Page 3 of 3
Re: pistons/rings ...design and quality
Posted: Sat Dec 19, 2009 1:15 pm
by soosh
sean brady scooters wrote:red ghost wrote:Hi Sean,
I understand what you're saying, but how dose that relate with the exhaust port width being a percentage of the bore size?
on a 200/66mm bore ,a 42mm wide exhaust is roughly 65% of bore...
.66 x 65 =42.9mm
70% would be .66 x 70 = 46.2mm
You can get away with 44.6mm on a 200/66mm on a standard piston.
Re: pistons/rings ...design and quality
Posted: Sun Dec 20, 2009 10:41 pm
by J1MS
What I was trying to find out is how does the ring profile effect this pressure and how much accelerated wear (if any) is caused by the ring type & pressure, and from this info which type of piston ring gives the longest service life depending on the material being used for a cylinder wall (cast iron) on a standard or mildly ported Lambretta... and also which piston ring coating (and there are many types) best suits the Lambretta cylinder for example; Titanium Nitride, Chromium Nitride etc... ?
Re: pistons/rings ...design and quality
Posted: Mon Dec 21, 2009 11:32 am
by soosh
Jesus,i personaly just ride the thing.The shape of the port can allow you to go a bit wider than the 60/70% rule.
Re: pistons/rings ...design and quality
Posted: Mon Dec 21, 2009 1:29 pm
by dsc scotty
Golden eye is a genius with regards to piston rings, made some rings for a an asso piston for me about 10 years ago, they were 1.5mm type these were put on one of my stage 4 tuned cast iron barrels. This barrel piston /ring set up went on to win the LCGB best supporting members championship for three years in a row and is still going strong today. A testement to Goldeneyes skill and knowledge. If you need your ring sorting I,m sure he'll be of assistance.
Re: pistons/rings ...design and quality
Posted: Mon Dec 21, 2009 1:40 pm
by soosh
My ring certainly needed sorting last night,itching like mad.
Re: pistons/rings ...design and quality
Posted: Mon Dec 21, 2009 1:53 pm
by Mag
dsc scotty wrote:Golden eye is a genius with regards to piston rings, made some rings for a an asso piston for me about 10 years ago, they were 1.5mm type these were put on one of my stage 4 tuned cast iron barrels. This barrel piston /ring set up went on to win the LCGB best supporting members championship for three years in a row and is still going strong today. A testement to Goldeneyes skill and knowledge. If you need your ring sorting I,m sure he'll be of assistance.
Goldeneye stayed at my house on Saturday night. Luckily he didn't sort my ring out, but I ever I wanted someone to, he's the man!
Re: pistons/rings ...design and quality
Posted: Mon Dec 21, 2009 7:27 pm
by Andy Pickering
dsc scotty wrote:you need your ring sorting I,m sure he'll be of assistance.
soosh wrote:My ring certainly needed sorting last night,itching like mad.
Mag wrote:Luckily he didn't sort my ring out, but I ever I wanted someone to, he's the man!
MODS lock it down its getting wierd now...
