Which stick coils interchangeable between models

[Bendy toy]

My 2008 GSA has an intermittent missfire on the RHS cylinder. I'm sure it's that one because the exhaust pipe is cooler when it's running rough. The problem is worse when the engine is hot so I'm pretty sure it's a coil.

The engine seems ok at medium & higher revs and more open throttle. I sometimes get a 2 stroke style sound on overrun with light throttle. It can also bang loudly if I shut off but don't fully close the throttle. I'm thinking maybe unburnt fuel gets down the pipe.

I don't want to fit new coil(s) to find the problem is elsewhere. Does anyone have a spare centre head coil RHS?

If I buy used, will Mk1 coils (pre 2008) work in the Mk2?

 

[Pukmeister]

The coils were improved on the later bikes, with grey coil body ends instead of black. They still fail though.

The centre head coils are the same for both cylinders, it's the lower coils that are handed left or right due to the slight differences in angles. Can't you borrow a coil and do a test ride to prove?

You can also measure the primary and secondary resistance, be aware that there is some form of diode involved as you only get a measurement one way not both.

Could be worth changing spark plugs and doing a lambda trace with a GS911, plus reading for fault codes. I had a RH lambda heater fail with poor running.

 

[Bendy toy]

I'm humming & harring about getting a GS911.
Did some more useful Googling last night & found the low speed low throttle stepper motors could be an issue. It feels like a 2 stroke coming onto the pipe 4 stroking then smoothing out as it starts to fire every rev.
I've not yet had the secondary coils out. Later today I hope.

An aside has anyone tried a pair of mini coils with HT leads in place of the angled secondary coils. Placed out of the way they may be less vulnerable to corrosion and heat and might even be less costly.

It's an off the wall idea but maybe someone has tried it.

 

[hatzyian]

The lower coils can be interchanged, don't really fit 'correctly' but it can be done for troubleshooting.

 

[Bendy toy]

The plugs look clean and tan colour and the idle valves are also clean with the sleeve moving freely. I've struggled to get reliable resistance readings from the coils because my test meter prods are too short. I messed about with some insulated wire but still not reliable. But the plugs look good so sparks must be coming through.
TPS reset so on next ride I'll see how it goes.