Lumpy mid range: 1150 Adv

[Repoman]

Just had my Adv back from a service at Williams in Manchester hoping they would cure the mid range problem I have.

The bike seems to not pull crisply and generally just feels a bit sluggish. Previously I thought this was down to throttle body Balancing (?) as Duffys in Ireland had diagnosed this a couple of years ago and it seemed to fix it, as did a new coil.

Williams diagnosis is that one of the stick(?) coils was badly corroded and that the baffle in the Remus had collapsed, both contributing to the problem.

So advice please:

Is the coil replacement an easy job? I think they quoted about £55 for the part and £25 for the labour so presumably it's a 5 minute job

Why would a corroded coil cause the problem. Isnt it either working or not?

What's the story with the Remus? Can you replace the baffle, if so where do you get one and how do you do it? I was very surprised at this the can doesnt sound any different, just the usual low drone of a thousand bomber raid....

I'm reluctant to give Williams any more dosh as I think £350 for the major service (plus rear pads) was damn steep.

Any diy advice appreciated. Thank you kindly.

 

[John Armstrong]

IIRC when the spark is made it's due to the field collapsing and this induces the high voltage that the spark plug gets. So if the coil is corroded or damaged this will interfere with the electrons trying to run away. Effectively the coils capacitance has been increased / decreased and this will affect the timing of the spark.

I think. I'd guess it'll have most effect when you're trying to get most power out of the engine as then timing of the spark will be at its most critical.

 

[Repoman]

right....right....

er, can I just go back and do my physics O level again, wont be a minute...

Thanks John: any other comments re fitting?

 

[Steptoe]

Is the coil replacement an easy job? I think they quoted about £55 for the part and £25 for the labour so presumably it's a 5 minute job

.

The twin spark main coil is in the spark plug cap . So replacement takes 2 minutes.
It's a very common problem on twin spark biles.

 

[Repoman]

Cheers Steptoe: I'll have a poke about

Any one any ideas on the Remus baffle question?

 

[John Armstrong]

Cheers Steptoe: I'll have a poke about

Any one any ideas on the Remus baffle question?

Try fitting the BM one back on and see what happens? Assuming that you've still got it and didn't have to butcher the y-piece / cat to get it to fit

 

[cookie]

will have to have collapsed a lot to be more restrictive than bmw oem item

take it off & have a look at it. sounds like BS.

 

[Steve101]

I'm with Steptoe. I had a real lump / pregnant pause when i cracked the throttle open for a bit of juice or an overtake.

It turned out to be the potentiometer. CW's replaced it with one off the shelf and that was defective too. The second one they put on worked fine. One of those black box magic electric things seem to be a little unpredictive!

They also replaced to coils, this is a 5 min job, once done she ran like never before!

 

[tinker-27]

remus

try calsport in birmingham for your remus parts they stock all remus exhaust parts you can contact them on 0121 753 0415

 

[Bigfish1978]

I had both stick coils in mine go in quick succession. One was a dead give away when the left hand one started creating a burning plastic smoke screen, the other was only discovered when speeds of 80-90 became really lumpy and it made the bike stutter like Arkright in Open All Hours ! - Got the bits from Motoworks and took 2 minutes to fit.