GT380 Rear Wheel Hub

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grumpy56
To the on ramp
Posts: 218
Joined: Thu Nov 20, 2014 11:08 pm
Country: USA
Suzuki 2-Strokes: 1970 T350 Restored; 1972 GT380 Build
Location: Yorba Linda, CA

GT380 Rear Wheel Hub

Post by grumpy56 »

Bought a rear hub off of a 1974 model and a bearing kit for a 1972 (Pivot Works PWRWS-27-000) and noticed that the bearing sizes are different. Same part numbers in the Suzuki Parts Catalog, but looks like the 72 used different bearings in the hub. Is that correct? Also, if I use the 1974 hub, are there any other similar issues between years in the rear wheel assembly Thanks.
dollydog
Yeah Man, the Interstate
Posts: 633
Joined: Fri Aug 11, 2017 7:09 am
Country: england
Suzuki 2-Strokes: several gt250 ramairs

Re: GT380 Rear Wheel Hub

Post by dollydog »

hi grumpy, as far as i know they are the same. the only thing i can think of is one uses sealed bearings and the other doesn't. or one is sealed one side and the other is sealed both sides :D
cheers, dd.
p.s. have you got all 3 bearings? if you take the numbers off the bearings when you take them out, just order that size instead of a special kit, you'll find it far cheaper.
GTS250 road registered. TS250 engine, Ramair frame.
GT250 big bang road registered. Both pistons fire the same time. USD forks.
GT285 road registered. Overbored - 58mm and TS125 +2 pistons fitted.
GT10 road registered. '65 T10 engine, GT250 frame.
grumpy56
To the on ramp
Posts: 218
Joined: Thu Nov 20, 2014 11:08 pm
Country: USA
Suzuki 2-Strokes: 1970 T350 Restored; 1972 GT380 Build
Location: Yorba Linda, CA

Re: GT380 Rear Wheel Hub

Post by grumpy56 »

Thanks Dollydog. The old ones I removed from the hub are only sealed on one side. I do have the two old ones and will have to look to see if they have P/Ns. I should have just gotten a 1972 hub so I don't run into further problems with differences between years (although the parts catalogue indicates the same P/Ns for most rear wheel parts).
grumpy56
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Posts: 218
Joined: Thu Nov 20, 2014 11:08 pm
Country: USA
Suzuki 2-Strokes: 1970 T350 Restored; 1972 GT380 Build
Location: Yorba Linda, CA

Re: GT380 Rear Wheel Hub

Post by grumpy56 »

All of the aftermarket bearing suppliers (and Partzilla) are showing a 6205 (52mm) bearing for the sprocket side of the hub for a 1972 and a 6203 (40mm) for all the other years. The inside diameter is different too (25mm) versus 17mm on the brake side. Boy is THIS confusing......
dollydog
Yeah Man, the Interstate
Posts: 633
Joined: Fri Aug 11, 2017 7:09 am
Country: england
Suzuki 2-Strokes: several gt250 ramairs

Re: GT380 Rear Wheel Hub

Post by dollydog »

hi grumpy, if i remember rightly, which i do sometimes, on the sprocket side of the wheel you've got the sprocket carrier, ok? sticking out of that is a double sized spacer [number 10 on the photo i'm gonna post. then the bearing [number 19] then a spacer, which is afaik 25mm o.d. and 17mm i.d. [number 11]. the oilseal goes over that [25mm i.d. number 25]. hope that all makes sense? think you'll find the smaller i.d bearings are for the wheel and the larger i.d. bearing is for the sprocket carrier. don't forget, there are 3 bearings. hope that helps, if it doesn't you can kick me next time you see me :D
cheers, dd.

1972 gt380 rear wheel:
Image
GTS250 road registered. TS250 engine, Ramair frame.
GT250 big bang road registered. Both pistons fire the same time. USD forks.
GT285 road registered. Overbored - 58mm and TS125 +2 pistons fitted.
GT10 road registered. '65 T10 engine, GT250 frame.
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jabcb
Moto GP
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Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: GT380 Rear Wheel Hub

Post by jabcb »

The AllBalls website currently doesn’t list the rear wheel bearing kit for the GT250, GT380 or T500,
Most likely there was an error in the AllBalls info somewhere. And not knowing how to correct it with certainty, they just got rid of the rear wheel bearing listings for those bikes.

Some time ago I upgraded my GT380 cafe build to wider rims. At the rear, that was easily done by swapping out the rear wheel for a T500 wheel. It fits without any mods. I replaced the rear wheel bearings with the AllBalls specified bearing kit, which fit perfectly.
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
grumpy56
To the on ramp
Posts: 218
Joined: Thu Nov 20, 2014 11:08 pm
Country: USA
Suzuki 2-Strokes: 1970 T350 Restored; 1972 GT380 Build
Location: Yorba Linda, CA

Re: GT380 Rear Wheel Hub

Post by grumpy56 »

Thank you both. Yes, the sprocket carrier bearing is a 52mm and I think the LH bearing on the hub is a 40mm with 17mm bore (6203). I will just use the 74 hub I have and buy a 6203 to press into the left side. It is really confusing when the aftermarket includes two 52mm bearings in a "kit" (I noticed several different ones on the web). Also, several others just indicate the years "73-77", but as far as I know, the 72 is no different and would use the same "kit". Ah retirement fun.......................
dollydog
Yeah Man, the Interstate
Posts: 633
Joined: Fri Aug 11, 2017 7:09 am
Country: england
Suzuki 2-Strokes: several gt250 ramairs

Re: GT380 Rear Wheel Hub

Post by dollydog »

that's why, if i strip a new [to me] hub down, i knock the bearing out, clean it, read the size that's etched on it and write it down. so my little notebook would say something like 6301 fr/os - 2 off. 6302 fr/ns - 1 off. suzuki gt???/kawasaki???/yamaha??? [examples]. then go on fleabay and type in koyo 6301 and 6302. i nearly always use koyo bearings. when they arrive i check the number on them, look in the notebook where they are for, then throw them in the freezer for a few hours before fitting. so much easier than trying to remember which bike they were for - especially at my age :lol:
cheers, dd.
GTS250 road registered. TS250 engine, Ramair frame.
GT250 big bang road registered. Both pistons fire the same time. USD forks.
GT285 road registered. Overbored - 58mm and TS125 +2 pistons fitted.
GT10 road registered. '65 T10 engine, GT250 frame.
grumpy56
To the on ramp
Posts: 218
Joined: Thu Nov 20, 2014 11:08 pm
Country: USA
Suzuki 2-Strokes: 1970 T350 Restored; 1972 GT380 Build
Location: Yorba Linda, CA

Re: GT380 Rear Wheel Hub

Post by grumpy56 »

That's a good way to do it dolly dog. I do save the old bearings, at least for a while, to use to drive in the new ones as far as I can before getting a socket or broom handle. However, I do have a bunch of junk, er ah I mean parts around here that I have no clue where they came from or what they go to. With this 380 though I am being alot more organized. I wonder why???/Gotta be the cheap wine.
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