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Discussion Starter #1
Hi guys, can I ask for some advice about rough cruising?
I bought the bike a couple of months ago, R1 2011.
The shop was near Manchester and I live in Bristol so it was a bit of a ride home.
After an hour or so I began to notice some roughness/suddenness when opening from a closed throttle.
'Maybe the chain is a bit loose' I thought.
As time went on it got worse and worse, until it was difficult to cruise due to the engine apparently cutting in and out a couple of times a second.
This made it quite dangerous trying to get round roundabouts!
Opening the throttle a bit further made everything go away, but that is a difficult thing to do in heavy traffic...

So, I sent it back to the dealer. They ran it on a dyno and said it was fine (insert $rant about stupid dealer not listening here...)

Eventually they sent it back and it was the same, pretty much ok when cold, but getting dangerous over a long ride.
After further discussions they asked me to change the spark plugs - no point sending it back to them.

On removing the tank I see that the fuel pipe is a bit kinked, so I am now waiting for parts to do the fuel pipe mod.
I am thinking I may replace the spark plugs as well, anyway.

I also got into diagnostic mode, thinking the TPS might be faulty. This is where some advice would be appreciated.
The numbers on the display seem normal, well within range at closed throttle and increasing linearly with throttle opening.
But I noticed that just off idle there is a buzzing noise and something seems to be fighting me. I can't open the throttle smoothly.
I assume it is something to do with the Throttle Servo Motor.
Looking at the workshop manual, as far as I can see the throttle cables only move the TPS, there shouldn't be anything else connected to my hand.
So what is making it stiff? The buzzing noise goes away at (I reckon) the same throttle setting that smooths the engine out when it is running, and from there on the throttle is easy to move.

Does this sound right? Any info appreciated.
 

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Discussion Starter #3
Further progress over the weekend.

It seems my questions about the TPS were a red herring.
The 'graunchiness' was due to the fact that there is a spring between the throttle cables and the end of the throttle butterfly shaft.It seems that at low throttle openings the shaft is vibrating. I assume some wear/ free play is causing feedback between the motor and the position sensor.

Below are two videos, the first is from a couple of years ago, from someone who had the same problem as me:


As you can see the throttles should not be doing that.
The second is my throttles.


At the moment my plan is to change the spark plugs and do the fuel mod. I do not expect this to fix the problem now!
 

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Discussion Starter #5
Sorry, but I don't think this is the same issue. Anyway, the shop I got it from have agreed that the throttle bodies are borked and are sending me a new set. Further updates to follow!
 

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I had a similar problem. I thought it was the TPS since that was an issue with the 2004 and newer R1's. Took it to the dealer and it was the plugs. Replaced them and the bike has been running better than ever!!
 
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