RPM's increase when clutch is engaged

[dcarver]

Put your FJR on the center stand.

Start and put in 1st gear, release clutch.

Use throttle lock to set rpm to approx 1,500.

Disengage clutch and note rpm decrease.

Engage clutch and watch rpm increase.

Crapola. Evidently this board doesn't like iFrame embed code from Vimeo -

so CLICKY

Towards video end, you can see the speedo too.

Weird.

 

[SkooterG]

Bad clutch bearing? Sure makes a racket when you pull in the clutch.

Makes sense though. Not only are you weird, but your FJR is too.

 

[wfooshee]

At 1500 RPM in first there is such a small throttle opening that the difference between driving the rear wheel or not is enough to change the engine speed. Changing the load without changing the throttle results in an RPM change every time. Always.

I'm also assuming that by "disengage the clutch" you mean release the lever, which actually engages the clutch, as in causes it to transmit torque to the transmission. We don't see the clutch lever, we just see the tach and hear the motor. if you actually mean disengage the clutch by pulling the lever, then my explanation goes out the window:

 

[DJB]

I guess the real question is why do we care? If the bike is doing it's job who cares how they programmed the ECU? You need to find more relevant things to rant about.

 

[CAJW]

I guess the real question is why do we care? If the bike is doing it's job who cares how they programmed the ECU? You need to find more relevant things to rant about.

rant/rant/

Verb:Speak or shout at length in a wild, impassioned way.

Noun:A spell of ranting; a tirade.

rel·e·vant/ˈreləvənt/

Adjective:Closely connected or appropriate to the matter at hand.

Synonymsertinent - appropriate

ob·ser·va·tion/ˌäbzərˈvāSHən/

Noun:

• The action or process of observing something or someone carefully or in order to gain information.
• The ability to notice significant details.

I would offer our good DC here is merely offering an observation, not a rant. He has always been a keen observer.

(or maybe a little weird, but aren't we all?)

 

[HotRodZilla]

Um...Carver is a LOT weird. How the hell does one even know this happens? You have snow at your house Don???

 

[BikerGeek99]

Don - are you high?

Is it Friday yet??

 

[beemerdons]

Um...Carver is a LOT weird. How the hell does one even know this happens? You have snow at your house Don???

Trust me AJ, it's definitely snowing inside of Carver's head; I mean, it's a fecking blizzard! jes' sayin' and nuff' said!

 

[carlson_mn]

Confused as to what is going on here

 

[Fred W]

Towards video end, you can see the speedo too.

Yes you can. Is this an early April fools joke? The speedo is only dropping from 25mph to 15mph when the engine speed drops. This kind of suggests that the clutch is not actually being disengaged. :huh:

 

[Spud]

This should immediately be reported to the NHTSA. Under certain circumstances, this problem would lead to serious injury or death. Let's get a campaign started--I'll run home at lunch and see if mine does it too. We need to find out if it's a Gen 1 issue too. Volunteers?

RECALL!!!!!!!!

 

[Geezer]

I am not going down to the garage to try that, not even in February with a couple feet of snow on the ground. :huh:

 

[dcarver]

At 1500 RPM in first there is such a small throttle opening that the difference between driving the rear wheel or not is enough to change the engine speed. Changing the load without changing the throttle results in an RPM change every time. Always.

I'm also assuming that by "disengage the clutch" you mean release the lever, which actually engages the clutch, as in causes it to transmit torque to the transmission. We don't see the clutch lever, we just see the tach and hear the motor. if you actually mean disengage the clutch by pulling the lever, then my explanation goes out the window:

Engaging the clutch, placing load on the engine, raised the rpm - that's what I found *unusual*. Disengaging the clutch resulted in lower rpm - opposite of what seems logical, where logic would say loading a throttle locked engine should drag engine rpm down.

I guess the real question is why do we care? If the bike is doing it's job who cares how they programmed the ECU? You need to find more relevant things to rant about.

rant/rant/

Verb:Speak or shout at length in a wild, impassioned way.

Noun:A spell of ranting; a tirade.

rel·e·vant/ˈreləvənt/

Adjective:Closely connected or appropriate to the matter at hand.

Synonymsertinent - appropriate

ob·ser·va·tion/ˌäbzərˈvāSHən/

Noun:

• The action or process of observing something or someone carefully or in order to gain information.
• The ability to notice significant details.

I would offer our good DC here is merely offering an observation, not a rant. He has always been a keen observer.

(or maybe a little weird, but aren't we all?)

Thanks CAJW! Not a rant, just found the behavior unusual, like most of the inmates on this board!

Um...Carver is a LOT weird. How the hell does one even know this happens? You have snow at your house Don???

Geesh, not yet, but the dirt road is a mud bath.. Now then, where's the phone number for that female mud wrestling troupe?

Don - are you high?

Is it Friday yet??

Yes, high on life!

Towards video end, you can see the speedo too.

Yes you can. Is this an early April fools joke? The speedo is only dropping from 25mph to 15mph when the engine speed drops. This kind of suggests that the clutch is not actually being disengaged. :huh:

No Aprils fools joke - try it yourself, trust me! :rofl: You will be amazed with what you find out, causing you to research the ends of all technology to reach a reasonable hypothesis...

This should immediately be reported to the NHTSA. Under certain circumstances, this problem would lead to serious injury or death. Let's get a campaign started--I'll run home at lunch and see if mine does it too. We need to find out if it's a Gen 1 issue too. Volunteers?

RECALL!!!!!!!!

Exactly! This is world crisis!

 

[beemerdons]

So Carver, is the Creston harvest of the Fall mota crop finally completed and stacked in the barn, so you can now concentrate on other important and pressing matters.? That SLO Wowee must be killah, two hits and the paper turns brown!

 

[dcarver]

So Carver, is the Creston harvest of the Fall mota crop finally completed and stacked in the barn, so you can now concentrate on other important and pressing matters.? That SLO Wowee must be killah, two hits and the paper turns brown!

Come on BD, give it at try and say I'm wrong!

I freakin' DARE you!

This issue is huge, and will motivate earth from planned orbit unless root cause problem is identified!

So put Lucy on center stand, start, drop in gear with throttle locked at 1,500, then engage/dis-engage clutch...

double dog dare!

 

[SaharaJp99]

Maybe the resistance of the oil when the clutch is opened up, ie disengage, is enough to bog down the engine just a tad. Once you engage the clutch it pushes the oil out from between the plates and is solid, with less surface area spinning through the oil. Once the clutch is engaged and the rear wheel spinning, I think the centrifical force of the rear wheel would keep the rpms up without the tire touching the ground with no "real" load, and the load of the oil would be more than that of a spinning wheel.

Just a thought and I'm probably way wrong and definitely not an engineer.

 

[wfooshee]

Yeah, oil is so much harder to move than gears and wheels and stuff.

Still haven't performed the experiment, but when I do, I will do it with the bike cold, and then warmed up, and see if either exhibits the Behavior, and if there's a difference.

Science, y'know.

 

[SaharaJp99]

I sense the sarcasm.

You'd be suprised what kind of a load oil can add to an engine. Right now, John Deere has a recall out to replace all of the hydraulic and engine oils in their new skid steer line that are operated in sub-freezing temps. They are switching to a wider range viscosity fully synthetic oil. Why? Because with normal dyno oil in there it puts enough drag on the engine and hydraulic pumps that the starter can't spin the motor fast enough for it to start. Now I'm sure if oil didn't make a difference Deere would love to save the 100's of thousands that this is costing them.

 

[FJRBluesman]

Ok, a couple observations:

1) I concur, dcarver is weird...er than most.

2) Towards the end of the vid, the speed-O was also increasing/decreasing. So that would tell me your mileage will also suffer. Just sayin'.

3) This is definitely a Gen2 issue. :huh: