The primary resistance on my FZR400 coils is 1.8 to 2.2 (service manual), so 0.9 to 1.1 needed for COP's not many in that range.
You can use COP'S with a higher primary resistance, up to 3 Ohm's (wired in series) or a touch more, They will draw less current through your TCI and it'll last longer too
I made a note in my cheat sheets that the Denso 129700-5350 COPs are meant to be 1.1 Ohms. They're from a Kawasaki ER6. https://tinyurl.com/yymfv6gd
Thanks Frank, you are a scholar and a gentleman. https://coilspec.com/coilspec-ignition-coil-698622-kawasaki-4-pack/
Spec's i found for them were 1.1 Ohm's to 1.5 Ohm's on the first page here. You won't notice any difference in spark if they are 1.5 Ohm primary each
zx9r coils work beautifully Made a little sub harness with connectors from jaydee and spliced the 2 positives together to use a 3 pin connector for the sub harness to the original harness. Starts up so much easier and runs very nicely. View attachment 47414 View attachment 47415
Update on the new setup. Tacho gets a bit funky around 7 to 8000 rpm. Jumps around a bit if holding steady at those revs. Makes more power because my clutch is now slipping
Finally got my ZX14 COP’s and subloom delivered. Also got the “proposed” connector and pigtail leads delivered. Time to assemble! But wait! There’s more! Can anyone confirm if the wiring in the pic will work? Yellow boxed contents are from the donor bike. Red boxed contents is my proposed connection to ZXR original primary leads.
You need to check the primary resistance of the original coils on the ZXR250. If these are 3 ohms or so then probably best to connect COP 1 & 4 in series and 2 & 3 in series then wire each assembly to the standard loom, rather than a parralel connection as you have suggested. A number of other members have made this conversion and I am sure they will comment. Peter.
Cheers jmw76 Just back probed the primary’s between red wire and any other dashed wire. Measured 1.4 ohm. Should be approx. double that, according to OEM spec. Think that I got bad info from WWW N.B. Seen much good info on 2fifty site, reguards series configurations between 1&4, 2&3 but was trying to avoid chopping up subloom. Believe that this is the desired configuration.
If you want to try and avoid chopping up the loom, figure out how to remove the pins from the plugs themselves, or you may be able to get just the crimp pins for the plugs if any need to be re-pinned shorter - redoing the pins at either end is feasible, avoids cutting & soldering & taping
OK, I know this will end in tears if I force it, so does anyone know how to remove the yellow locking wedge?
Very likely a jewellers screwdriver in from the back - you'll be looking for a locking tab that lifts up when the yellow piece is inserted From the diagram it doesn't look like there's a locking tab on the top, BUT that depends if it's 100% accurate
129700-3881 i just got a pair of these, resistance test primary 1.0 ohm, not 2.5-3.1 Ohm primary as listed.
For which bike? Here's some details which specs them out at 0.8-1.2 https://forums.pelicanparts.com/7096463-post5.html So from that if you wire them in series, you should have a working resistance of about 2 OHM which is likely acceptable an close to your OEM coil resistance, but I see you got two, not four, so if they're going onto a twin that resistance may be too low and will overload the transistors
what ? you expect every detail posted on this forum to be 100% accurate? who the fuk are you anyway? go do your own bloody research!
I was just saying what the primary resistance was and that the original post on those coils was incorrect. But aye you wanna be like that. Go **** yourself.
So I have a set of Denso 129700-4840 COPs I realise 129700-5430 are recommended for the ZXR250 Can one of the white mans magic experts tell me why I cant/can use what I have 129700-4840 1.6 - 1.7 Ohm's primary around 13K Ohm's secondary Length 142mm 129700-5430, 1.1 Ohm's to 1.5 Ohm's Primary, 10.8 K Ohm's to 16.2 K Ohm's Secondary They are long enough