WTB GT550 starter motor

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tz375
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Location: Illinois

WTB GT550 starter motor

Post by tz375 »

A buddy of mine brought a box of broken starters over and we concluded that the Kokusan with the rebuilt armature had stripped the gear at the end of the shaft. Second unit was from a GS750 and is identical in fit to a GT750 so that's back to front for a 550. His third one was another Kokusan and was a real mess with broken leads inside and when we tried that armature in the rebuilt field coil housing it ran sometimes as if it had a dead segment or two.

I have two types of GT750 starters but the wiring to the brushes is reversed and the end cap is also different, and neither is the same design as a 550 type.

Looking at the 550 and 750 parts books, I see Kokusan on a 550 but not on 750, but Denso fitted to both with the same armature, so one possibility is to get a Denso starter and see if it works and if not, maybe rebuild it with some parts from a GT750 Denso starter.

Or see if there's an equivalent new starter motor available but I have no idea what would fit a 550.

Any thoughts or anyone got a good working spare starter motor for very few drinking vouchers?
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jabcb
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Suzuki 2-Strokes: 69 T350 thru 75 GT750
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Re: WTB GT550 starter motor

Post by jabcb »

Suzuki modified the starter motor clutch because the early design had a tendancy to explode.
See Service Bulletin GT-26 for info on it: h[url]ttps://ozebook.com/compendium/techbuls/SerBulletin%20GT%20022-26.pdf[/url]

Some GT550 owners with the early starter clutch switched to kick start only.
An option for your GT550 worth thinking about.


My ’72 GT550 cafe build had an exploded starter clutch. Bought it some years ago as a fugly project bike. Back then used upgraded starter clutches & 4LS brakes went for reasonable money on eBay. Definitely is getting harder to find good used parts for reasonable money.
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
09 Triumph Bonneville SE
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tz375
Moto GP
Posts: 6204
Joined: Mon Nov 03, 2008 10:47 am
Location: Illinois

Re: WTB GT550 starter motor

Post by tz375 »

Thanks.

He already replaced the old style clutch with the later type ( I think) but he tends to forget which parts he fitted last time around. :wth:

There's a new Kokusan armature on ebay from the UK at around 400 bucks which is a just a touch on the expensive side of ridiculous. It's possible to get an armature rewound. he had that done before, and that's the one with the stripped/worn gear end. I might just get my machinist to spin the old grubby armature in the lathe and take a light skim to clean the commutator, abut there's no guarantee it's electrically sound.

Someone must have a spare from all those motors that have been stripped over the years. I inherited a number of GT750 starters but unfortunately they won't fit.
Cliff56
On the street
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Joined: Tue Aug 22, 2017 5:29 pm
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Suzuki 2-Strokes: Original owner GT550L

Re: WTB GT550 starter motor

Post by Cliff56 »

Just picked up a complete GT550A bottom end. I'll pull the starter out and check it over!
Cliff56
On the street
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Joined: Tue Aug 22, 2017 5:29 pm
Country: Canada
Suzuki 2-Strokes: Original owner GT550L

Re: WTB GT550 starter motor

Post by Cliff56 »

Looks Perfect!!
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