitting on a stand and allowing it to idle thru a tank, i always lose the pinch about my second gallon of fuel, with heat cycleing i have gotten as much as 4 gallons on my engines, and trust me i am abusive to my engines.

 

[Plaidfish]

Here is where the problem is, If you let your engine just sit there and idle rich, you are not allowing the engine to first get above 190 on the piston and sleeve assembly, that temp is where your Block and Sleeve start to expand, if you just allow it to sit there and idle your basicly just beating up the pinch giving you a shorter engine life, True you are pushing alot of oil thru the engine, but just beating away at that pinch. Also if you talk to the pro's that do that method they usualy pinch the engine after about the first gallon to regain the pinch and have it set. Now alot of engine manufacturers want you to first get the engine up to temp fast and heat it up to 200 and then shutting it off and allowing it to cool. The process is like hardening of tool metal, you heat it up and cool it off giving it extra strength, called heat cycleing. I have never had a bit of luck just sitting on a stand and allowing it to idle thru a tank, i always lose the pinch about my second gallon of fuel, with heat cycleing i have gotten as much as 4 gallons on my engines, and trust me i am abusive to my engines.

I have to say some stuff about this one...No offense meant... First iif you use the stand I think he is reffering to, it's one where you take the engine out of the RC and mount a propellor to it....this creates the load...next you don't idle the engine...as you stated before that does nothing bu tbeat the crap ou tof hte sleeve.....you actually run the engine at WOT but you richen the hell out of it so the temps are stable at around 210 and then heat cycle them for about 6 tanks letting the temps get a little higher every 2 tanks up to 230.....I've had my last 3 mills done like this and what a difference....I don't get that much more life out of it...maybe 2-3 gallons but I definatley get more time from the pinch staying longer.......and if you are only getting 4 gallons before it's done you need to richen you engine up a lil....I get more than that from my RG and that's supposed to be the one of crappiest mills on the market......

 

[Savage49]

I get what you are saying on the stand method, Around here there are quite a few guys that think you should let the engine sit on a stand rich as possable and let it idle two tanks thru the engine. The method you say is very good way of doing it. As far as my engines and keeping them running right at 240 for my TRX, they get a nice smoke trail. The first TRX i had only lasted 4 gallons, it had a hard life before i got it, one busted high side needle, o-ring went out on fuel tank, Carb came out twice i can remember. I just bought a brand new 2.5 today, we will see how much i realy get out of it now.

Dave

 

[Plaidfish]

oh I forgot you were talking bout the 2.5 mill...yeah 4 gallons is good for them....sorry.... My 2.5s liked to run around 260 but they would last like 2 gallons and I'd give them away to people wanting to grenade a mill....


and then sell them on E-bay to some kid's dad to give it to his son for his christmas present.....

 

[ByPS]

So, OK, finished, my new TXR2.5R engine successfuly broked in.
Let see some litle video which shows a lot of power. Car is very dificlut to control. Half throttle makes wheelies. Temperature was aroud 220 F. It makes wheelies on road too.
With out body engine goes around 176 F.
http://www.pitbullseden.cz/ByPS/Video.asp
Last four links.

I thing that MIP clutch shoes and SportTrax wheels hleps very much. Clutch is 14T and spur 40T. Car have setup from traxxas pages: Basic racing setup.