Suzuki GT500

Photos and progress of your restorations, even bikes you had but no longer own.

Moderators: oldjapanesebikes, H2RICK, Suzsmokeyallan

Pmd31421
On the street
Posts: 24
Joined: Sun Feb 23, 2020 3:44 pm
Country: Uk
Suzuki 2-Strokes: Gt500 / 1976

Suzuki GT500

Post by Pmd31421 »

Hi just started my GT500 after full restoration .
Carbs were ultrasonic cleaned and new jets fitted . However it runs fine on choke , but when comes off choke it slowly dies on won’t tick over .
Also how do you get the center stand spring onto the stand ? It’s an absolute ##%##
karl pa
To the on ramp
Posts: 490
Joined: Sat Sep 05, 2015 3:14 pm
Country: us
Suzuki 2-Strokes: GT
Location: southeast pa

Re: Suzuki GT500

Post by karl pa »

When you say new jets fitted, did you replace with mikuni jets or aftermarket? some aftermarket jets will give you trouble.
If it runs on choke but not without, it is probably a problem with idle/pilot circuit, clogged or restricted.
If I remember correctly it is easier to put the spring on when the stand is up. It is much easier if mufflers removed allowing stand to go up even more.
76 GT185
77 GT250
77 GT380
76 GT500
73 GT550
73 GT750
74 GT750
71 T250 scrambler
75 T500 cafe
Pmd31421
On the street
Posts: 24
Joined: Sun Feb 23, 2020 3:44 pm
Country: Uk
Suzuki 2-Strokes: Gt500 / 1976

Re: Suzuki GT500

Post by Pmd31421 »

Thanks for info , i think they were aftermarket .....Damm . Looks like it’s carbs off again .
karl pa
To the on ramp
Posts: 490
Joined: Sat Sep 05, 2015 3:14 pm
Country: us
Suzuki 2-Strokes: GT
Location: southeast pa

Re: Suzuki GT500

Post by karl pa »

I spray carb cleaner and air through all the passages and jets to check flow, sometimes it takes me several cleanings to get clear
76 GT185
77 GT250
77 GT380
76 GT500
73 GT550
73 GT750
74 GT750
71 T250 scrambler
75 T500 cafe
abotech
Still in the Driveway
Posts: 5
Joined: Sat Oct 08, 2016 7:15 pm
Country: United States
Suzuki 2-Strokes: t500j gt500 76 t250 71

Re: Suzuki GT500

Post by abotech »

Springs are easy,, Put one end in vise hook a piece of chain hanging to the floor. Stand on chain to stretch out spring, install washers or pennys between coils. install spring and remove washers.
Pmd31421
On the street
Posts: 24
Joined: Sun Feb 23, 2020 3:44 pm
Country: Uk
Suzuki 2-Strokes: Gt500 / 1976

Re: Suzuki GT500

Post by Pmd31421 »

Brilliant that worked so easy ......thanks
Pmd31421
On the street
Posts: 24
Joined: Sun Feb 23, 2020 3:44 pm
Country: Uk
Suzuki 2-Strokes: Gt500 / 1976

Re: Suzuki GT500

Post by Pmd31421 »

Hi ultrasonic cleaned the carbs again , put carb cleaner thro them , blew all out with compressed air and fitted all new Mikuni jets .
Bike now runs better on choke , will hold off choke for about 20 secs then starts spitting or hissing until it dies........ ideas ?
karl pa
To the on ramp
Posts: 490
Joined: Sat Sep 05, 2015 3:14 pm
Country: us
Suzuki 2-Strokes: GT
Location: southeast pa

Re: Suzuki GT500

Post by karl pa »

Is this after warmed up? Does it run ok when on throttle? my GT500A doesn't like idling until warm, I need to blip the throttle to keep running till warm.
Did you take it for a run? sometimes it helps to give it a good run.
76 GT185
77 GT250
77 GT380
76 GT500
73 GT550
73 GT750
74 GT750
71 T250 scrambler
75 T500 cafe
Pmd31421
On the street
Posts: 24
Joined: Sun Feb 23, 2020 3:44 pm
Country: Uk
Suzuki 2-Strokes: Gt500 / 1976

Re: Suzuki GT500

Post by Pmd31421 »

Hi started bike this morning . Ran ok on choke , misfired on idle but ran for 5 or so minutes .
Then revs went mad......wouldn’t stop . Turned bike off , pulled spark plug caps off ......still screaming away .........turned fuel off .......still wouldn’t stop . In the end undid a spark plug and it stopped .
Spark plug was white when removed .........any help
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Evans Ward
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Country: USA
Suzuki 2-Strokes: 76 GT750, 72 H2 750, 84 RZ350
Location: Macon, GA. USA

Re: Suzuki GT500

Post by Evans Ward »

I’d check throttle cable routing from throttle tube to carbs including free play needed at both ends. Usually easier to do and see with fuel tank removed. Have you lubed them recently?
1976 Suzuki GT750 (Maui Blue), 1972 Kawasaki H2 750 Mach IV (Candytone Blue), 1984 Yamaha RZ350 (KRR- Yellow/ Black).
Pmd31421
On the street
Posts: 24
Joined: Sun Feb 23, 2020 3:44 pm
Country: Uk
Suzuki 2-Strokes: Gt500 / 1976

Re: Suzuki GT500

Post by Pmd31421 »

Yeah throttle cable ok and really free and smooth .Both ends have free play .
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Evans Ward
To the on ramp
Posts: 326
Joined: Mon Oct 24, 2016 12:35 pm
Country: USA
Suzuki 2-Strokes: 76 GT750, 72 H2 750, 84 RZ350
Location: Macon, GA. USA

Re: Suzuki GT500

Post by Evans Ward »

Carb slides in correctly and not sticking as checked with engine off?
1976 Suzuki GT750 (Maui Blue), 1972 Kawasaki H2 750 Mach IV (Candytone Blue), 1984 Yamaha RZ350 (KRR- Yellow/ Black).
karl pa
To the on ramp
Posts: 490
Joined: Sat Sep 05, 2015 3:14 pm
Country: us
Suzuki 2-Strokes: GT
Location: southeast pa

Re: Suzuki GT500

Post by karl pa »

Pmd31421 wrote:turned fuel off
Just curious how you turned the fuel off, do you have a manual shutoff?
Sounds like it could be an air leak on intake boots or carbs.
Another way to kill is to put in gear and release clutch while holding brake, stall it.
76 GT185
77 GT250
77 GT380
76 GT500
73 GT550
73 GT750
74 GT750
71 T250 scrambler
75 T500 cafe
Pmd31421
On the street
Posts: 24
Joined: Sun Feb 23, 2020 3:44 pm
Country: Uk
Suzuki 2-Strokes: Gt500 / 1976

Re: Suzuki GT500

Post by Pmd31421 »

Hi , I turned ignition and kill switch off . Pulled off spark plug caps . Disconnected petrol pipes from fuel tap so no fuel was going into carbs . It was still screaming at full revs. Never thought about sticking it in gear "..........I undid one spark plug and it stopped running
karl pa
To the on ramp
Posts: 490
Joined: Sat Sep 05, 2015 3:14 pm
Country: us
Suzuki 2-Strokes: GT
Location: southeast pa

Re: Suzuki GT500

Post by karl pa »

I would look for air leaks or partial restriction in carbs. sounds like a lean mixture issue. Float height set right ?
My GT550 ran away, that's how I know about putting in gear to stall.
76 GT185
77 GT250
77 GT380
76 GT500
73 GT550
73 GT750
74 GT750
71 T250 scrambler
75 T500 cafe
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