- Sat Mar 23, 2019 12:38 pm
#81894
Standard enfield pistons are made of melted down rupees mixed with elephant dung. Then half sawn through in an attempt to supply more oil to the bore. As such, they have a tendancy for the crown to collapse after a time trapping the rings in the lands and leading to a loss of compression, light scoring of the bore and burning of oil. (Rather than totally ripping the piston in half like a 500 can). If/how quickly this happens depends on how hard you ride it.
Our hosts "higher" compression piston is similar to a standard one, just more domed (Note "higher" rather than "high"). It is also a fair bit cheaper than a standard one so I use them, I don't think the quality is much better and I didn't really notice a huge difference in power output over a standard one.
I'm not aware of a "high" compression piston for the 350 models? What are you proposing to fit?
The forged piston available from our hosts claims to give a similar compression to the "Higher" compression ones. This is made of real metal in a controlled engineering process and is not half sawn through. As such you could well consider one these to be a good investment. I am moving towards fitting one to my 350. I personally treat Indian pistons as a service item and change them at every de-coke. My current one is getting close to this point as evidenced by the fact I no longer need to use the decompressor to get it over TDC without the clutch slipping.
As ever, the more you tune an engine, the closer you take it to catastrophic failure. That said, bumping the compression from 7.25:1 to 8:1 isn't exactly going to be squealing the rear tyre away from the lights.
