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Discussion Starter #1
Hi All..!

I've got a problem with the speedo on my bike.

Everything was working fine up until a few weeks ago but i now have an issue where the speedo will work fine up till about 80km/h (approx) and then it will sit on zero after that.
At times i can see the speedo flick to the correct speed and then go back to zero.
I've also noticed that when my speedo isn't working (or reading 0km/h) that the total km's (trip computer) won't count up too.

Where do i start to diagnose this problem?
Any assistance would be greatly appreciated.

In case it's relevant, my bike is fitted with a PC3 and Arrow pipes.

Thanks!
 

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Discussion Starter #3
Thanks wnehme!

I'll check them out. But i would have thought the fuses wouldn't be related because the speed is showing at times?
Wouldn't the display never show if the fuse is gone?
 

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Since the problem is intermitent, it sounds more like a loose connection than a bad fuse. I'm not sure how the speedo and odometer get its signal or where it gets it from but I would start there. Find a shop manual. Is there some sort of speedometer or odometer sending unit located in the wiring harness?

Since it is not a mechanical connection to the wheels there must be something the reads off the crank shaft, front sprocket, or something that is turning that generates an electric signal to send to the instrument cluster.

CAG
 

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Discussion Starter #6
Thanks for the help guys..
I'll be looking at it this weekend.
My first thought was a loose connection, so i'll start there.

If anyone has a manual or links to help me out... please post them here or pm me.
 

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I think it is your speed sensor also. I have a shop manual for a 750 but maybe it would help.

SPEED SENSOR
If the speed of the motorcycle is not indicated on the
instrument panel, proceed as follows:
• Check the condition of the fuse 3.

If the fuse in question is in good condition, proceed
with the check of the speed sensor as follows:
1) Remove the sensor from the motorcycle as described
in the “F4 workshop engine manual (Code
8000A1592).
2) Disconnect the connector, check that there 10 kΩ is
measured between terminals (1) and (2) of the connector

CAG
 

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Discussion Starter #8
Thanks CAG..!

That information is very helpful..!

I've managed to find an F4 engine workshop manual but it's not the code you supplied and makes no mention on how to remove the sensor.
I'll keep looking though.
 

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Discussion Starter #9
An update with the the problems i'm experiencing....

I've checked the fuses and they are all ok. I've even changed them around in case they were faulty and still no change.
I've checked the speedo sensor and it looks fine.

What i failed to mention originally is that i've got a speedo healer installed.
I've checked the earth from the speedo healer and all looks good.
The one thing i haven't checked is the line which is connected to my fuse box. Could this be causing any problems?

One thing i've noticed now though, is that my low beam and high beam headlights don't work anymore?
The park light or day riding light does work. The globes have been checked and they are fine.
To make things worse, i've no longer got working left hand side blinkers (front and rear). I think this may have to do with a faulty relay because the dash doesn't show a flashing indicator light when i switch to left side blinkers (the light stays on solid).
The dash shows indicator flashing when using the right side blinkers.

Am worried i may have an electrical fault now?
Has anyone experienced this sort of problem before?

Thanks...
 

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Discussion Starter #10 (Edited)
I was supposed to take my bike to the mechanics so he can have a look at the above problem but he's now informed me he can't look at it till the first week of the new year.
So i'm going to have another go at sorting it all out. I don't want to be without my bike for another 3+ weeks.

In relation to my blinker issue, can anyone tell me where to start looking to get my blinkers working again?
As stated above the indicator light on the dash stays on solid (but nothing on the actual blinker) when i switch to left signal but everything is fine when using right indicator..
 

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When you mention that the speedo flicks up to the correct speed and then goes back to zero you may be describing the fault code system on your bike. I've seen this happen on a 1999 R1 and a 2002 R1 and your description of what you are observing seems to be the same. If it is the case (and this is only a guess) that the rev counter is coming up to say 7000 rpm (for example) and then falling back to zero after a few seconds then I would refer to the workshop manual and check the 7000 rpm fault code. This will tell you where to start looking for the fault. Now I know this system is on the current R1s and I'm not sure that this system is on the MV you have but I hope this helps solve the problem you are experiencing.
 

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Lordy, what a rat's nest you've got going. Usually when a turn signal doesn't blink it's because a bulb is bad and the whole circut is broken. On my Duc 1098 if one bulb goes out the whole turn signal system won't work, right and left. So check the bulbs on the left. The wiring on these things is so damned complex and it seems as though everything is interdepedent upon everything else. Makes it tough the run down the fault.

You mentioned that your headlight is also out. If the turn signals get their power from the same feed then perhaps that's a place to look/start.
 

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The common denominator in all your problems is that they are all related to the instrument cluster. Headlight, blinkers, speedo etc. I would start there by checking the connections to the wire harness. Or, if possible, plug a different instrument cluster into your harness. At least that way you could eliminate the cluster as the source of your problem.

Remove the speedo healer and go back to original configuration first.

CAG
 

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Discussion Starter #14
Thanks for the comments/assistance guys.

I'm going to remove the speedo healer first and put it back to original configuration as CAG recommended.
I hadn't checked the left hand side bulbs yet, so will get on that too.
Hopefully it is only blown bulb causing the indicator problems.

have downloaded a copy of the chasis workshop manual which will help me out a little also.
When i do finally figure out what's causing me these problems, i'll be sure to post up my findings.

Thanks again for all the information..
 

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Hey MV's are notorious for intermittent blinkers you describe.
They use beautiful sliding, non plug connectors for easy removal, but can be finnicky.
On the aerlier 750's the connectors are up under the mirror stems where they meet the fairing. Loosen and jiggle with key and blinker switch on, and see if this works.
On 1000s they are down at the base of the fairng arms and you have to tighten the allen bolts just right.
Once you are aware, no problems, but catches everyone.
 

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Discussion Starter #16
MVASyd said:
Hey MV's are notorious for intermittent blinkers you describe.
They use beautiful sliding, non plug connectors for easy removal, but can be finnicky.
On the aerlier 750's the connectors are up under the mirror stems where they meet the fairing. Loosen and jiggle with key and blinker switch on, and see if this works.
On 1000s they are down at the base of the fairng arms and you have to tighten the allen bolts just right.
Once you are aware, no problems, but catches everyone.
I had planned on checking those connections again this weekend when i have another go at sorting out my bike problems.
I noticed originally when I had taken off the fairings that all the blinkers didn't work (with nose fairing off) and i assumed it was to do with the connection under the mirror stems (breaking the circuit cause it wasn't connected). They are 'gold' in colour and I did clean the contact zone before replacing the fairing.

Thanks for the heads up though, I'll check it out!
 
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