Knock Knock

DrogoNevets

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...no this isnt a knock knock joke

so let me tell you a little story,
was driving from wiltshire-surrey on saturday, and noticed i was low on fuel, so i pulled off the a303 to go to a petrol station. After a 1 or 2 mile "spirited" blast (nothing to excessive but certainly, i wasnt hanging about) i notice the engine started running REALLY rough and uneven.

Thinking this was due to the fuel being low (it was very low) i thought not alot of it. This was until i filled up and it continued and cut out.

Thinking it could be that fuel hadnt worked its way through the system yet i leave it for the period of a coffee. Start it, and its the same.

After a finishing my trip to surrey (was vital i got there) it seems alright. Ran it from Surrey to Devon this morning and it's back.

So the full list of symtomns is
uneven running of engine (make bike vibe quite badly)
popping/barking coming from the exhaust regularly
decreased MPG (i noticed, but this could be coincidental)
knocking coming from somewhere on idle
not able to hold steady revs whether it be at idle or with a bit of throttle on.

She is well over due a service, which i have booked her in for now, oil is fine.

Open to suggestions - knocking sounds like its coming from the rear/behind the engine, but my hearing is pretty shot so not completely sure on this one
 
i mean the quantity of oil is fine
it is due a change, but wouldnt expect to hear knocking from old oil (would you?)

ive booked it into gsshop (on reccomendation from a mate) who rekoned similar (plugs, oil, lambda, etc) and as its coming up to its 24k service which replaces 99% of the obvious suggestions he's just going to do that, and see if it fixes it, if not, let the fun times begin!
 
DrogoNevets said:
i mean the quantity of oil is fine
it is due a change, but wouldnt expect to hear knocking from old oil (would you?)

ive booked it into gsshop (on reccomendation from a mate) who rekoned similar (plugs, oil, lambda, etc) and as its coming up to its 24k service which replaces 99% of the obvious suggestions he's just going to do that, and see if it fixes it, if not, let the fun times begin!
Click to expand...

A long shot I know but I recently had problems with a cylinder cutting in and out leading to very rough running etc. Turned out the throttle valve connector was half full with water which explained why the problem was noticable under heavy braking or going downhill. The pins had started to corrode as well so it must have been an issue building up over time and gradually getting worse. Worth taking the connectors off on the throttle bodies and check their condition etc - can't do any harm.
 
New info on the above
the knocking i beleive is coming from the right cylinder
you can feel it on the big black pipe (air intake?) going into the cylinder when it knocks

also if you lick you fingers and touch left down pipe its warm but not too hot, do it to the other side and it is scorching hot (even after licking fingers it hurts ;))

am I right in assuming that it sounds as if the right cylinder is back/misfiring and that is causing the knocking? suggesting blown spark plug maybe? (i really dont know anything about engines so could be wildly wrong, open to more expert opinions)
 
for what they cost change the plugs first ,thats the cheepest option.
always start with the most ovious and cheepest:thumb
 
Coilpack, when you say should be picked up...replaced as per service schedule (which is the 24k service) or noticed with a phone call saying ill need more money??

Somare we in agreement from what i have described, that spark system (whether coil pack or plug) is the most obvious issue here??

If so what causes these to fail??
 
Pull the coils...

You can pull the coil packs and see if the metal casings have split..

I had a secondary fail ( the one on the underside plug) and it was obviously split open and rusty..

You can even swap coils left to right to see if the Problem moves sides. Someone will say that the secondary coils are handed, left to right, it's true but for a short time thy will fit fine..

If the problem moves to the left with the coil stick swap, move the secondary coils back again leaving the mains swapped... That shouldd ID the rogue oil stick for you.

Mr BMW will then take cash from you for a new coil. £80 a go I seem to recall.

Roger.
 
Easier said than done when you are in a strange town (Exeter if anyone around to lend a hand) and living in a hotel with no tollbox (one issue of the adventure over the standard gs is the bash plates will need removing)

But sounds like a plan to try if i can find someone willing to give us a hand

Cheers
 
it's easy to disconnect the lead fitting on to the coils using a small screw driver or knife. Disconnect one side main coil with the engine running. the engine tone should change very slightly. if not then it could be that coil. if the engine tone changes dramatically to run rough as dogs then it would point to the secondary coil on that side.
 
Tools!

You'll need to remove the plastic covers over the secondary coils... Torx bit.

If its a GSA removing rocker cover guards... Again torx..

Plug covers and coil sticks are a pull off job or assisted with a screwdriver..

Sump guard stays where it is. Nothing else needs removing..

Being close on 200 miles away I can't assist, sorry.

Roger
 
DrogoNevets said:
also if you lick you fingers and touch left down pipe its warm but not too hot, do it to the other side and it is scorching hot (even after licking fingers it hurts ;))
Click to expand...

By "down pipe" do you mean the exhaust ? I'd say that touching the exhaust headers under any circumstances is a bit unadvisable unless you want to risk losing your fingertips !
 
yes i meant the exhaust pipes
i tapped the cylinder head and the right one felt alot colder than a thought

and by touching i mean tapped

it wouldve burnt had i of lef tmy fingers there for 2 or 3 seconds, but the left burnt straight away prooving (to me) that the right cylinder isnt firing as often as it should be. I may of managed to source some torx bits to remove rocker guard, so will see if i can prize the coils

am i right in thinking, that if i pull the poils off and nothing changes at all, we have found the issue?
 
Ok people, help me out here

just removed the rocker cover (why did no one remind me i have a small tool set under the seat?!) and here is what happens

remove secondary (under the cylinder) oil and popping all buts stops, remove primary (side of cylinder) and nothing changes

removes both and she runs pretty rough, but arguablly better than she did

am i right in thinking that this means its the coil and/or the plugs?
 
when you remove the primary coil there should be a slight, and i mean really slight, change in engine tone. i assume that if there isnt a change then that would point to the primary coil/spark plug not doing much.
 
Its more a case of runinng normally it sound horrid

Take out secondry coil and the knocking/backfiring virtually completely disappears (not a fan idling still but i assume thats to be expected?) hence my think more secondary than primary?
 
Nippy Normans supply Touratech, Wunderlich, Desert Fox and many other makes of accessories.
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