GT550 crank right outer bearing & oil seal

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jabcb
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GT550 crank right outer bearing & oil seal

Post by jabcb »

Rats! Am working the the GT550 cafe build.

We were assembling the motor today & found out that the right outer bearing is on backwards.
This bearing has a groove for the C-ring that laterally positions the crank. The parts diagram is also wrong. Presumably the shop assembled it as show in the diagram.

How difficult is it for us to flip the bearing around? (Am weighing the tradeoff of fixing it ourselves vs. the delay of having the shop do it.)
Will the oil seal be damaged in the process of removing the bearing?
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
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Re: GT550 crank right outer bearing & oil seal

Post by dollydog »

hi jab, you'll definitely need a bearing puller - those bearings are on TIGHT. you need the type that tucks in behind the bearing, not a 3 leg. i bought one of these kits years ago, and although it's a bit of a pain to set up, it was well worth the money. the 2 black bits at the top of the photo are the sort to use :D
cheers, dd.
https://www.ebay.co.uk/itm/Hub-Bearing- ... rk:33:pf:0" onclick="window.open(this.href);return false;
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jabcb
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Re: GT550 crank right outer bearing & oil seal

Post by jabcb »

Thanks for the info.

Using a tool like that likely will damage the oil seal. Also not sure how to get the bearing off without damaging it. So I’ll order a new seal and have the shop do the fix.
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
Cliff56
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Re: GT550 crank right outer bearing & oil seal

Post by Cliff56 »

Yes, c clip groove is on the inside!
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jabcb
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Re: GT550 crank right outer bearing & oil seal

Post by jabcb »

Quadruple double rats!

Got the crank back from the shop with the bearing oriented correctly. Tried installing the crank & it doesn’t turn!
Compared the dimensions to the specs per service bulletin Specification-7, and the 5 listed dimensions are out of spec.

Don't know what's up. The shop previously rebuilt a few cranks for me & they were fine.
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
karl pa
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Re: GT550 crank right outer bearing & oil seal

Post by karl pa »

That stinks :(
I have my 550 crank and lower case at the shop now, they like having the lower case and installing crank in it. Hopefully won't have issues.
76 GT185
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74 GT750
71 T250 scrambler
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jabcb
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Re: GT550 crank right outer bearing & oil seal

Post by jabcb »

When he flipped the bearing to orient it correctly, he also flipped the drive gear so that is now wrong.
The error for each of the 5 measurements is small but they add up. Combine those errors with the gear on backwards & the crank can’t turn.
But even if it could turn correctly, the points cam can’t engage the locating pin on the drive gear.

I wish I had thought of giving them the lower case half. This is my first triple build & I didn’t know.
You should be ok. If the crank turns, then you don’t have the problems I’m dealing with.
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
Splant
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Re: GT550 crank right outer bearing & oil seal

Post by Splant »

What's happening ,are the flywheel s catching the crankcase? Are you taking it back with the lower crankcase?
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jabcb
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Re: GT550 crank right outer bearing & oil seal

Post by jabcb »

Right flywheel of the left cylinder rubs and the drive gear rubs.

I’m undecided on what to do. I ordered new crank seals today to replace any of the new seal that gets damaged if they have to pull the crank apart.

I’m considering two choices:
1) send the crank & new seals to Bill Bune
2) Give the shop another chance. This time they would get the crank, new seals, Specification-7, pics of a correct crank, and the lower case
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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jabcb
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Re: GT550 crank right outer bearing & oil seal

Post by jabcb »

Ended up sending the crank to Bill Bune.
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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jabcb
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Suzuki 2-Strokes: 69 T350 thru 75 GT750
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Re: GT550 crank right outer bearing & oil seal

Post by jabcb »

Got the crank back yesterday. Fit perfectly. :D
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
daxman
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Suzuki 2-Strokes: A100 GT250 & 4t Yams!
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Re: GT550 crank right outer bearing & oil seal

Post by daxman »

Any recompense from the first shop?
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jabcb
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Re: GT550 crank right outer bearing & oil seal

Post by jabcb »

The local shop rebuilt the crank for the GT250 cafe build & did a bunch of top ends. All of the prior work was fine.
Had I given the shop the lower crankcase half + the service bulletin with the specs, this crank probably would have been fine too.

I’m not going to try to get any $$$ back. There are very few places that work on vintage bikes. I’m not going to poison the well.
The local shop has a pretty low hourly rate. He has a good reputation & knows he screwed up. I see it as lesson learned for him.
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
daxman
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Posts: 348
Joined: Thu Nov 07, 2013 1:59 pm
Country: United Kingdom
Suzuki 2-Strokes: A100 GT250 & 4t Yams!
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Re: GT550 crank right outer bearing & oil seal

Post by daxman »

jabcb wrote:The local shop rebuilt the crank for the GT250 cafe build & did a bunch of top ends. All of the prior work was fine.
Had I given the shop the lower crankcase half + the service bulletin with the specs, this crank probably would have been fine too.

I’m not going to try to get any $$$ back. There are very few places that work on vintage bikes. I’m not going to poison the well.
The local shop has a pretty low hourly rate. He has a good reputation & knows he screwed up. I see it as lesson learned for him.
Fair enough - we all make mistakes,. Good of you to take it on the chin.
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