H1 Electrics - Questions

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Chazzman_bm
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My Bike: ZXR400 H1
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H1 Electrics - Questions

Post by Chazzman_bm » Sun Oct 27, 2019 2:04 pm

So folks,

The old H1 is finally getting some love and I have spent the last couple of weekends in the garage. Along with the braking system, I have been trying to get the bike to run. It has been sitting for a while so it hasn't fired in over a year and hasn't been run in a lot longer than that. In any case, the last time it fired, I had to bypass the fuel pump relay to get fuel to the engine. I bought a second hand relay but it still doesn't so I've just ordered a brand new one from Kawasakioriginalparts. Fingers crossed that fixes the problem.

What it has done though is made me want to learn more about the H1's electrics so I am studying the diagram from Bannerman. Thanks for that! It takes away a LOT of the headache. I have a couple of questions though around some of the electrical bits on my bike.

1) As the H1 is a Jap import, is the CDI different than the UK models? Is it restricted in any way?
2) I have a red box at the front of the box with "PoshFirm" on it and I have no idea what it is for. Does anybody have a clue?

Thanks.

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banner001
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Re: H1 Electrics - Questions

Post by banner001 » Sun Oct 27, 2019 6:43 pm

1. All the h models are imports, none were ever officially sold over here so all the CDi are jap restricted.

2. That box will be a 180kph de restrictor box, it fools your CDi I to thinking you never go over that speed. If you are on mph clocks you need to keep it otherwise you will be limited to 10k rpm in every gear, if you have kph clocks you can leave it connected to go more than 180kph, or connect it back into the kph clocks to limit yourself to 180kph.

I would be tempted to say use my diagram, remove your old loom and make yourself a full replacement... No better way to learn than by doing a full loom...i can make one but will need to charge for time and materials.
Last edited by banner001 on Fri Jul 03, 2020 4:40 pm, edited 1 time in total.
UK ZXR400 L3 (1993) - Fully restored and on the roads, my green beast!
JPN ZXR250 A2 (1990) - Revs to 19,200rpm... 'nuff said :smt003

Chazzman_bm
Posts: 42
Joined: Sat Apr 22, 2006 2:43 pm
My Bike: ZXR400 H1
Location: Scotland

Re: H1 Electrics - Questions

Post by Chazzman_bm » Sat Nov 02, 2019 1:38 pm

Thanks for answering my questions Bannerman. I am indeed tempted to make a new loom myself but it seems like an incredibly daunting task. I am all for giving it a go but my first question is where do I get the replacement (correctly colour-coded) wiring and new connectors? ....or would it be safe enough to reuse the old connectors?

There is also the issue of testing the 30 year old components. Given your information about the CDI, I would be more inclined to ditch the H version in favour of an L model with a new loom. .....and the old coils for stick ones. Murray1992 suggested they would give better performance and better starting so that's tempting as well.

Ok, I seem to have talked myself into making a new loom. Have you got a preferred supplier for the wires, connectors, etc?

Thanks.
Chazz.

Chazzman_bm
Posts: 42
Joined: Sat Apr 22, 2006 2:43 pm
My Bike: ZXR400 H1
Location: Scotland

Re: H1 Electrics - Questions

Post by Chazzman_bm » Sat Nov 02, 2019 6:57 pm

I have been reading up on the CDIs available for the different model ZXRs and It's still clear as mud. Although I think replacing the old loom with a new one is a very good idea, I also believe that my CDI unit is faulty so I want to replace it as well. Ideally, I want to get rid of the top speed restriction of the H1 CDI and also get rid of the PoshFirm de-restriction unit attached to my speedo unit. In my mind, having less electrical devices in the signal chain is more efficient and cleaner.

Unfortunately, it's not as simple as I hoped and there are other electrical considerations with things like the speedo (mph vs kph), timing rotors, etc. Another post on here suggests that the blue CDIs (UK models) offer the most power but will not work with the Japanese H model ZXs, i.e. mine.

Now back to my idea of building a new and custom loom. Someone said the blue CDI wouldn't work because it had different circuitry than the red one (I can't remember what that was exactly). If I wanted to use a UK spec blue CDI unit with UK speedo, what other mods would I need to do?

Cheers guys.

Chazzman_bm
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Joined: Sat Apr 22, 2006 2:43 pm
My Bike: ZXR400 H1
Location: Scotland

Re: H1 Electrics - Questions

Post by Chazzman_bm » Fri Jul 03, 2020 12:00 pm

I made the decision to make a new wiring loom for the old H1 and finally pulled the loom out to inspect it. As you can see from the pictures, it's not in great shape, so it absolutely needs some attention. I've never done this before so I fingers crossed I don't F it up. Mind you, it's already fecked so I've got nothing to worry about. :smt003
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banner001
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Re: H1 Electrics - Questions

Post by banner001 » Fri Jul 03, 2020 4:53 pm

Sorry, i must have missed most of the questions on here:

Wiring i go for Vehicle Wiring Products (more expensive) or Kojaycat (cheaper but stock can be an issue), connectors you can get generic ones from either supplier too, some you will only be able to get from Kojaycat and some you cannot get at all so bear this in mind.

You can swap CDi but you need to L Pickup rotor as well, personally i would stick with the H1 and just keep your de-restrictor box.

Stick coils are a personal preference, personally having tried them im not a fan, i might just have had bad sticks/plugs or fuelling, but when i tried some i was not a fan.

I would recommend getting a proper wire stripping tool (i.e. https://www.amazon.co.uk/STANLEY-FATMAX ... B00CD24EAK) as it makes that bit a breeze, use only non-insulated connectors, get a proper crimping tool for non insulated connectors and get cracking!

If you do decide to use a blue M CDi, L pickup rotor and mph clocks then all the wiring is the same, you just dont need the pink wire. THe actual positions of the wires onto the CDi though are probably different. I dont have a H1 bike so i cant tell you what wires go to what pins, but if you look at yours, work out what them wires are going to, then ask me what my 1993 L modesl pin outs are i can tell you, you just then swap your "H" colours into my "L" CDi pin out.

As for the derestriction you will still need to "keep the poshfirm box" as you need to fool your CDi into thinking you have the clocks attached and are under 180kph. Though if you make the loom yourself that poshfirm box can be located under the seat, or tail unit etc... or you just swap it for one of RedExRob's resistor mods that he talks about as that is all the box is doing. Or you get a kph to mph speedo convertor and leave your clocks connected into the loom - this is what i am doing on my zxr250r.

If you are UK located i can always come round one weekend to give you a hand if needed
UK ZXR400 L3 (1993) - Fully restored and on the roads, my green beast!
JPN ZXR250 A2 (1990) - Revs to 19,200rpm... 'nuff said :smt003

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banner001
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Re: H1 Electrics - Questions

Post by banner001 » Fri Jul 03, 2020 4:57 pm

ah scotland...well i get 55mpg on the motorways and am in the midlands, so if you need me to come up for a weekend your looking at ~£70 for us to come visit in fuel costs, and if you can provide neeps, tatties, haggis and some good Islay's i might lower the charge :D
UK ZXR400 L3 (1993) - Fully restored and on the roads, my green beast!
JPN ZXR250 A2 (1990) - Revs to 19,200rpm... 'nuff said :smt003

Chazzman_bm
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My Bike: ZXR400 H1
Location: Scotland

Re: H1 Electrics - Questions

Post by Chazzman_bm » Sat Jul 04, 2020 11:06 am

Hey Bannerman. Yeah, Scotland's not quite around the corner from you so I appreciate the offer but I'll spare you the trip. :smt001 I have removed all the tape, make my cable jig and labeled everything up so I think I'm in good shape for making the new one. My early thoughts were that a lot of the electrical components were faulty which is why I considered replacing so many things (CDI etc). I'll make the new loom with connectors and see what happens from there.

One of the biggest reasons for tackling this project is to learn motorcycle electrics. It's something that has intimidated me but as I work my way through this, I'm learning quite a lot and feeling pretty good about it all.

Thanks for the tips and help so far. I'm in the process of putting my shopping list together for Koyacat. I'll take some pics and post then up as I go along.

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banner001
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Re: H1 Electrics - Questions

Post by banner001 » Sat Jul 04, 2020 6:04 pm

Motorcycle electrics from the 70's up to the mid 2000's dont really change.

Before then you have 6V things, and points ignition, but from then onwards they get generic.

Learn the circuits first, so ignition, charging and reg rec.

Then move onto starter lockouts.

Then lighting, then ancillary connections... And that's it!

Every bike you work on will be basically the same if you can learn the basics of the above circuits
UK ZXR400 L3 (1993) - Fully restored and on the roads, my green beast!
JPN ZXR250 A2 (1990) - Revs to 19,200rpm... 'nuff said :smt003

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