I cannot actually pin point why the engine is overheating. Just guessing here but I'm sure you already know that on a hot day, you need to lean the needles to maintain correct AFR because of less oxygen per volume of air. So that would explain the high fuel consumption...

As for the overheating part, I'd like to know what type of track did you run the engine? Technical or high speed? What plug number did you run? High speed would prefer colder plug like 7TF. Shorter technical tracks you could live with a no. 6. Wrong plug would make the engine overheat and make for higher fuel consumption. But my guess is you're using a hot plug on a hot day which would make fuel consumption high as well as overheating the engine.

Was the car overgeared? Did the engine rev at the top end a lot or were you at 0 to 50% of the throttle most of the time? How was the idle? Rich and difficult to start in the beginning or the idle coming in high after a few rounds?

If the engine revved a lot at top end RPM, then your HSN needle would have been too lean which made the car overheat this time and not the last time previous. If the engine was at mostly 0 to 50% throttle on the track, then your low end would have been too lean to overheat your engine. My 2 cents...

r u referring to JP FX series ( blue head, black crankcase ) ? JP FX is latest one.

No I mean the purple head versions

Hi

The RS or the NS version?

If NS JP it should have RACE and NS3

If RS JP it should have RACE and S3 writen on the purple head

It just has RACE S3 on the head

That is the RS JP

does it have the JPracing name etched on the head aswell?

I realise this but I am after a comparison with the new JP's.

The internals of mine look mighty fine.
I will completely pull it down and clean it to remove any metal shavings etc and reassemble ready for run in

Yes i know you are after a comparison but first we need to know what version it is.

It depends on what size track you race on

On a larger track you wont be able to have the same top end speed as with the NS, X12 and FX series JPs.

So does the S3 have more torque or just not rev as high?
What is durabilty like ?

It has less revs than the newer versions.

Don’t get me wrong the smaller-medium track I race on they are just as quick cause the straight is not long enough for the newer JP versions to reach there optimum speed.

Durability is great will last a long time if you take the run in stage carefully and don’t rush it.

Those JP actually novarossi base engines. Durability is good especially if you maintain it periodically ( engine cleaning and proper operating temp. )

All JP engines, past and current, begin life at the Novarossi factory.

if any one is interested in jpfx motors try pdl racing thats where i got my fx21r-01 at $800 bucks thats with break in and dyno

Does anyone know where i can order the ceramic bearing that came with the JP FX? [.12]...Not BOCA please, they don't fit well onto the crankshaft.

Thanx.