Ignition Coil Help/Advice Needed

[Paranoid]

My '06 R1 with just under 31K miles started running like crap yesterday. It sounded like a V-twin, smelled rich, bogged under 5K RPM when hard on throttle. (It starts up without hesitation and when it's warm, it uniformly drops in RPM but at idle and accelerating from stopped sounds like a twin)



I pulled the spark plugs last night (photo at bottom). They are original stock CR9EK plugs with ~31K miles on them and they look fine. I went ahead and bought new plugs today since they're way overdue.

{Please don't flame me for being lazy on maintenance. I know plugs are supposed to be changed every 8K, and I'm overdue for valve check, yada yada.}

Maybe I was a bit premature in pulling plugs. Should I have checked for spark first? (I can easily reconnect to coils and do the "ground on motor" check). But since the plugs look fine I was thinking that it is more likely an ignition coil problem (or something worse??). But I'm not a mechanic so I figured I'd ask the R1 geniuses on this board.

I just tested the resistance:

Primary Coil Resistance spec is 1.19 - 1.61 Ohms per the Service Manual.
All of mine were at 1.8 Ohms. Is it OK to have higher resistance, just not LOWER? i.e. Do I need to replace all FOUR coils?

Secondary Coil Resistance spec is 8.5 - 11.5 K-Ohms
Mine:
#1 = 9.60
#2 = 8.35
#3 = 9.64
#4 = 9.71

I'm thinking the #2 ignition coil is providing a weak spark but I don't really know what I'm talking about. Can any of you confirm this?

In short, do these numbers indicate I need FOUR new coils or just ONE (or none)? If none, what do you think the problem is?

Thanks in advance for any help.



my stock NGK CR9EK plugs after 31k miles

[BSR-1]

I'd just put the new plugs in it first before getting all carried away tracing electrical circuits.

just remember, check the cheapest/easiest stuff first & 90% of the time you'll find your problem.

[Paranoid]

I put the new plugs in. Good news is my bike no longer sounds like a V-twin. I rode it around the block and it doesn't bog down under hard acceleration.

Bad news is, I have an erratic idle now. I set the idle at 1100'ish and it randomly jumps to 1300 or so (like one cyclinder is getting more gas or something??). I thought maybe I pinched a wire (?) near the idle screw when I put the front sprocket cover on after doing the 520 conversion a few days ago. So I took the sprocket cover off and wiggled those hoses and wires while the bike was idling. Still randomly erratic no matter where I held the wires/hoses. I played with the idle adjuster screw and adjusted EXUP cable tension. Still erratic. I'll admit the idle might have been a little rough before the whole "V-twin" issue but it wasn't THIS jumpy.

Any suggestions are appreciated.

When I have more time I'll investigate the idling issue and double check my spark plug install (how sensitive are spark plugs to "proper" torque value?? I just screwed them in hand tight and then a smidgen more). I'm thinking the problem is electrical but I'm not sure where to even start looking.

I'm just glad it runs reasonably well so I can get to school/work.

Thanks to everyone that replied.

By the way, putting the mid-fairings back on was SUCH A PITA!!!!! and the last radiator bolt too

[BSR-1]

glad to hear it's running!

about the idle, what's your air filter like?

[Paranoid]

oh sheet.

yeah....my (stock) air filter....it's probably dirty as heyull. I haven't cleaned it or replaced it since I bought the bike new (Christmas 2005).
So, yeah, my air filter's got ~31K miles of debris in it.

Service manual says check every 4K miles...uhhhh...I'll get right on it...

[THECLAYTON]

Did you Gap all of the spark plugs?

[THECLAYTON]

Also, I didn't think they came stock with EK plugs. I thought they came with single electrode stock?

[BSR-1]

Originally Posted by THECLAYTON

Also, I didn't think they came stock with EK plugs. I thought they came with single electrode stock?

EK=stock

[Paranoid]

Just an update in case someone is searching.

IT WAS THE IGNITION COIL!!! (the #2 coil)

The UPS guy dropped off my new OEM part today. (A big thanks goes out to Ron Ayers for selling this part at half of what my local shop wants to charge me.) I plugged it in and started up my bike and it sounded normal for the first time since August 5th.

On August 5th, the #2 coil resistances were 1.8 Ohms for primary and 8.42 k-Ohms for secondary (then 8.35 a while later). Secondary should be between 8.5 - 11.5. Even though it was just BARELY below spec, the low resistance WAS IN FACT an indicator that this coil was going bad. I tested the #2 coil today and the secondary was down at 8.09 k-Ohms. I have been riding it every day even though it was probably ill advised. The stuttering and missing definitely got worse, which was reflected in the resistance reading today.

As a sidenote, the service manual states the primary coil resistance should be between 1.19 to 1.61 Ohms. All of mine were consistently at 1.8 Ohms. My bike runs fine. If your SECONDARY resistances are a little low, then that is the likely the problem.

Hope this helps someone down the road.

(By the way, it helps if you take a Sharpie and label your coils on the clear/yellowish plastic top part just to prevent any confusion)

[GhostfaceninjaT]

Thanks Paranoid for an extremely helpful thread!!!

[RideSlow]

I have the exact same problem with my bike and this thread just saved me a ton of money getting it checked out

[batman007]

ok so i have the same problem,, i changed my spark plugs last week,, and i still have the same issues, misfiring after the bike is warmed up... sounds like a v twin at times until i get to over 4k rpm, and probably running on less than 3 cylinders at times, very weak engine power under 4k rpm,

so after reading this thread i presumed it was one of my coils,,so before i go out and buy some coils on ebay, i went out and bought a voltimeter to figure out which coil or coils are bad so i can replace them, all 4 coils seems to be good. 1.4 ohm on all, and about 9.41-9.45 on all 4 coils... i am totally lost now.. can anyone point me in any other direction or what i could diagnose next??


2005 r1 with 47k miles... seemed to be running fine and all of a sudden a few weeks ago, it sounded like a vtwin and loss of power near idle.. but runs perfect after 4k rpm. replaced the plugs with stock ngk ek plugs and still have the issue after the bike gets warmed up. please help anyone

[BSR-1]

Originally Posted by batman007

ok so i have the same problem,, i changed my spark plugs last week,, and i still have the same issues, misfiring after the bike is warmed up... sounds like a v twin at times until i get to over 4k rpm, and probably running on less than 3 cylinders at times, very weak engine power under 4k rpm,

so after reading this thread i presumed it was one of my coils,,so before i go out and buy some coils on ebay, i went out and bought a voltimeter to figure out which coil or coils are bad so i can replace them, all 4 coils seems to be good. 1.4 ohm on all, and about 9.41-9.45 on all 4 coils... i am totally lost now.. can anyone point me in any other direction or what i could diagnose next??


2005 r1 with 47k miles... seemed to be running fine and all of a sudden a few weeks ago, it sounded like a vtwin and loss of power near idle.. but runs perfect after 4k rpm. replaced the plugs with stock ngk ek plugs and still have the issue after the bike gets warmed up. please help anyone

Do you still have the stock EXUP valve?

[batman007]

i really have no idea, the guy said the bike was all stock except for the ohlins dampner.

should the EXUP valve be removed? or what are you getting at?

[Slvr04r1]

Any suggestions are appreciated.

I had the same exact issue and it was a bad coil, it wasent totally shot but i was cracked and arching, got a used one for 10 buck prob fixxed

[Slvr04r1]

replace the dam coils with some used ones and see if that fixes it.... this happes more often then you think ive had it happen 3 times on 3 diff bikes

[Slvr04r1]

lol glad its fixed just read the whole thread

[batman007]

i dont mind replacing the coils, but mine look like and they are perfect and all the resistance in all of them are in spec and nearly identical, if i could just find one indication of a bad coil i would replace it, but the volt meter could not help me.

[BSR-1]

Originally Posted by batman007

i really have no idea, the guy said the bike was all stock except for the ohlins dampner.

should the EXUP valve be removed? or what are you getting at?

After a lot of miles it can get stuck or the cables can get out of adjustment.

Check it out for proper operation, when you turn on the key it should cycle fully open/closed.

[batman007]

it opens and closes when key is turned.