heat cycle question

[blasterboy32]

So I just did the first heat cycle on my fresh top end. Its about 85 degrees out and I used my temp gun but where on the motor should I have pointed it and I think I remember its supposed to get to about 200 degrees. Mine got to about 185-190 and then didn't go up any more. Is that bad that it didn't go up higher? Filet it run for about 3 mins at 185 to see if it would get hotter and it didn't so I shut it off.

 

[mjgnslngr]

That's about right. I think KORs vid says between 180-210 is where you wanna be.

 

[blasterboy32]

Ya. His video said around 200 is operating temp but I just wanted to make sure I shouldn't have waited longer or anything and make sure its okay that it didn't get that hot

 

[sporty982000]

I'm not really understanding the whole heat cycle.

I've not heard of it before.

I have always broken engines in. by riding normal, just not hitting the throttle hard or over revving and pushing the motor hard.No wide open running and if you ,do so, just for a few seconds.

Then after 10 to 20 hours, I do a oil change.

Is the reason for the heat cycle's to ensure due to it being bored out or a big bore kit. to ensure its not getting to hot or running lean ?

The worst thing you can do with a rebuild, it let it sit and idle for long. The rings will not break in or seal right. FYI tip.

 

[mjgnslngr]

The heat cycling is more like a Controlled break in. When you break it in the other way, the throttling isn't really consistent. Cycling takes out most of the 'riding' break in variables. At least that's My understanding.

I think that 185 number is good, not too hot, not too cool, sounds good to me.

 

[blasterboy32]

During a heat cycle you don't let it idle at all. The Rome should always be kept up and I think its no long wide open throttle until 3rd tank of gas. Is that right?

I'm Suppost to do 3 heat cycles correct? And does it matter how long I leave in between them? I know it has to cool but could I do 2 today and one tomorrow and be okay?

Also where on the motor should I be checking the temp?

 

[mjgnslngr]

I'd watch Kens vid again, it answers a lot of those questions in detail.

 

[sporty982000]

My understanding is, you want variable for a engine break in.

I have only seen breaking in a engine, by heat cycling is with a nicro r/c engines, mostly cuz they do not have piston rings. And you can damage it, due to heat. they have really tight tolerances. But Im not understanding where the simularity would be between the two.

The only thing that can come into my mind, is trying to limit, the loss of metal / shavings during a break n period. But evently you will loose the same amount of meterial just over a longer period of times.during the break n faze.

The metal comes from the rings sealing on the cylinder wall. essentially, the honing job, that criss cross / htch, all that will be gone and nice and smooth, when the break n is complete.

Rings can seat in 10 minutes or in 1 to 2 hours. I have seen some take longer.

Gap and tolerances come into play there, as to why I have seen different time frames.

So, how I have known when they are sealing or starting to seal, is usually ou have some smoke coming out the exhaust, until the rings seat.

Sporty

 

[sporty982000]

Can someone, share this video link, id like to watch it, please and thank you.

Sporty

 

[slickerthanyou]

Ya. His video said around 200 is operating temp but I just wanted to make sure I shouldn't have waited longer or anything and make sure its okay that it didn't get that hot

I think anywhere between 4-7 minutes is plenty depending on outside temp.

During a heat cycle you don't let it idle at all. The Rome should always be kept up and I think its no long wide open throttle until 3rd tank of gas. Is that right?

I'm Suppost to do 3 heat cycles correct? And does it matter how long I leave in between them? I know it has to cool but could I do 2 today and one tomorrow and be okay?

Also where on the motor should I be checking the temp?

Really varies on who you talk to- some of us do between 2-5 heat cycles, then ride it normal or easy for first tank of gas. Some don't wait for that first tank. Some do riding heat cycles, some don't do any! 8-|

Oh ya I check my temp on top of the head between the fins by the plug base.

 

[blasterboy32]

It was in a thread on here. I'm trying to find it.

 

[slickerthanyou]

Can someone, share this video link, id like to watch it, please and thank you.

Sporty

http://www.blasterforum.com/engine-13/blaster-engine-break-44174/

 

[sporty982000]

Thanks, However I could not find a video on it, maybe the video was removed ?

I seen a video about clutches.

 

[mjgnslngr]

Thanks, However I could not find a video on it, maybe the video was removed ?

I seen a video about clutches.

Really? i click on the link Slicker posted and its Right There!

 

[blasterboy32]

Yeah it was in that link slick posted. However will it hurt to do 4 or 5 heat cycles because I don't really have an area to ride a tank through it before going all out? Ill still try to go gradually when I do go to where I ride but it takes me a day to go through a tank and don't want to be there with my buddy's riding and have to baby it all day but I can if doing extra heat cycles wont take the place of it.

 

[Blaaster]

No need to baby it for 2 tanks, just no more than 3/4 throttle.

 

[blasterboy32]

No need to baby it for 2 tanks, just no more than 3/4 throttle.

Oh okay. I can deal with that.

 

[sporty982000]

I clicked on it again and I got the right video. weird. But glad I clicked on it again, the other time, I got a clutch video. Mayeb I clicked on the wrong one.

None the less. I seen the video.

Questions. Perhaps Kevin can answer this one.


Is there not a increased risk of damaging a rod or crank bearing ? with the revving , not under load? during a break in ?

Most mechanics I know would never do this, they recommend under load. meaning riding it.

Is this more or less to ensure proper fuel / air mixture, that its' not getting to hot ? Or to confirm that the piston ring gap and wall cylinder / piston tolerance is correct and not causing to much heat ?

Another question:

Will this effect the piston rings. Meaning. Is there a risk of shutting it down to soon and not allowing proper piston ring heating / compression ? and then letting it cool. repeating a few times. Can this effect the temper of the rings at all ? IS they the main factor to have a temp gauge ?

Or is the tempered piston rings, not effected by this heat up and heat down, effecting break in expansion, of the compression of the rings in the piston ?

I know, a few questions, but never heard of anyone recommending this before on piston engines.

Sporty

 

[slickerthanyou]

I clicked on it again and I got the right video. weird. But glad I clicked on it again, the other time, I got a clutch video. Mayeb I clicked on the wrong one.

None the less. I seen the video.

Questions. Perhaps Kevin can answer this one.


1.Is there not a increased risk of damaging a rod or crank bearing ? with the revving , not under load? during a break in ?

Most mechanics I know would never do this, they recommend under load. meaning riding it.

2.Is this more or less to ensure proper fuel / air mixture, that its' not getting to hot ? Or to confirm that the piston ring gap and wall cylinder / piston tolerance is correct and not causing to much heat ?

Another question:

3.Will this effect the piston rings. Meaning. Is there a risk of shutting it down to soon and not allowing proper piston ring heating / compression ? and then letting it cool. repeating a few times. Can this effect the temper of the rings at all ? IS they the main factor to have a temp gauge ?

Or is the tempered piston rings, not effected by this heat up and heat down, effecting break in expansion, of the compression of the rings in the piston ?

I know, a few questions, but never heard of anyone recommending this before on piston engines.

Sporty

Not sure if Ken will chime in or not, it's busy season....

However my experience is mixed. I believe it may increase the life of the bore, by how much?? I have no idea as to the wear factor.
I will do my best to give you my answers and let others chime in!

1. I don't believe it would put anymore stress on the rod or crank bearings. In fact I think the opposite less stress on the bearings, good or bad?? don't really have an answer for that.

2. I'm certain that when I have my Builder bore/new piston and set all the tolerances, that they are correct from the get go.
I guess you can say you could check to see what temp the motors running! but you could always do that as you ride too!

3. Really, if you are running a forged piston and do not let it warm up enough, -you probably know this however- it will expand faster than the cylinder and sieze. I honestly don't think it hurts the rings either way!

 

[blasterboy32]

justdid the second heat cycle and it got up to 202. so that seems normal. at what temp should i be concerned that its too hot? also it was in the sun this time maybe that changed it because the first time it was in the shade. do i have to let it cool completly after the third heat cycle too? and the re torque all the base nuts and head nuts and its good to go?