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Knock sensor? GS-911 - Printable Version

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Knock sensor? GS-911 - Ulvetanna_imp - 12-01-2016

I recall from 2013 a heated debate about whether the CB1100 had a knock sensor. This had to do with acceptable fuels, and whether any power benefit could be had with higher octane.

Obviously, a knock sensor allows an engine to be run safely on regular but benefit from high-octane fuels by advancing ignition timing for a power increase.

I don't know for sure about this, I think the owner's manual did not mention a knock sensor (it would need four), but I just received a Hexcode GS-911 ECU interface for my F800GS, and it has a wealth of information about the Rotax engine and the bike's systems.

Never thought about it as I always run the recommended 91 octane, but the GS's engine has twin knock sensors, meaning it can be run on lower octane fuels safely (to a point).

They show up in the status display during self-check along with tons of other stuff. Good tool to have for bikes using extensive computer control.

One can also clear faults and reset service reminders. I have no intention of taking mine to a dealer so this tool was essential. It's especially needed to check and cycle the ABS unit.


RE: Knock sensor? GS-911 - Lord Popgun - 12-01-2016

The US wiring diagrams do not show a knock sensor on any model.
While looking at the diagrams, I noticed on the '14 diagrams that there is a thermistor. It is connected to ground on one side and the other goes through the fuel pump/Fuel level sensor connector straight to the meter. The input to the meter is just labeled Thermistor.

Any idea what it is for? I haven't searched the manual yet, but couldn't find it in the lights/metesr/switches section of the manual.


RE: Knock sensor? GS-911 - Ulvetanna_imp - 12-01-2016

(12-01-2016, 09:29 AM)Lord Popgun_imp Wrote: The US wiring diagrams do not show a knock sensor on any model.
While looking at the diagrams, I noticed on the '14 diagrams that there is a thermistor. It is connected to ground on one side and the other goes through the fuel pump/Fuel level sensor connector straight to the meter. The input to the meter is just labeled Thermistor.

Any idea what it is for? I haven't searched the manual yet, but couldn't find it in the lights/metesr/switches section of the manual.
No, that is interesting. I am guessing this is part of a fail-safe system; if the fuel tank or pump temperature exceed limits, the engine shuts off. It could prevent a tank explosion due to vapor being ignited under pressure, which is the case in CA bikes.


RE: Knock sensor? GS-911 - Lord Popgun - 12-02-2016

That make sense Wolf. I can't find any mention of it in the manual. I looked through the fuel system section and nothing. I looked in the parts fiche and couldn't find it either. I guess its part of the fuel pump assm.

Interestingly I did notice that the '14s meter assm. communicates with the ECM via a bi-directional serial data line. Man, you '14 guys get all the cool stuff. Smile And yes, there is troubleshooting for it if there are problems.


RE: Knock sensor? GS-911 - Ulvetanna_imp - 12-02-2016

(12-02-2016, 01:17 AM)Lord Popgun_imp Wrote: That make sense Wolf. I can't find any mention of it in the manual. I looked through the fuel system section and nothing. I looked in the parts fiche and couldn't find it either. I guess its part of the fuel pump assm.

Interestingly I did notice that the '14s meter assm. communicates with the ECM via a bi-directional serial data line. Man, you '14 guys get all the cool stuff. Smile And yes, there is troubleshooting for it if there are problems.
Glad I got the '13! I prefer a one-way conversation. ROFL

But I tell you this GS-911 is remarkable, the CANBUS setup (which almost all BMW bikes use now) is great for interaction with the bike's systems, checking fault codes, doing self-tests, clearing service reminders, getting all sensor data in real time. It's the wave of the future.

There is something similar for Japanese bikes, I need to look into that.Beer


RE: Knock sensor? GS-911 - Lord Popgun - 12-02-2016

I have the Healtech OBD-H01 tool for Hondas. You need a PC to use it. Won't work with Apple operating systems. Works with Honda outboards too. Their site is http://www.healtech-electronics.com


RE: Knock sensor? GS-911 - Ulvetanna_imp - 12-02-2016

(12-02-2016, 01:57 AM)Lord Popgun_imp Wrote: I have the Healtech OBD-H01 tool for Hondas. You need a PC to use it. Won't work with Apple operating systems. Works with Honda outboards too. Their site is http://www.healtech-electronics.com
Ah yes, I have seen that one before. Gonna have to get one. Thx Thumbs Up


RE: Knock sensor? GS-911 - the Ferret - 12-02-2016

Popgun, what does the healtech do? Couldn't a shop have used that to disgnose the idle problem on euro CB's? Or is it not made for that?


RE: Knock sensor? GS-911 - Ulvetanna_imp - 12-02-2016

Ferret, it is an OBD interface and does the same diagnosics as the factory unit. You can look at realtime values of all sensors, test systems, reset service reminders, and view/clear fault codes. The BMW does not use an OBD connection so you would need something like GS-911 for those bikes.


RE: Knock sensor? GS-911 - Lord Popgun - 12-02-2016

Its a diagnostic tool that plugs into the DTC (diagnostic connector) and reads out all the codes and a bunch of engine parameters. Honda uses their own HDS tool. Don't know about the bike dealers, but the Honda outboard dealer told me the tool was expensive and only dealers could get one. But now Healtech has one. At least one other member here has one as thats how I found out about it.

It will read and record parameters while the bike is running too and you can play them back. Heck, you could go for a ride and record them.

I have not plugged it into either of my bikes as I haven't needed too. But, the software has some example files from Honda bikes that you can play. I played 2. One a normal run, and one with something wrong, but I can't remember what. There is a LOT of data and I didn't know what it all meant.

You can hover the mouse pointer over a data cell and it tells you what the data is though. I think the site has pics of the data screen so you can look at it.

It is not very big and comes in a nice little case. A really miniature version of a, say, power drill case. Its cute Wink

I guess it would be smart to do a run while I have no problems in case of something wrong later. Maybe a Winter project for both bikes.

I installed the software on a crappy old notebook PC. We talked about this thing somewhere but I don't feel like searching for the thread right now Smile

I'm not a car mechanic, but it seems with some diagnostic tools and an exhaust gas analyser a decent tech would be able to find most running problems. But if some of the idle problems are ECM coding, well, a tech can't do much about that and Honda should step up, IMO.
For those not in the know and are wondering what Ulvetanna (or Wolf) is talking about, BMWs use a CANBUS system. Here is a link to basically explain it. [url=http://www.bmw-motorrad.com/com/en/index.html?content=http://www.bmw-motorrad.com/com/en/technology_new/item_can_bus.html&notrack=1]http://www.bmw-motorrad.com/com/en/index...&notrack=1