Stalling and stuttering at motorway speeds.

[Mr Bump]

Had a quick look at the wiring diagram for this model.
It shows a crank sensor.
I know this is probably the coil pickup
I work on cars and crank sensors are common for failing when hot.

Good shout. Well worth a look.

Olly

[Robw]

Although a different bike, I had a similar problem on my gpz900. It would randomly cut out and take a while to get going. I went through all the things that you have and eventually found out it was the pickup coils on the left hand side of the crank. I replaced them and it worked perfectly from there.
Rob

[Wardy]

Update.
Hi All.
I must admit I am not very good with electrics so testing volts at coil inputs etc is a dark art to me and Ralph had already gone over most of the electrics, except the Ignition coil, rotor and pick up, which according to the internet these bikes can have problems with.
So after a good search on the internet I found that for the windings alone it’s about £360, the rotor a similar price. I don’t earn much so this was out of the question.

I went to Jaks and had a moan and he suggested I start again from scratch and re-examine things that won’t cost me a penny and this is where it gets embarrassing.
I decided to once again take the carbs off and give them a going over – but something Jak said stuck in my mind. Now this particular thing I took off I have taken off at least twice already and both times blew it through with about a ¼ can of carb cleaner so to all purposes it looked clean and healthy.

Anyways Jak said to take it off and blow through it, which I did and sure enough it was blocked enough to only allow a very little bit of wind go through it. (Have you guessed yet).
As the tank was off the bike I opened the fuel tap to check flow and fuel ran freely. I attached the fuel line and opened the tap and the fuel just about tricked out, like a really old man having a piss.
If you haven’t guessed yet, and despite to the eyesight being clean and clear – it was the aftermarket fuel filter I had put on. It wasn’t clean at all but obviously full of almost clear gunk, stopping the flow to the extent on a long open throttle the carbs ran dry.

I have since replaced the fuel line, with a brand new filter, took it for its normal run (twice) and despite my best efforts I could not make the bike break down, so touching wood, I am hoping the fix really was this simple.

I cannot tell you how thoroughly embarrassed I am writing this message. I really should of known better and if wasn’t for a chat with a friend and an off the cuff comment about modern fuel, the bike probably would have been broken for bits and on ebay.

So in signing off I wish to say thank you to all those that have posted suggestions & helped me and please at any time feel free to take the P out of me as much as you wish as I really deserve it.
Wardy.

[oldzed]

Its always obvious once you know what it is.
We have probably all been there. I know I have , more than once.
Glad you got it sorted

[Wardy]

Ha Thanks Oldzed, makes me feel a tiny bit better........but still feel a proper Muppet.
Going for another test ride later, just to be sure to be sure.

Fingers crossed.

[Pigford]

Feckin' t**t

[zapo]

Ha Thanks Oldzed, makes me feel a tiny bit better........but still feel a proper Muppet.
Going for another test ride later, just to be sure to be sure.

Fingers crossed.

The important thing is that you bothered to give a concluding update witch a solution that we can all keep in mind for the future.

[TiBolts]

So it's been faulty since 2013 according to your original forum thread...

Glad it's sorted, but weird that at 70 mph when suffering from the problem at a steady speed, opening the throttle cured it, even though the filter was blocked. You'd think that would make it worse as it demanded more fuel.

[Wardy]

To conclude.
I've taking the bike on my normal ride to work route where i normally break down twice (each way) and a good 20 mile motorway sprint and all is fine.

Never ever overlook the bloody obvious.

Wardy