Upgrade for Kokusan on my Gt 550

All to do with wiring, charging or just trying to figure out whats gone wrong.

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saratoga
Still in the Driveway
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Joined: Wed Oct 03, 2012 2:20 am
Country: Finland
Suzuki 2-Strokes: GT 550, FZX750

Upgrade for Kokusan on my Gt 550

Post by saratoga »

Good evening all,

I'm new to this forum and my first question is does the 280 W Nippon Denso stator fit as a direct stator replacement for the Kokusan? And is the stator the only thing i have to change?
I stumbled over my old GT 550 cafe racer in the garage very recently. It has been standing there since the early nineties untouched. I got inspired as i got my hands on some really powerful cylinders, heads, fuel injection rods etc. Over 100 hp already in stock form. :twisted: And it looks like the package fits the old Suz block. (only minor machining needed) Will post some pics on the tuning side when i start having all hardware and can start the project. The old GT 550 is in for a huge conversion but I am in desperate need for more el power.
Any other good suggestions?

smoky regs

thomas
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jabcb
Moto GP
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Suzuki 2-Strokes: 69 T350 thru 75 GT750
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Re: Upgrade for Kokusan on my Gt 550

Post by jabcb »

Parts diagram for Kokusan:
http://www.suzukipartshouse.com/home.as ... 6021160022

Parts diagram for Nippon Denso:
http://www.suzukipartshouse.com/home.as ... 6021160021

As you can see from the parts diagrams, the brush holders are different.
You will need to switch out both the stator & rotor for Nippon Denso parts.

Different voltage regulators are shown, but you can use either or an aftermarket unit.

GT380s & GT550s used the same alternators, so you can use an alternator that was from either bike.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
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tz375
Moto GP
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Joined: Mon Nov 03, 2008 10:47 am
Location: Illinois

Re: Upgrade for Kokusan on my Gt 550

Post by tz375 »

Thomas,
That should be an interesting project. As far as I know the rotor, stator and voltage regulator all have to be swapped out. If you are making extensive changes to the bike, maybe it's appropriate to look at the alternator from a more modern bike. GSXR has lighter alternators that generate more power, but at high revs and they need a stronger (thicker) crank nose.

I would look at any modern bike that is not high revving. Say maybe a Ducati or other twin might be a suitable donor.
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