Author Topic: Wiring 2RH CDI into 4FL  (Read 1078 times)

solomonheckler

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Wiring 2RH CDI into 4FL
« on: November 13, 2019, 08:17:49 PM »
Hi all.

I saw an article a while ago showing the 4FL ignition curve VS other TZR models and I wondered is swapping out a CDI from a 2RH in to my 4FL would give any gains. I looked at each wiring diagram and it seems that the 2RH has a seperate YPVS control unit whereas the 4FL has this built into the CDI (I think).

Is it possible to use the 2RH CDI on my 4FL and if so does anyone have any experience or advice on how I should go about it.

Thanks
« Last Edit: November 13, 2019, 09:07:12 PM by solomonheckler »
1987 CBR250R Hurricane
1995 TZR 125 4FL Japan Model
1991 KR1-S 250
and a few mountain bikes

Martin77

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Re: Wiring 2RH CDI into 4FL
« Reply #1 on: November 13, 2019, 09:55:23 PM »
I'm not sure if it'd work, and even then I doubt you'd gain power if any. The 4FL curve already has more ignition advance, apart from the dip from 5-7000, which is below the powerband anyway. The 4FL has the pv controller inside the servo doesn't it? (three wires going to the servo means it is internal)

You would be better with a Zeel or ignitec which can be tweaked to be spot on.

41juergen

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Re: Wiring 2RH CDI into 4FL
« Reply #2 on: November 14, 2019, 08:05:03 AM »
Agree with Martin, did that for a friends bike. Unfortunately at that time the PV was still restricted but the Zeel gave a 2 HP higher topend. And as Martin said, down between 5-7 k rpm there is now significant change based on any ignition timing mod.

solomonheckler

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Re: Wiring 2RH CDI into 4FL
« Reply #3 on: November 14, 2019, 09:21:06 AM »
Thanks for steering me away from a complicated and pointless mod.

Many thanks fellas.

G
1987 CBR250R Hurricane
1995 TZR 125 4FL Japan Model
1991 KR1-S 250
and a few mountain bikes