1974 GT750 Rebuild

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burgs
Posts: 70
Joined: Mon Feb 06, 2012 9:07 pm
Location: Hunter Valley NSW Australia

1974 GT750 Rebuild

Post by burgs »

Hi
Finally decided to get the 1974 GT L going again, spent the last few days making room for the job in the workshop with the view to having it ready for the annual Bathurst pre Easter ride.
I bought this bike around 2013, got it going after a bit of work, gearbox detent stuck, carbies with bent needles etc, rode it on a couple of test runs only to find the crankshaft seals were shot.
Parked it up and went on with other projects.
So now with the annual 2021 Bathurst ride approaching and with problems with N0. 1 GT I thought I had better get to work.
Today set about removing the cylinder block, that went well, 6 hours later and a can of penetrant they were off, I have never seen such corroded studs, it had the Dowty seals, but no anti corrosion protection!
The plan is to fit a crankshaft (out of my #1 74L) I have just had rebuilt and balanced.
The bike is what appears to me to be very original, it is an American import, stickers what is left of them, appear to be as per what is described on this site, and old Japanese site. to lazy to look up the correct site.
The rear brake plate doesn't have the cast in wear limits, but has the remains of the stickers, the gear lever housing/cover has the gear positions cast into the casting, my other #1 GTL has neither, the carbies have the stubs for fitting vacuum gauges for tuning as well.
Good thing is it has the original front mudguard, the rear appears to be original also but unfortunately it has a crack, and some extra holes drilled in it, not a big issue and something I can deal with later.
Everything else appears to be original, so I am going to keep it that way with hidden updates.
Burgs
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slosher
Posts: 901
Joined: Fri Sep 23, 2011 6:55 pm
Location: Walsall,Black Country

Re: 1974 GT750 Rebuild

Post by slosher »

Hi Burgs this is my very original "L"
Clicky clicky on the back brake lever it has cast in wear limits
Honestly i think they got what was available on production plus the "L" got a lot of unused RE5 bits and bobs ;)
Attachments
DSCF3747.JPG
GT750L
GT550L
TL1000 97s
T140V
Loctite Trained Engineer :lol:(since having the Bonnie)
burgs
Posts: 70
Joined: Mon Feb 06, 2012 9:07 pm
Location: Hunter Valley NSW Australia

Re: 1974 GT750 Rebuild

Post by burgs »

Hi Slosher
That is a real top job you have done there.
I had the tank and side covers painted a few years ago, cost a fortune and he didn't/couldn't get the fleck right much bigger than original.
The original tank was orange, I still have that on #1.

Burgs
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slosher
Posts: 901
Joined: Fri Sep 23, 2011 6:55 pm
Location: Walsall,Black Country

Re: 1974 GT750 Rebuild

Post by slosher »

Hi Burgs tank and side panels are as it came from Japan :) the crab rail & seat cover have been added oh and both upper pipes have been re-chromed that's it everything else is 1974 it's even got original zinc spokes :ugeek: :lol: :lol: That'll not please Alan :roll:
GT750L
GT550L
TL1000 97s
T140V
Loctite Trained Engineer :lol:(since having the Bonnie)
User avatar
Alan H
Posts: 12104
Joined: Fri Aug 05, 2011 6:38 am
Location: Wombwell, Republic of South Yorkshire

Re: 1974 GT750 Rebuild

Post by Alan H »

It's your bike and if you like 'em, they're obviously fine.
I had SS spokes and rims fitted on my 550J so I don't have to clean the bloody things with wire wool every couple of years....... ;)
Proof that four strokes are over complicated
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slosher
Posts: 901
Joined: Fri Sep 23, 2011 6:55 pm
Location: Walsall,Black Country

Re: 1974 GT750 Rebuild

Post by slosher »

Alan H wrote: Wed Jan 27, 2021 7:35 pm It's your bike and if you like 'em, they're obviously fine.
I had SS spokes and rims fitted on my 550J so I don't have to clean the bloody things with wire wool every couple of years....... ;)
It's no show pony it's a rider it don't warrant a re-build IMO 30k miles so why spend eh Al ;)
GT750L
GT550L
TL1000 97s
T140V
Loctite Trained Engineer :lol:(since having the Bonnie)
User avatar
Alan H
Posts: 12104
Joined: Fri Aug 05, 2011 6:38 am
Location: Wombwell, Republic of South Yorkshire

Re: 1974 GT750 Rebuild

Post by Alan H »

Correctamundo bud!
mexwav.gif
mexwav.gif (16.91 KiB) Viewed 1220 times
Proof that four strokes are over complicated
burgs
Posts: 70
Joined: Mon Feb 06, 2012 9:07 pm
Location: Hunter Valley NSW Australia

Re: 1974 GT750 Rebuild

Post by burgs »

Took the cylinders to work today to put in the my hot wash (I have a small unit in my machine shop that fits motorcycle parts in nicely), they came out clean, but I can now see where someone had been trying to get the cylinder block off before and there are a few what looks like screw driver marks and dents between the mating faces cylinder block to crankcase, not a big issue but makes you wonder. what he/they were thinking.
I stoned the head and crankcase surfaces and they appear to be flat, and the burrs from the butchers efforts have came out okay.
Cylinders have bad score marks in the lower end of the bore, but measure up as standard, I have new over size pistons to go in, and I will drop off the cylinder and pistons to local motorcycle machine shop to bore out tomorrow afternoon, bit too busy to do at work, plus our gear is a bit of over kill. We service Caterpillar engines, I do the machining.
Apart from that I am building a vapor blaster so I can clean up the parts as required.
Sometime over the weekend I hope to strip the crankcase, so far it doesn't appear to have been attacked, by the same person.
There was evidence of water in the crankcase, so suspect water pump seal failure, I had ordered a kit to rebuild the pump just in case and have it on hand.

Burgs
burgs
Posts: 70
Joined: Mon Feb 06, 2012 9:07 pm
Location: Hunter Valley NSW Australia

Re: 1974 GT750 Rebuild

Post by burgs »

Hi
Currently the GT has this Suzuki cap on on the brake reservoir, can any body confirm whether, it is correct for an early February/March build?

Regards
Burgs
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Current Brake Cap 2.jpg
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canaletto5
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Joined: Tue Jul 23, 2013 8:43 pm
Location: Derbyshire

Re: 1974 GT750 Rebuild

Post by canaletto5 »

If you look carefully at this sales brochure you can just see that the cap has a white top to it which I assume is the decal showing the fluid spec.
gt750l.jpg
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