Leak down test with gapless rings in lightweight pistons

jseng1 · Mar 6, 2014

See video of leakdown test on Norton with 15,000 miles on total seal gapless rings and lightweight pistons.

[video]http://www.youtube.com/watch?v=rzp1nEGWLBk[/video]

sportsroof · Mar 6, 2014

Wow! That's impressive sealing! I sometimes bounce off my kickstarter but mine don't seal up quite as well as the one in the video. Hmmm.....
Cheers, Martin

Fast Eddie · Mar 6, 2014

Nice demonstration Jim, especially nice for me to see as I'll shortly be assembling my top end with those same gapless rings. Can't wait

sportsroof · Mar 8, 2014

FWIW I have been using gapless rings in a racing V8 for some years and have been impressed by the way they have kept the seal for so long.
Eddie: is that you in the pic? Cadwell?
Cheers, Martin

Fast Eddie · Mar 8, 2014

sportsroof said:
FWIW I have been using gapless rings in a racing V8 for some years and have been impressed by the way they have kept the seal for so long.
Eddie: is that you in the pic? Cadwell?
Cheers, Martin

Yes and yes Martin!

sportsroof · Mar 8, 2014

V Cool! Trackday or racing? I think the latter maybe. Which club, what series etc? Would love to go watch Commandos racing if near enough to me.
Cheers, Martin

Hobot · Mar 8, 2014

That's interesting way to test compression but my so so rehoned standard ring type Combats keeps mine up too just standing on KS so hard to determine where to leave at TDC. Real compression leak down is a bugger to do on our vertical twins and await a video of how others might do it, especially the part that requires moving pistons just a wee bit off TDC to test bores a where they actually wear that matters. Nice single step on start, I've come to expect every time too. Try the same test after engine and oil are at full heat. Btw is your TS ring set the first or the second one?

jseng1 · Mar 8, 2014

Gapless ring is in 2nd groove. According to some who have actually tried it - it doesn't work well at all in top groove on a Nort (counter to what may work in car racing).

Hobot · Mar 8, 2014

OK thanx for the 2nd ring only Norton alert JIm. If ya dig into the TS principle you may discover its only helpful in lower rpms as at hi rpm there's nil time to blow past ring gaps so not a top end power helper and some shun TS for this hi rpm reason. I don't know if "hi" Norton twin rpm counts though but likely does some after iso isolation rpm. Here's TS's factoids to take into account.

http://www.totalseal.com/Techpage.aspx

Fast Eddie · Mar 8, 2014

sportsroof said:
V Cool! Trackday or racing? I think the latter maybe. Which club, what series etc? Would love to go watch Commandos racing if near enough to me.
Cheers, Martin

It was in British Historic Racing, but I've not raced for a few years now, just limit myself to track events like Beezumph and Festival of 1000 bikes these days.
And it's not a Norton (never reached one) its loosley based on a Triumph but was 906cc with 8 valve NRE top end end, 180 billet NRE crank, etc. in a very lightweight Dresda chassis. To be very honest, the bike was better than me!

sportsroof · Mar 8, 2014

Hey, at least you got out there and did it! I still plan to get out and watch more bike and car racing (and participate but car stuff) now that I'm semi-retired.
Cheers, Martin

acotrel · Mar 8, 2014

I AM fully retired and currently running short of cash. My Seeley 850 is coming up so well that I must race it again. It is a matter of experiencing the achievement. I'm fairly confident that with it, I can blitz most of the guys in it's race class. I'm getting too old to work to finance my racing, so It means a sacrifice of something to find the readies. However I know I have to do this. It won't be about exhibition races or displays, the only way to go is to get real and burn their backsides.

Leak down test with gapless rings in lightweight pistons

Similar threads