TE 250 RPMs

[glangston]

I'm just gettin out there trying to break the bike in and getting used to riding again after 30 years or so. What sort of rpms are we talking about in the break-in phase? And what are the practical limits of rpm on these bikes once they're broken in. It's hard to find this simple info.

[fitness2go]

How to break-in a bike is no simple task as there are 2 distinct camps when it comes to doing it.

"EASY" break-in method:

https://www.thumpertalk.com/forum/showthread.php?t=596398

"HARD" break-in method:

https://www.thumpertalk.com/forum/showthread.php?t=595983

Hope this helps,

David

[Beaver Cleaver]

How to break-in a bike is no simple task as there are 2 distinct camps when it comes to doing it.

"EASY" break-in method:

https://www.thumpertalk.com/forum/showthread.php?t=596398

"HARD" break-in method:

https://www.thumpertalk.com/forum/showthread.php?t=595983

Hope this helps,

David

Dave you are getting to politically corect, posting both camps thoughts and not even giving a recomendation for one or the other.?

[fitness2go]

You got me there! For the record, I used George's "EASY" break-in method because he told me so.

[Beaver Cleaver]

You got me there! For the record, I used George's "EASY" break-in method because he told me so.

All right then the fight is on. I am going to stand in Dave and Georges corner, Ride you take the spot diectly across the ring with Dan. Now remember boys no throwing rotten tomatos and lets have a good clean fight.?

[glangston]

OK, I did find some info. 12,500 rpms

I was just puttin around in the neighborhood cemetary first then took a ride down to the beach ....around 10 miles total. It felt like I was taking it easy, around 5000-6000 max rpm and around 40 mph. This naturally is not powered up yet. Stalled a few times ....

[NiceUserName]

Thank you for starting this thread glangston, I've been too shy to do so.

After reading both threads earlier this year with sweaty palms and much stress, we are doing middle of the road break in. I have been lectured to keep the rpms up, always. However, the 07 TE250 seems very happy at low rpms as well?

[Danceswithtrees]

It's really very simple. You want to seat the rings and you only have one chance on these finely honed nicasil cylinders. In order to due that well you need cylinder pressure to force the rings against the cylinder walls.

That means:

1. Don't let it sit and idle more than it takes to warm it up.

2. Run up and down through the gears using moderate to heavy moderate accelaration. This doesn't mean to redline it.

3. Use engine breaking when decellerating.

4. Don't lug it in too high a gear.

5. Don't run at constant or sustained speeds.

6. let it cool down and repeat.

7. Change oil.

[themattreid]

It's really very simple. You want to seat the rings and you only have one chance on these finely honed nicasil cylinders. In order to due that well you need cylinder pressure to force the rings against the cylinder walls.

That means:

1. Don't let it sit and idle more than it takes to warm it up.

2. Run up and down through the gears using moderate to heavy moderate accelaration. This doesn't mean to redline it.

3. Use engine breaking when decellerating.

4. Don't lug it in too high a gear.

5. Don't run at constant or sustained speeds.

6. let it cool down and repeat.

7. Change oil.

Awesome, I did mine the right way! ?

[NiceUserName]

It's really very simple. You want to seat the rings and you only have one chance on these finely honed nicasil cylinders. In order to due that well you need cylinder pressure to force the rings against the cylinder walls.

That means:

1. Don't let it sit and idle more than it takes to warm it up.

2. Run up and down through the gears using moderate to heavy moderate accelaration. This doesn't mean to redline it.

3. Use engine breaking when decellerating.

4. Don't lug it in too high a gear.

5. Don't run at constant or sustained speeds.

6. let it cool down and repeat.

7. Change oil.

Thanks - that's pretty much what my husband explained to me. I guess my question is after the break in period is this as critical? It was also explained to me that this type of 4 stroke behaves more like a 2 stroke and requires maintaining higher rpms. I don't ever intend to lug the engine, but I would like to not be paranoid about letting the rpms drop below 5000 if I need to creep through a section. On a 2 stroke if I have to creep through a section I feather the clutch with a little throttle to keep the rpms up - is this going to be the same type scenario with the TE? I’m very nervous about doing the right thing with this bike as I would like to keep it around for several years to come.?

[Danceswithtrees]

Thanks - that's pretty much what my husband explained to me. I guess my question is after the break in period is this as critical? It was also explained to me that this type of 4 stroke behaves more like a 2 stroke and requires maintaining higher rpms. I don't ever intend to lug the engine, but I would like to not be paranoid about letting the rpms drop below 5000 if I need to creep through a section. On a 2 stroke if I have to creep through a section I feather the clutch with a little throttle to keep the rpms up - is this going to be the same type scenario with the TE? I’m very nervous about doing the right thing with this bike as I would like to keep it around for several years to come.?

Lug it all you want. I do all the time in the really wicked stuff. I do like to let mine rev out in the open stuff. I don't have a TE(yet), but I really use the entire rpm range on my 250 xcf-w without fear.

[Gusgus]

My dealer has ridden Husky from day one and he has a total different way of "Break in" method.?

First you need some duct tape and exactly 2.7 lts of fuel....

Drain all the fuel from your bike...put in exactly 2.7 lts of fuel back in.

Tape your throttle wide open using the duct tape... put your bike on the side stand and fire it up.

When your bike runs out of fuel...or the bike falls over.. you're done.

Change the oil when its still hot.

Oh ya ...Let it cool off. Before riding again...most important.?

[themattreid]

My dealer has ridden Husky from day one and he has a total different way of "Break in" method.?

First you need some duct tape and exactly 2.7 lts of fuel....

Drain all the fuel from your bike...put in exactly 2.7 lts of fuel back in.

Tape your throttle wide open using the duct tape... put your bike on the side stand and fire it up.

When your bike runs out of fuel...or the bike falls over.. you're done.

Change the oil when its still hot.

Oh ya ...Let it cool off. Before riding again...most important.?

You can't be serious.

[Ruffus]

My dealer has ridden Husky from day one and he has a total different way of "Break in" method.

First you need some duct tape and exactly 2.7 lts of fuel....

Drain all the fuel from your bike...put in exactly 2.7 lts of fuel back in.

Tape your throttle wide open using the duct tape... put your bike on the side stand and fire it up.

When your bike runs out of fuel...or the bike falls over.. you're done.

Change the oil when its still hot.

Oh ya ...Let it cool off. Before riding again...most important.?

Psssssssssssst April fools day was last week:doh: ?

[silver_fox]

My dealer has ridden Husky from day one and he has a total different way of "Break in" method.

First you need some duct tape and exactly 2.7 lts of fuel....

Drain all the fuel from your bike...put in exactly 2.7 lts of fuel back in.

Tape your throttle wide open using the duct tape... put your bike on the side stand and fire it up.

When your bike runs out of fuel...or the bike falls over.. you're done.

Change the oil when its still hot.

Oh ya ...Let it cool off. Before riding again...most important.?

Nice. ?

[Beaver Cleaver]

It's really very simple. You want to seat the rings and you only have one chance on these finely honed nicasil cylinders. In order to due that well you need cylinder pressure to force the rings against the cylinder walls. That means:

1. Don't let it sit and idle more than it takes to warm it up.

2. Run up and down through the gears using moderate to heavy moderate accelaration. This doesn't mean to redline it.

3. Use engine breaking when decellerating.

4. Don't lug it in too high a gear.

5. Don't run at constant or sustained speeds.

6. let it cool down and repeat.

7. Change oil.

OK don't get me wrong here I am not picking on any individual nor am I trying to start an argument but this comment seems to be a recurring theme on the "hard vs easy" break in method and I don't understand where it comes from so if someone could explain it to me I would appreciate it.

People keep saying that you need cylinder pressure to force the rings to seat against the cylinder wall. Now as far as I know the rules of physics still apply inside the cylinder of an internal combustion engine and that being the case it means that fluids (and yes air is a fluid also) will follow the path of least resistence and the path of least resistence is going to be straight down the cylinder wall around the outer perimeter of the ring. In order for the ring to be expanded by cyinder pressure the fluid is going have to make two 90 degree bends across a longer path so how is that possible? Now even if there is some way for the gas to get behind the ring the best that you could hope for is that the pressure on the back side of the ring is equal to that around the outer perimeter (which is highly unlikely given the path that it has to travel) and since the outer perimeter has more suface area that means that the force would be greater on the outside of the ring and it would try to collasp it. The only way that I can see that cylinder pressure could be used to force the rings out would be to create a less restrictive path to the ID of the ring which could be accomplished by using a gas ported piston but Husky doesn't do that. It is my contention that the only thing forceing that ring against the cylinder wall is the ring tension. I am perfectly willing to listen to anyone that things this is a wrong analogy but I have yet to hear anyone come up with a sensible answer to this question.

[Ride]

Some bikes I have ridden hard from the start because i wanted to ride. Some I have taken a little easier on. None have had issues. I really do not think it matters that much. Don't over heat it and ride it semi nice for the first tank or two and let-r-rip. IMHO.

I don't think I ever really endorsed the break it in hard method but I did throw it out there and it does seem to have merit in some circles. ?

[Ride]

OK don't get me wrong here I am not picking on any individual nor am I trying to start an argument but this comment seems to be a recurring theme on the "hard vs easy" break in method and I don't understand where it comes from so if someone could explain it to me I would appreciate it.

People keep saying that you need cylinder pressure to force the rings to seat against the cylinder wall. Now as far as I know the rules of physics still apply inside the cylinder of an internal combustion engine and that being the case it means that fluids (and yes air is a fluid also) will follow the path of least resistence and the path of least resistence is going to be straight down the cylinder wall around the outer perimeter of the ring. In order for the ring to be expanded by cyinder pressure the fluid is going have to make two 90 degree bends across a longer path so how is that possible? Now even if there is some way for the gas to get behind the ring the best that you could hope for is that the pressure on the back side of the ring is equal to that around the outer perimeter (which is highly unlikely given the path that it has to travel) and since the outer perimeter has more suface area that means that the force would be greater on the outside of the ring and it would try to collasp it. The only way that I can see that cylinder pressure could be used to force the rings out would be to create a less restrictive path to the ID of the ring which could be accomplished by using a gas ported piston but Husky doesn't do that. It is my contention that the only thing forceing that ring against the cylinder wall is the ring tension. I am perfectly willing to listen to anyone that things this is a wrong analogy but I have yet to hear anyone come up with a sensible answer to this question.

Actually combustion pressure does in fact make the ring expand onto the cylinder surface. The downward pressure tries to push the ring out of the landing as as it does it pushes it out. It is designed to do this and it is how it seals. I don't think this is disputed among engine builders etc.

[drzmike1]

I'm no physics whiz, but I think it has to do with the fact that when the crank throw is horizontal and the rod is at an angle there is going to be sideways force on the piston. The more pressure the more force.

[Danceswithtrees]

A paragraph from an article talking about proper end gap in building race engines.

"The reason the gap is there is that the gas pressure has to get behind the ring to provide the sealing pressure that forces the ring against the cylinder wall. These forces are way, way, greater than the static ring tension described above. These forces push the ring "down and out" i.e. against the bottom of the groove and out against the cylinder wall."

added from Reher-Morrison Racing Engines

Reducing the tension of the top ring and drilling gas ports is a win-win situation. A standard D-wall .043-inch top compression ring has a .210-inch radial thickness; you can certainly run this ring without gas ports because it has more than enough static radial tension to push the ring face firmly against the cylinder wall. But that radial tension adds to the engine’s internal friction because the ring drags against the cylinder wall every time the piston rises and falls. In fact, we really only want the top ring to seal against the cylinder wall primarily on the power stroke; on the other three strokes, it’s just along for the ride. So in this example, it’s an excellent trade-off to use low-tension top rings with a .160-inch or .170 inch radial thickness, and then use gas ports to apply cylinder pressure directly to the back of the rings for sealing only when it’s needed.

Among the misconceptions about gas ports is the mistaken belief that gas ports increase ring wear. That’s just wrong. In fact, gas ports allow you to reduce ring drag while sealing the cylinder more effectively. All piston rings rely on cylinder pressure for sealing; gas ports just apply the pressure more efficiently. We rebuild hundreds of racing engines, and typically see less piston ring wear in engines with gas ports than in engines with conventional rings. That’s because the engines with low-tension rings and gas ports have less drag on the three strokes when absolute sealing isn’t needed. The gas ports also allow the top rings to depressurize quickly; after the exhaust valve opens, cylinder pressure falls dramatically and the pressure behind the ring dissipates.

So you are right in that gas porting increases ring sealing, but ring pressure is still increased due to cylinder pressure, which is greater when an engine is under load.