MK2 / ST Ignition running on a 900 n Coil Woe's ......!

[johny brando]

Doe's any one have for sale ......a pair of decent MK2 /ST1000 coils ? Also the Factory part number from these coils, or happens to know if any other machine shares the exact same coils ?
Now, I'm running MK2 ignition on my 900 & for the last 7000 miles it's been absolutely fine , but now I'm getting a intermittent
hunting at a steady 4000rpm's & seems like it's dropping 1 & sometimes 2 cylinders this, when it gets up to normal running temp & it feels almost the same as ....when your just running out of fuel (checked & definitely NOT a fuel issue ) Now, I confess to not being that electrically savvy but I sort of get by OK. I fitted this system inc the I.C. Ignitor, Pick Up's coil & the protecting remote - Coil Resistor many years ago & BUT I never used the MK2 coils ...thinking they were exactly the same ! (& now when checking out the Ignition system with a meter & manual I find there NOT ! ) they have a much lower primary & secondary Ohms resistance ..........so maybe my existing coils are now starting to break down at lowish rev's (apparently the the MK 2 coils runs a very low resistance primary winding to give a better spark @ high rev's & the coils are protected from low rev range burn out by the remote coil resistor. Now all the MK2 ignition seems (by meter & manual ) to check out 100% also timing & A/Retard unit fine too ....yet my 900 coils (meter leads in each coil HT lead end ......seem to be showing about 14000 ohms & the manual stated 30000 Ohms ) which leads me think there on the way out ....yet next time I rode it ...it was fine again & no hunting !!! ( I did however then change out for new ......all the spark plugs ......that was done at the same time as when I was doing the testing of all the Ignition components )
So if you can help out with any S/Hand MK2 / ST coils , & any relevant donor info etc well, I'd be grateful of your support. Thanks guy's. Johny Brando.

[Taffus]

if you are running an "IC Igniter" then dyna grey coils are the way to go.
The green coils are 3 ohm, grey are 2 ohm. This is the dynamic impedance of the coil, think of it like water pipes but the lower the number the bigger the pipe.

The standard stuff looks very similar to each other, maybe someone can tell you.
Here are the other bikes with the same coils

[johny brando]

if you are running an "IC Igniter" then dyna grey coils are the way to go.
The green coils are 3 ohm, grey are 2 ohm. This is the dynamic impedance of the coil, think of it like water pipes but the lower the number the bigger the pipe.

The standard stuff looks very similar to each other, maybe someone can tell you.
Here are the other bikes with the same coils

THANKS TAFFUS. REALLY APPRECIATE YOUR KIND N QUICK REPLY & GREAT INFO ! I'LL BEAR THAT IN MIND BUT BECAUSE I'VE STRENGTHENED MY FRAME THERE ,THEN THEY MAY NOT FIT IF THERE AT ALL PHYSICALLY BIGGER . SO GENUINE 1.5 OHM COILS IS MY PREFERRED CHOICE IF AT ALL POSSIBLE. I'LL CERTAINLY PUT THAT IN THE MEMORY BANK THOUGH ! CHEERS BUDDY.

[KWACKERZ1]

I believe a lot of Yamahas r1 thundercat have 2 ohm coils.

[johny brando]

Doe's any one have for sale ......a pair of decent MK2 /ST1000 coils ? Also the Factory part number from these coils, or happens to know if any other machine shares the exact same coils ?
Now, I'm running MK2 ignition on my 900 & for the last 7000 miles it's been absolutely fine , but now I'm getting a intermittent
hunting at a steady 4000rpm's & seems like it's dropping 1 & sometimes 2 cylinders this, when it gets up to normal running temp & it feels almost the same as ....when your just running out of fuel (checked & definitely NOT a fuel issue ) Now, I confess to not being that electrically savvy but I sort of get by OK. I fitted this system inc the I.C. Ignitor, Pick Up's coil & the protecting remote - Coil Resistor many years ago & BUT I never used the MK2 coils ...thinking they were exactly the same ! (& now when checking out the Ignition system with a meter & manual I find there NOT ! ) they have a much lower primary & secondary Ohms resistance ..........so maybe my existing coils are now starting to break down at lowish rev's (apparently the the MK 2 coils runs a very low resistance primary winding to give a better spark @ high rev's & the coils are protected from low rev range burn out by the remote coil resistor. Now all the MK2 ignition seems (by meter & manual ) to check out 100% also timing & A/Retard unit fine too ....yet my 900 coils (meter leads in each coil HT lead end ......seem to be showing about 14000 ohms & the manual stated 30000 Ohms ) which leads me think there on the way out ....yet next time I rode it ...it was fine again & no hunting !!! ( I did however then change out for new ......all the spark plugs ......that was done at the same time as when I was doing the testing of all the Ignition components )
So if you can help out with any S/Hand MK2 / ST coils , & any relevant donor info etc well, I'd be grateful of your support. Thanks guy's. Johny Brando.

ALL STOP ON EVERYTHING !...... Up-date...... Since the post above I've managed do about 150 smiles on it & it seems fine now ! Not a hunt or misfire "YET" ( I shouldn't speak too soon = The kiss of death ! ) It now appears to be likely either ..... A Spark plug going south (...which apparently cause's the other plug on that coil to join in & break down too . OR ..... & I failed to mention this (....trying to keep some dignity ! ) when I built the bike decades ago I failed to remove the Stove Enamelling at the coil mount points which could have = a poor coil earth .....this I noticed when I ripped the coils off to check them & the coil resistor out, so at that same time I got my Drebal out & righted that wrong ...but kept that to myself Oooops ! So just maybe / hopefully all will remain alright . Cheers, Johny B -Good