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2004 xr650l engine braking

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I have a 2004 xr650l and have performed daves mods. When riding on the road at steady speed when I completely let off the throttle without pulling in the clutch the bike engine brakes so well I rarely need to use my brakes. Is this normal? Will it hurt anything doing this or should I pull the clutch and hold until I come to a complete stop.

When I close he throttle completely it happens pretty abruptly and the bike will pitch forward. I assume this is normal , but just curious.

Edited by wvumountainman

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well it's up to you. If you use your engine for braking, it not only wears your engine but also your rear tire center. Personally, I would rather save my engine and rear tire and utilize the front brake for slowing and stopping. In order to do this, you need to nullify engine braking with neutral throttle while braking and minimize unnecessary downshifting. It helps quite a bit to go with a 320 rotor and galfer 1375's with stainless brake line if you ride a lot of street. This method becomes quite natural if you utilize trailbraking the way it was taught first by Freddie Spencer and now at the yamaha champions racing school run by Nick Ienatsch.

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Thank you. Is it normal for an XR650 to have such abrupt slowing when the throttle closed that the bike pitches forward somewhat? Anyone have this with their 650L?

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Thank you. Is it normal for an XR650 to have such abrupt slowing when the throttle closed that the bike pitches forward somewhat? Anyone have this with their 650L?

I'm currently breaking-in a new 2013 XR650L (100km so far), and if you are in the appropriate gear for the RPM's you are doing, the engine breaking you describe does not occur. You can only get engine breaking action that replaces the brakes by down shifting, & even then you still have to use the brakes in conjunction with the process.

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well it's up to you. If you use your engine for braking, it not only wears your engine but also your rear tire center. Personally, I would rather save my engine and rear tire and utilize the front brake for slowing and stopping. In order to do this, you need to nullify engine braking with neutral throttle while braking and minimize unnecessary downshifting. It helps quite a bit to go with a 320 rotor and galfer 1375's with stainless brake line if you ride a lot of street. This method becomes quite natural if you utilize trailbraking the way it was taught first by Freddie Spencer and now at the yamaha champions racing school run by Nick Ienatsch.

Natey, can you give a description of the tail-breaking method you mentioned, taught by Freddie Spencer?

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Thank you. Is it normal for an XR650 to have such abrupt slowing when the throttle closed that the bike pitches forward somewhat? Anyone have this with their 650L?

absolutely. That's completely inherent of a large thumper. The fact you can compression slide them into a corner and power slide out is what makes them so user friendly and fun.
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...it not only wears your engine but also your rear tire center. Personally, I would rather save my engine and rear tire and utilize the front brake for slowing and stopping.

People on various motorcycle forums keep propagating this myth about engine wear from engine braking.  What exactly gets worn any differently in your engine under engine braking than under acceleration, or just maintaining speed?  I really want to know.

 

As for rear tire wear, it's the acceleration that wears out my rear tires.  Engine braking is significantly more "gentle" on the tire than blasting away from traffic when the light turns green.  If there were a way to measure the difference in tire wear, it would likely be in the ballpark of knocking total miles down from 5000 to 4900 before the rear tire wears out.  That's completely insignificant in my book.

 

I use engine braking all the time on my singles and V-twins for gentle deceleration.  I can find no good reason not to do it. It's certainly better than pulling up to a stop in neutral or slowing down from speed with the clutch held in the whole time.

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People on various motorcycle forums keep propagating this myth about engine wear from engine braking. What exactly gets worn any differently in your engine under engine braking than under acceleration, or just maintaining speed? I really want to know.

As for rear tire wear, it's the acceleration that wears out my rear tires. Engine braking is significantly more "gentle" on the tire than blasting away from traffic when the light turns green. If there were a way to measure the difference in tire wear, it would likely be in the ballpark of knocking total miles down from 5000 to 4900 before the rear tire wears out. That's completely insignificant in my book.

I use engine braking all the time on my singles and V-twins for gentle deceleration. I can find no good reason not to do it. It's certainly better than pulling up to a stop in neutral or slowing down from speed with the clutch held in the whole time.

Thanks Scott. I appreciate your input. I too find it easier to engine brake gently from speed when coming to a stop light especially. I don't like guessing for the correct gear when the light turns green. However some people could say this is inexperience on my part, but I'm new to this bike and still learning its tall gearing. Edited by wvumountainman

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We better let all those drivers of 1,000,000mi+ tractor-trailers know that using the Jake is wearing out their engines.

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I have a 2004 xr650l and have performed daves mods. When riding on the road at steady speed when I completely let off the throttle without pulling in the clutch the bike engine brakes so well I rarely need to use my brakes. Is this normal? Will it hurt anything doing this or should I pull the clutch and hold until I come to a complete stop.

When I close he throttle completely it happens pretty abruptly and the bike will pitch forward. I assume this is normal , but just curious.

Seems normal but just to make sure you should make sure you don't have a seized caliper piston that's dragging.

Edited by thumpthis723

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I engine brake 

but you best be proficient if you use it on the street  and since you mention not being sure about starting gear what you don't want is to compression brake around a corner and be in a lower gear than you anticipated

 

off road compression braking is a real advantage down steep inclines where the brakes would start to fade in a big way

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We better let all those drivers of 1,000,000mi+ tractor-trailers know that using the Jake is wearing out their engines.

 

Completely different thing.

 

Do you know how an engine brake works? Pulling the manual decomp on a XR600R while slowing down from speed is essentially the same thing, but I wouldn't advise it, because it wasn't made to work like that and something will break.

 

Tractor-trailers also have limited braking capabilities on during long descents, and once the brakes are gone, there is no stopping them without crashing, controlled or otherwise.

 

Most tractor-trailer engines are also governed below 2,000 rpm too.

 

Anyone who wants to wind their XRL/XRR engine to a high rpm, or drop a gear then let it hold the engine hold the bike back on deceleration is welcome to it. Their money, but brakes cost less and are easier to replace. Just letting the throttle close and downshifting when the engine is near idle and repeating for the next lowest gear until stopping is not compression braking, it's just slowing down.

 

Scott Summers didn't like to run aftermarket cams because it threw his timing off in turns, but, he was racing.

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Yes, I do know how a Jacobs brake works. Once the compression is released, the piston pulls a vacuum in the cylinder until the exhaust valve opens again, so it's not completely different.

 

My point is that using-up the brakes to save an immeasurably small amount of wear on the engine is like spending $20 now to save $5 later. EFI cars shut the injectors off during engine braking to save fuel and they have been doing that since the advent of digital EFI 30+ years ago, yet the carburetor-era myth lives on that coasting in neutral will save gas.

 

Tractor-trailers also have limited braking capabilities on during long descents, and once the brakes are gone, there is no stopping them without crashing, controlled or otherwise.

 

So they use the engine.....as a brake.

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So they use the engine.....as a brake.

 

That's like apples to oranges. An industrial engine built to pull 80,000lbs+ has little more in common than just being a four cycle engine.

 

http://www.svfd.net/SVFD%20Files/Articles/Engineer/An%20engine%20brake%20is%20a%20hydraulically-operated%20device%20on%20a%20diesel.pdf

 

 

I have no idea what kind of stopping requires $20 to be spent on brakes "now." It certainly isn't any kind of stopping I do.

 

As far as the PO's question, if the bike is pitching forward, as described, a low gear at high rpm is being used. Either the PO doesn't know when to shift up and is doing the sport bike, I-like-to-ride-everywhere-in-second-gear thing or the bike is just being ragged on.

 

Using the engine to hold the bike back when riding down a steep hill, off road, is not what I'm talking about. Blasting into a turn at high rpm deceleration, so much that the rear tire breaks loose, is ragging on it. Blasting around town like a squid throttle on-throttle off, without so much as hardly changing a gear is what I'm talking about and is also ragging on it. A bike that is ragged on is not going to last nearly as long as one that isn't. In summary, ragging on a bike is just tearing it up, same thing.

 

I really don't care. If the PO doesn't understand how to shift or use the brakes that's not my problem. I'm just offering up that it sounds like the PO is being unreasonably hard on the bike if they are really concerned about it lasting, which seems to be the original concern.

Edited by Onederer
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Completely different thing.

Do you know how an engine brake works? Pulling the manual decomp on a XR600R while slowing down from speed is essentially the same thing, but I wouldn't advise it, because it wasn't made to work like that and something will break.

Tractor-trailers also have limited braking capabilities on during long descents, and once the brakes are gone, there is no stopping them without crashing, controlled or otherwise.

Most tractor-trailer engines are also governed below 2,000 rpm too.

Anyone who wants to wind their XRL/XRR engine to a high rpm, or drop a gear then let it hold the engine hold the bike back on deceleration is welcome to it. Their money, but brakes cost less and are easier to replace. Just letting the throttle close and downshifting when the engine is near idle and repeating for the next lowest gear until stopping is not compression braking, it's just slowing down.

Scott Summers didn't like to run aftermarket cams because it threw his timing off in turns, but, he was racing.

Perfect! Maybe I was misleading. This is exactly what I do, I'm at a steady speed, close the throttle, and downshift when at idle, or slightly above idle pace. I have been confusing normal slow down and compression / engine braking. I have no brake drag at all because when I pull the clutch it coasts fine, but when I close the throttle with no clutch the bike still slows down at a faster pace than say an automatic car that keeps coasting after throttle close. I drive a stick diesel truck and have a Foreman 500 that have the same effect, just different feeling on two wheels. Sorry for the noob questions and I appreciate everyone's help. Great forum!

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Perfect! Maybe I was misleading. This is exactly what I do...

Good!

I've seen people just stomping down on gear levers before, especially on ATVs with worn out brakes because the owners didn't want to repair the brakes. Guess what was going out next.

It's good you aren't. I managed 50,000 miles out of my XRL engine before it needed a rebuild. I rode it hard, but didn't abuse it. I think much more than that is possible with mostly street use and easy riding.

As far as automatic car transmissions, they have no physical connection to the engine during deceleration. Even if they have a torque converter cluitch, it disengages during deceleration and the turbine and impeller of the torque converter just have fluid passively passing between them. Nothing drives the engine, it's just built so the engine drives the transmission. It's the same reason an automatic car can't be push started, the engine doesn't turn. Now, some modern diesel trucks probably have automatics with engine braking capabilities, they just about have to or it would be difficult to manage stopping heavy loads.

Don't confuse auto clutch ATVs with CVT(fully automatic) equipped ATVs. An auto clutch system has a sprag clutch along with the centrifugal/plate clutch which provides engine braking. Not so with CVT.

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We better let all those drivers of 1,000,000mi+ tractor-trailers know that using the Jake is wearing out their engines.

funny you mentioned that. I logged over 2 million tractor-trailer miles between 1980 and 2000 and gradually evolved from having no jake to driving with a jake and using it discreetly, and finally, to having it on all the time. In terms of driving a semi, the jake helps with cutting reaction time and offers increase braking when the need arises. Helps keep you from running over those pesky fourwheelers who seem to think you can stop as fast as they can.To me it was all about safety and control and nothin to do with engine or tire wear. Motorcycles dynamics dictate a whole diff ballgame for me.

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Natey, can you give a description of the tail-breaking method you mentioned, taught by Freddie Spencer?

For sure I could give you a detailed description of trailbraking Freddie Spencer style, but it may be more beneficial to view http://fastersafer.com/ and search trailbraking freddie spencer and nick ienatsch. It took me a year plus to feel comfortable riding according to this method, but now it's autonomic with me. These sources will get you started and the rest is practice. 

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Jake brakes were actually developed to reduce wear on other components. They were a refinement of the already known benefits of compression braking in controlling heavy loads. Using a jake all the way down the mountain with a logging truck was much safer than using the brakes up half way down.

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