1973 T500 cafe build

Retro, Wild, Cafe, etc. The stuff only your imagination can come up with.

Moderators: oldjapanesebikes, H2RICK, Suzsmokeyallan

User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

1973 T500 cafe build

Post by jabcb »

Had absolutely no need for another project but got one anyways.

The bike is a T500/GT500 combo. T500 frame + a GT500 front end. Motor VIN is for a GT500. Spare motor is the 73 T500 motor without a top end.
Imagecafe-T500-0685 by jabcb, on Flickr

How do I tell if the motor has the T500 or GT500 top end?
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
dollydog
Yeah Man, the Interstate
Posts: 630
Joined: Fri Aug 11, 2017 7:09 am
Country: england
Suzuki 2-Strokes: several gt250 ramairs

Re: 1973 T500 cafe build

Post by dollydog »

according to the parts book, there is no difference between the 73 t500 heads and barrels and the 76 gt500 heads and barrels :D
i know some of them had weird pistons, but memory aint what it was :D
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.
User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: 1973 T500 cafe build

Post by jabcb »

Thanks. I usually check before asking. The design change was between J & K models, and I thought it was later.

Am targeting a look similar to our GT250 cafe project, except for the bars & pegs. No rearsets & I might stick with the drag bars that are on it.
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
dollydog
Yeah Man, the Interstate
Posts: 630
Joined: Fri Aug 11, 2017 7:09 am
Country: england
Suzuki 2-Strokes: several gt250 ramairs

Re: 1973 T500 cafe build

Post by dollydog »

talking of handlebars - now the old back can't cope with clip-ons :D i normally use plain straight bars. get some 22mm o/d aluminium thick wall tubing - 16mm i/d - about 750mm long is perfect. grips and throttle fit perfect and with a good polish they look ace. and save weight :D oh yes, they are about a quarter the price of shop bought straight bars.
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.
User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: 1973 T500 cafe build

Post by jabcb »

Split the cases today.
Good news is that the crank feels ok. Didn’t notice any rough spot. And the tranny gears look fine.
Imagecafe-T500-0735 by jabcb, on Flickr

But there is also some bad news. One of the topside crankcase bolts was rusty and snapped off.
A few other topside crankcase bolts were rusty — I’ll replace them.
Imagecafe-T500-0736 by jabcb, on Flickr

One of cylinder studs is rusty too. Should I have that replaced or just clean it up?
Imagecafe-T500-0737 by jabcb, on Flickr
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
dollydog
Yeah Man, the Interstate
Posts: 630
Joined: Fri Aug 11, 2017 7:09 am
Country: england
Suzuki 2-Strokes: several gt250 ramairs

Re: 1973 T500 cafe build

Post by dollydog »

looking at the photo, the bottom of the stud looks like it's being eaten away? i would definitely replace it and smear some copper grease on the studs when you replace the barrels - makes them so much easier to remove in the future :D
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.
sportston
Expert racer
Posts: 1119
Joined: Wed Jul 10, 2013 12:04 pm
Country: England, UK
Suzuki 2-Strokes: FZ50, GP100, RG125 Gamma, GT380, Bandit 1200S

Re: 1973 T500 cafe build

Post by sportston »

dollydog wrote:looking at the photo, the bottom of the stud looks like it's being eaten away? i would definitely replace it and smear some copper grease on the studs when you replace the barrels - makes them so much easier to remove in the future :D
cheers, dd.
Clean it well then, soak well with duck oil or plusgas. Use some heat (not so much that you will melt the casing!) to help avoid snapping it off when you remove it.
Nice bike. Looks like a good base to start from.
titan performance
Expert racer
Posts: 1306
Joined: Wed Oct 13, 2010 2:55 pm
Country: England
Suzuki 2-Strokes: TS100, T200, GT250, T500, GT500, GT550, GT750, GS750
Location: Southeast England
Contact:

Re: 1973 T500 cafe build

Post by titan performance »

Looks like a nice find. The T 500 pistons had thick rings with a light groove running around the centre of them, and the piston had a series of grooves in it below the rings. A change came with the GT. Thinner rings, and no piston grooves. Although they look different, they are interchangeable, and as I understand it, the later ones are better/stronger.
Keeping old 2 strokes alive !
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: 1973 T500 cafe build

Post by karl pa »

titan performance wrote: The T 500 pistons had thick rings with a light groove running around the centre of them, and the piston had a series of grooves in it below the rings. A change came with the GT. Thinner rings, and no piston grooves.
? My 76 GT500 has the oil grooves on the pistons and rings, although it is early in the model year, maybe later ones changed.
I replaced the pistons and rings in my 75 T500, with 750 ones with thinner rings and no oil grooves.
76 GT185
77 GT250
77 GT380
76 GT500
73 GT550
73 GT750
74 GT750
71 T250 scrambler
75 T500 cafe
titan performance
Expert racer
Posts: 1306
Joined: Wed Oct 13, 2010 2:55 pm
Country: England
Suzuki 2-Strokes: TS100, T200, GT250, T500, GT500, GT550, GT750, GS750
Location: Southeast England
Contact:

Re: 1973 T500 cafe build

Post by titan performance »

I would think the pistons in you GT had been changed along the way Karl. I've never seen a GT with T pistons from original, and I have seen a few !
Keeping old 2 strokes alive !
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: 1973 T500 cafe build

Post by karl pa »

My GT500 was bought used in 1980 by my father in law, so it is possible, however my spare GT500 engine also has oil grooves on piston and rings, both engines are standard bore, so I am not sure why both would have replaced pistons.
76 GT185
77 GT250
77 GT380
76 GT500
73 GT550
73 GT750
74 GT750
71 T250 scrambler
75 T500 cafe
User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: 1973 T500 cafe build

Post by jabcb »

Didn’t know about variations in T500/GT500 pistons.
I needed 2nd OS pistons & ended up getting Wisecos. (2nd OS Wossners were out of stock in the US. 2nd OS NOS are NLA & weren’t listed on eBay.)

Sent the crank out & am hopeful that the verdict is that the bearings are OK.

The guidance on replacing the cylinder stud reminds me about the old Clint Eastwood / Dirty Harry quote about knowing your limitations.
So I will take the crankcase to a shop to replace the bad stud & to remove the broken bolt.
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
User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: 1973 T500 cafe build

Post by jabcb »

Had a bit of luck. The bearings were ok & I got the rebuilt crank back.
Maybe I should buy a lottery ticket.
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
sportston
Expert racer
Posts: 1119
Joined: Wed Jul 10, 2013 12:04 pm
Country: England, UK
Suzuki 2-Strokes: FZ50, GP100, RG125 Gamma, GT380, Bandit 1200S

Re: 1973 T500 cafe build

Post by sportston »

Well that is good news. How have you got on with the studs?
User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: 1973 T500 cafe build

Post by jabcb »

Planning on taking the crankcase to a shop next week.

Made up for good luck on the T500 with bad like on the GT550. (See pics in that topic.)
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
Post Reply