Hi
Started running in my pts 21 and noticed after two tanks there is no pinch
I wondering if I got a Pre run engine the piston and sleeve didn't look run
When I had it apart to flush it how can u tell if it's Pre run thanx

We use the 5 (41615) with the 2660 pipe. At Arcadia, using the Flash .12 PTS, we were getting about 5:30 running hard with plenty of smoke. However, normally the longer header will give you more run time. What engine are you running?

250-260 deg. F ~130C (summer ambient ~30)

It says it on the box. Right below 'PTS' it would say 'BREAK IN'

I just broke in a 2012 35+21 and I can tell you it still had the "Nova pinch" and took quite a bit of time on the breakin bench to get it to loosen up enough to finish it in the car without fear of damaging it.
This weekend I preped two KEEP-ON .21 for bench running. One of the things that I noticed was the pinch. There is exactly 3mm worth of pinch honed into the sleeve. What I hope this means is less bench running.

Thanx for the replies it didn't have break in
On the box I'll keep going and hope I havn't
Got a dud motor never had a motor like this
Normally a lot of pinch I'll see what happens
Thanx

35 plus 21
Kangaroo
Kappo
i can get them all at the same price which one is better of the 3 in stock form cheers

35+21 is the better engine.

Thanks Uriah

Re. head clearance Keep On .21s

The stock engine comes with 2x 0.2mm aluminium and 1x 0.1mm brass shims. With all 3 of them used, head clearance is about 0.62mm using the 'solder squish' method. I also noticed the Keep On uses a No.8 plug. Would you recommend removing the 0.1mm shim to make the head clearance closer to the 'generally recommended' 0.5mm ? With a colder plug, I supposed reducing head clearance will advance ignition and make the engine make more lower/mid end power. What are your settings ?

Thanks

You can always give it a try and see what it does.

Get a set of shims, in these days Novarossi has also a .15 shim so you can replace the 0.2 for a 0.15 for maybe a better finetuning if removing 0.1mm is too much.

I would not take the risk unless you are racing at high altitude.

For better bottom end you can just try the 6-fin header.

if you still want to play with head shims, remember that Keep-on .21 is sper long stroke and the correct head shims are the ones with "XL" in the end of product code.

An actual head clearance of 0.50~0.55mm is usually fine, so make sure your engine has 0.62 and you can try to reduce 0.05mm only.

For the plug stay with 8TGH, it works real nice and is a lot more safer to avoid glowplug failures "from nothing" which can be a common and expensive issue when using 7TGF.

Temperature: do not look at temperature, only as reference, due to the had design and depending on track layout and driver skill I have seen those engines running extremely stable at 160ºC.

Dear all i have heard alot of bad press about novarossi cermics going bad very easily.

I have a .12PT and replaced the ceramic rear bearing after around 8 litres and bearing still looks great. Mind you i threat my engines with great care and i always pre-heat.

How many gallons are needed to make the break-in of 35plus21? After 1 gallon, the engine does not rise of turns and the temperature is too high.
It may be that the engine is not broken yet?

Hi,
I have a Novarex engine, it late 80's it's a Novarex 350-3port. Can someone help me for a replacement piston and sleeves. Or what model in the current Novarossi engine is suitable replacement for it. i'll post a picture soon.
Thank you all.