Suzuki 1972 GT750J Two-Stroke Question.

The Suzuki 1972 GT750J Two-Stroke was the first Japanese water cooled
motorcycle, two stroke or four stroke (Scott made a water cooled
two stroke in the 1930's).

Is the Suzuki 1972 GT750J Two-Stroke the largest production
two stroke motorcycle made at being 750cc? Did anyone make a bike
larger than 750cc except race bikes. (I've heard someone made a
1000cc race bike but never made it into production for the public).

My last question is why is it that most two strokes even models
from the 1980's and 90's have a low milage between rebuilds (like
20,000 to 30,000 miles) but the Suzuki GT750's usually get between
90,000 and 100,000 miles before a rebuild. I've never heard of two
strokes getting almost Goldwing like mileage from an engine. Is this
true and how did they do this?

 

Yamaha exhibited a liquid-cooled four-sylinder two-stroke 750 road bike
but never put it into production. Obviously Kawasaki made a 750cc
two-stroke as well. I've never heard of anything larger.

It does? Nonsense.

I've never heard of any GT750 doing the sort of mileage you suggest
without needing some attenion. However, remember that the bike was, in
two-stroke terms, very mildly tuned.

250cc two-strokes of the era were knocking out 30bhp or close to it, and
the GT750 made 70bhp or thereabouts. Also, the liquid cooling certainly
helped.

They were tough engines, but not as tough as you've been told.

 

Do they? They used to struggle to get a couple of thousand between
blow-ups, if my mates back in the '70s were anything to go by.

I guess that, as they were only making the same sort of power as the
air-cooled kwak trips, the tolerances weren't that much lower than
that, whereas later bikes would have used the fact of air-cooling to
make everything a much tighter fit, IYSWIM.

But flip wibble do, 'cos I'm making htis up as I go along

--
_______
..'_/_|_\_'. Ace (brucedotrogers a.t rochedotcom)
\`\ | /`/ GSX-R1000K3
`\\ | //' BOTAFOT#3, SbS#2, UKRMMA#13, DFV#8, SKA#2
`\|/`
`

 

ITYM later bikes would have used liquid cooling to use tighter
tolerances, unless you know something I don't. (Which wouldn't
be unusual)

 

Well, I had a GT750M, (L reg IIRC) and I done well over the 100K miles on
it. Apart from regular decoking, and very regular plug changes, I had no
major work done at all. I had it with just over the 1k on when I bought it
from Coburn & Hughes in Haringey. Did all the servicing myself, (what there
was of it!) and it would just run and run. Biggest problem I ever had, was
battery/charging problems. Never did get that sorted 100%. Oh, and it never
saw the inside of a garage, coz where my mum and dad lived we never had one.
Only ever stood in the street, come rain, sun or snow.

Shame Suzi finish isn't like that nowadays.

 

Fair enough. There's always the exception. The owners' group goes into
long detail about crank prolems...

I remember them..... Slow-Burning Fuse, they were known as. Or Slow-Worm
& Screws.

 

I remember there being issues about cranks, but I must admit to upping the
oil injection a little [1] on mine to be safe. Hence the reason for many a
clogged plug and loadza [2] of smoke when giving it the beans after a city
trundle.

Them be the ones ;o) also used to sell aeroplanes, out of Southend Airport
IIRC?

[1] Upped quite a bit akshually.
[2] Like a smoke screen! The greenies would have a baby now if they saw my
old kettle being given the beanz down the A10, long, long before the joy of
Gatso's.

 

YT correctly.

--
_______
..'_/_|_\_'. Ace (brucedotrogers a.t rochedotcom)
\`\ | /`/ GSX-R1000K3
`\\ | //' BOTAFOT#3, SbS#2, UKRMMA#13, DFV#8, SKA#2
`\|/`
`

 

The Older Gentleman says...

Ther number plate slogans used to read "I chose to use Coburn and
Hughes".

Round here one wag who had grief from them changed his with Lettraset
to read "I chose to be abused by Coburn and Hughes"

 

Greybeard says...

They'd take anything in part-exchange as well. You could take a TV,
garden furniture, packet of cornflakes and even your dead granny's
ashes in and they'd give you a few quid for them against a new bike.

 

Indeed. I'd forgotten that.

LOL

 

Heh!

That's dead right an' all. I'd forgotten about that.
I paid my deposit with one of them LED watches that was all the craze at the
time. All black, and you had press the button to see the time! IIRC it cost
me about a tenner from the "new-on-the-block" Dixons. Got about fifty quid
towards my deposit though.

 

It was somewhere around Barstow, on the edge of the desert, when the

Bunch of Cunts. I was not amused by Coburn and Hughes.

 

If it was a Sinclair Black Watch, it's probably worth ten times that
now.

 

Nope, thank goodness it wasn't. but it was something similar. Funny how
things turn round though.

 

I bought a number of bikes from them over the years. The main reason was
that they where just down the road from my Dad's shop and I worked there
most weekends.

Found them be very helpful, but the workshop monkeys were shite!

 

The Older Gentleman wrote

Really?

I must make plans to find a way into that corner of the loft.