1973 Yamaha 500 DOHC?

Anyone familiar with these? I just picked up a very clean and low
mileage one. Not sure what I'm gonna do with it yet. Trying to decide if
I want to keep it or try trading it for a pre-unit Triumph, or just
selling it outright.

I've got the same issue with a '70 Suzuki T500, except it's not 100%
complete and not as good of shape.

Any feedback on either bike would be great. It may help me decide which
way to go.

Les
(Leaning towards trying to trade for a pre-unit basket)

On 26 Sep, 08:31, Project Magnet #1 <test_spamgour....DeleteThis@cox.net> wrote:
> Anyone familiar with these? I just picked up a very clean and low
> mileage one. Not sure what I'm gonna do with it yet. Trying to decide if
> I want to keep it or try trading it for a pre-unit Triumph, or just
> selling it outright.
>
> I've got the same issue with a '70 Suzuki T500, except it's not 100%
> complete and not as good of shape.
>
> Any feedback on either bike would be great. It may help me decide which
> way to go.
>

I've owned both (well, a GT500, rather than a T500, but it's the same
bike barring the styling and the disc front end).

The Yam 500 twin was an incredibly advanced design for the era, but
the trouble was it wasn't any quicker than the opposition, and slower
than the T500....

The real problem with the early ones was the cylinder head design,
which consisted of two layers, really. The gaskets would leak. They
also ran hot (as a lot of early four-valve heads did) and could burn
out the valves or crack the heads. Especially if you didn't keep an
eye on the valve clearances.

Later models (post about 1976, IIRC) went to a one-piece cylinder head
design.

The Yam also has a balancer shaft, adjusted by a chain, and this can
be tricky to adjust on the earlier bikes. Again, they changed the
tensioning mechanism on later bikes.

If yours is a black & gold one, with a rounded tank and the twin front
discs, it's probably the best model to have, despite the engine
concerns. Later ones had horrible slabby styling and only a single
disc.

If it's rounded styling and a single front disc, it's probably a US
import.

They're quite nice to ride. Very smooth. They don't rev like you think
they should, though. Handling's pretty good. But, to be honest,
they're just rather underwhelming. And not valuable. Decent runners
are £500-600, tatty MoT'd runners less, and superb versions maybe
£750-800.

The T500 is a brilliant bike. Incredibly tough engine, surprisingy
torquey for a stroker, and parts availability is still pretty good
(mostly from the USA). They sold a lot of these things (unlike the
Yam) and they were in production for over ten years (unlike the Yam).
They can be tuned to go like stink, too: someone used to do a water-
cooled barrel conversion for them. Even standard, they'll top 110mph
(the speedo will show much more!)

Downside is the TLS front brake: the later GT had a disc, as I've
said, and disc front ends are a common mod for a T. The GT had
electronic ignition as standard, too, but aftermarket kits for the T
can be had. Tinware is fairly hard to find these days: mudguards,
exhausts, etc, but the stuff is out there.

Only slightly weak spot concerns the top end - again, the cylinder
heads can crack around the spark plug holes, if the plug is over-
tightened. An essential check.

They fetch far more money than XS500s. An early purple and chrome drum-
braker, in really nice order, will easily top four figures: maybe as
much as two grand for a minter. It's really hard to find half-decent
ones for under £800-900.

Depending on what the T needs, my advice would be to flog the Yamaha
and put the money towards sorting out the Suzuki. It really is a very
good bike, and the Yamaha isn't.