SC500 Parts Book

You can find them here and hopefully you’ll find the useful. Its a good, full size A4 book, and hopefully scanning will make it less easy to damage it.

Yamaha SC500 Photo's

Yamaha TY250, another Yamaha

It’s in good condition and well looked after by Neil (its previous owner) and the only issue (for me anyway) is that its not road registered.

Matching frame and engine numbers and also a nice Sammy Miller tank and seat unit (unaffected by ethanol it seems). The engine has had a recent rebuild and starts and runs nicely. The TY250 is a completely different bike from the TY175, a lot longer and heavier and rides and turns completely differently.

There are some nice features, including matching frame and engine numbers, stainless front exhaust and modified (to the right place) footrests.

Yamaha TY250 (1978)

Runs well, with a recent engine rebuild

At the time of writing I’ve not yet trialled the bike, as snow has taken out all the local trials. Hopefully 2/Jan back at Clyro will be the next running event.

I’ve sent an email to Yamaha UK Customer services and the dating letter (for 1978) is on its way. Given the sub zero temperatures in the shed and the ongoing SC500 work, I’ve not really had the chance to give the bike the once over, but all seems good.

Haynes Internal Combustion Engine Model Kit

I’d bought here a model engine via Amazon , one which came with good reviews and subsequent to purchase an endorsement from Top Gear. There is an Airfix which doesn’t get quite the same reviews. The Haynes model comes with its own Haynes manual (of course) which apart from the addendum to cover some mistakes with the distributer / cylinder number seems pretty accurate.

Cylinder head

Whilst I don’t think that anyone will have a problem with the kit, even engine novices, it may be harder for those who don’t know the difference between their camshafts and crankshafts.

The model is a good size, the plastic quality is good and it is assembled using good (metal) self-tapping screws. There is a screwdriver provided but its a bit small, so having a smaller cross-head screwdriver will allow you to get some of the screws in further and better seated. You’ll also want to have a good DIY or model knife (like a stanley knife) to cut the pieces from the sprags and tidy them up. My 10 year-old daughter kept me in line and ensure that I read the instructions.

Engine Block

It took me around 2.5 hours to build, which wasn’t bad and I didn’t rush. Daughter attention span was variable due to the Wii being used in the other room. Its a good model and seems to run and work well and does provide an insight to the uninitiated on the workings of a 4-stroke petrol engine. Shame most of the stuff in the shed is 2-stroke !

Completed model

Couple of things to watch for:
– there are spare screws and getting them to start as self tappers can be fiddly. The supplied screwdriver is magnetic but not that beefy. There are no spare springs
– when assembling the lower cylinder head, make sure the two plates are located correctly otherwise you’ll find the valve stems don’t line up correctly and will not run freely.
– the two metal rods are of different lengths. The shorter one is for the rockers and the longer one, with the flat on it, is for the cam / camshaft.

Really enjoyable fun to build and is pretty representative. Now to get down the shed and fix the real things.