Author Topic: RPM unstable  (Read 10361 times)

edmund goh

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RPM unstable
« on: September 13, 2013, 07:26:21 AM »
Hi all,

I had a bad experience with my 2013 f800gs, the RPM kept revving from 1-3 x 1000 rpm on idle with or without clutch actuation.

I tried revving it to the max (well silly me, thought its like CRT tv give it a knock and it works). But it doesn't work(of course)

It happen when i was close to my 10000km servicing, so i suspect it was air filter clogg so i replaced it with k &n air filter. Plug in with the GS-

911 i found in the engine cluster, selection theres an idle acutator calibration so i tested it out.

After running the bike again which i did the idle actuator test and air filter change and i found that the rpm is stable again. The air filter seems

like able to make my bike more torquey(thats to me). The problem is sloved.

I like to highlight this so as to get more rectification ideas and situation if anyone is facing the same problems.

Acutally what i want to ask are, whether this situation(rpm unstable), is it the idle actuator, airfilter or something else.

Rgds,
ed 

bikecrazy5

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Re: RPM unstable
« Reply #1 on: September 15, 2013, 09:58:41 PM »
hi
the idle actuator is a small piston type action which needs recalibration from time to time.the bike teaches the throttle position each time you switch your bike on, that is why it is utmost important not to touch you throttle on start up.now what happens is it almost tends to get stuck as it does not always use its full reach depending on the temperature of the bike on start up...so i would say the t.p.s sensor was your issue.

edmund goh

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Re: RPM unstable
« Reply #2 on: September 17, 2013, 03:23:47 PM »
Throttle position sensor? I see that explains y. Thanks a lot. But if I hit the kill switch button before shutting down. Is there any effect or impact on the engine.

It is beacuse my riding group were still paranoid on the action of the 2013 kill switch. Some of the people kill switch got stuck and cannot
start bike, some even cannot turn off engine.

to me the logic is like a computer you hit shut down before turning the ignition key.

bikecrazy5

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Re: RPM unstable
« Reply #3 on: September 17, 2013, 11:55:53 PM »
your kill switch is a emergency cut off switch...some people believe in killing the bike before turning the ignition off...but what i have noticed isa sometimes it confuses the ecu...according to bmw u must just turn ur bike off at the ignition so it has its few seconds to shut down the ecu AS a computer does when you push shutdown in the start bar.where as the kill switch just cuts it out. if u look on a f800 u can actually see it shutting down.

edmund goh

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Re: RPM unstable
« Reply #4 on: September 18, 2013, 11:39:51 AM »
Thanks bikecrazy5. I can share with my friends. Btw what you are riding? Ya great with the knowledge of the bike.

StephanT

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Re: RPM unstable
« Reply #5 on: September 19, 2013, 03:22:28 PM »
Thanks bikecrazy5. I can share with my friends. Btw what you are riding? Ya great with the knowledge of the bike.
I have a different view.. hitting the kill switch on a K024 chassis motorcycle (such as a F800), does nothing but stop the motor from running... The kill switch on this generation of motorcycles is just an input to the ECU..., just like the side stand switch etc.

When you hit the Kill switch nothing goes OFF, except that the engine stops running... you can still talk to the ECU and all other functions are active and communicating...

On the older bikes, like the 1150's and 650 singles, that's a completely different story... there the sidestand switch and the kill switch are hard wired into the energising circuit of the main power relay... Hit either of them and power is cut to the ECU - completely...

best,
Stephan
currently riding:
    BMW F850GS Adv - slightly modified
    HD Pan America - development bike for ezCAN

edmund goh

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Re: RPM unstable
« Reply #6 on: September 20, 2013, 01:48:27 PM »
I see thanks for replying also stephan. This topic in my riding group kept going and going and ........

Btw im open for opinions, wanting to know more actually of how the bike electronics work.

And the 2013 bmw controls sucks!(sorry for the vulgar), the plastics feels cheap (my 15years old lego plastics feels better)  and lots of the switches got stuck. I have got the light switch which is trigger type stuck in the high beam postition, info switch depress and stuck. My riding group one of the fella got mulitple failure at the left hand instrument switched, signal switch unable to cancel, high beam stuck, horn depress and the honking kept going. The right worst.... switch stuck at engine cut off, some feels the engine start detent but nothing happens and one of the guy cannot kill off engine with the switch.

But i like the way they organise the components to behave, example light switch tigger type (high/low/passing) beam all integrated. Signal switch left and right integrated together apart from previous f800gs from other years. Engine kill switch and starter integrated to  the simple rocker operation.

Although the switches this year kinda cool for its operation, but i think its a safety harzard especially the engine kill switch.

Rgds,
Ed....   

edmund goh

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Re: RPM unstable
« Reply #7 on: November 22, 2013, 04:06:40 PM »
Hi everyone,

Its me again with the rpm unstable, well it happened again to my f800gs. so i dont think its the kill switch now.

This time it got worst the bike will stall at idle and some gears that i kick doesnt engauge.

I plug in with the gs 911, under the engine wording theres  the idle actuator calibration. i tried it but running the bike a while doesnt seems to

solve the problem. This is when i saw the adaptations reset wording, i tried clicking on it which say its for compensating components tolerance.

While doing the resetting the gs911 prompt the user to placed it on main stand and engauge the every gear for 5 to 10 secs.

Upon completing the 6 gear on my bike, the other instruction were to turn the power off for the ecu to capture the new values.

The gs911 also shows the value for each gear in volts, the instructions states that every gear the value were different, eg. gear 1 0v, neutral

0v, gear 2 1.2v, gear 3 2.1v..... and till gear 6. so this leads me to think the gear were link to the TPS(throttle valve potensiometer)?


After the adapatations resetted and idle actuator resetted, the bike seems to run fine.

 

edmund goh

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Re: RPM unstable
« Reply #8 on: November 22, 2013, 04:10:58 PM »
The adaptations consist of the following:

Engine or gearbox

Throttle body

gear sensor

TPS( Throttle-valve potentiometer

Lamda sensor

Fuel injectors

Other changes in and around the fueling system