It’s a ring thing
Piston rings – make one wrong move and ‘tik!’ they snap! But not this time. Decarbonising the pistons for John Naish’s Triumph (see page 96) I reached for the old rings; snapped in half with the end ground to a chisel point, they’re great for scraping carbon from the grooves. But as I gave the ring a tug, nothing happened. I tried again, but it just became oval.
This tickled me so much, I couldn’t resist making imaginative metal sculptures out of the rest. What do you think? Move over Damien Hirst, I’d say...
Yup, it’s that old enemy dud spares once again. Years ago I remember foolishly taking the budget option on a set of rings for my BSA A10; from the outset it smoked badly and didn’t improve with running in. I learned my lesson and bought the more expensive rings, plus another gasket set – and then I had to find the time to do the job all over again.
In fairness, this engine arrived in bits and I haven’t seen it run; maybe these rings actually worked OK, but I’d be surprised if something so flexible was up to the job. I’ve heard ring quality can still be an issue so I went to Triumph specialists Rockerbox (01252 722973) for their recommendation.
“Some of the repro pistons on the market are fine,” said Arthur, “but we fit these American Goetzes.”
So I bought a set. That’s the great thing about parts suppliers whose reputation is also based on rebuilds – they depend on the parts they sell, so you get valuable free advice with everything you buy.