X80 Heat Question

I've been breaking-in a new X80 engine for the past two weeks. I have it on a 29"er with a 56T sprocket. I have an NT Speed with a 70 jet, needle at the richest setting, intake ported and right against jug, plus a 6 plug. Running a 25:1 mix of Lucas semi-synth with 20% castor. @ sea level, and ambient's been about 32F/0C. Head has been showing a consistent 360F neighborhood on flats, and around 480F after short moderate hill climbs. Have seen just over 500F (!!!) @ plug after a couple of steeper climbs ("only" about 410F on rest of head). Engine is BLACK, and I use an IR gun to monitor temp. I have verified that there are no air-leaks. Plug chop shows medium gray ashy tip; head/piston inspection shows black piston-top, slick shiny cylinder/piston skirt. Bottom-end clean and oily. My cargo and I weigh over 300#. Engine runs great' and I hav no performance complaints, I just dread seizing a good engine. I'd be more comfortable knowing the engine's cooler and the plug is chocolatey. I suspect I should try larger jets, but should I be _urgently_ concerned? Am I already overly concerned? I've been putting about 30 miles a day on it. I have a modded stock exhaust (removed baffle/cat and replaced with a Chore Boy...better than stock flow). Actually receiving a Voodoo X pipe today, hoping it may improve temp as well as performance.

Thoughts and/or advice please! I treat engines like puppies; I'd hate to realize I was abusing one.

Thanks BornToFli,

So I installed the Voodoo expansion pipe and am now out touring (getting a few pints). I am quite pleased with its performance so far; at a regular checkpoint where I'd seen 480F (top of steep hill). Now @ 400F, and the bike definitely climbed much faster. After a long flat where I used to see 380F, I saw 300F tonight. I'm also seeing better throttle-response at 3/4ths, although there is some 4-stroking before that. Oddly enough, this is after readjusting the pin to the middle-slot, so the mid-range delivery's leaner than before. Will continue to tune and update.

P.S.: For the record, I drilled the stock 0.70mm jet out to a #69 (~0.75mm).

So, the night I installed the new pipe, I found its affect on performance to be supurb. I did find out the hard way that you really need to torque down the connector on the Voodoo between the pipe and expansion-chamber; twice the vibrations and heat caused the coupling to disconnect. Fortunately I didn't loose its circular gasket. I suspct that the new vibration-signature imparted on the system by the new exhaust assembly contributed to my rear mount studs shearing that night only a few blocks from home. I was lucky as I was returning from a distance of about 10-miles. I got the broken studs out with a Dremel and a flat-head, but that's another thread.

Anyway, I took time yesterday tearing-down my build after replacing the studs, and made sure the new x-pipe was installed properly, and that my engine's mount-studs were happily seated and tourqued. I used some ATV to mock anti-vibration padding.

I've been out and about today with the new exhaust, and although I know I'm still running lean (richest needle setting, 75 jet), head temperature has shown a considerable reduction from my modded stock exhaust. The reason I've been running a 56T sprocket recently is two-fold: I went from a 26" to a 29", AND I've been nursing a broken leg, thus my pedalling abilities have been severely compromised. I spent this afternoon tacking some hills I've been finding shallower detours around previously. I was very happy that my bike was able to take them now without hesitation, nor requiring my feeble attempts at assistance with pedaling. BONUS: head temperature is way down. One hill where I'd see 480F showed 340F today AND it took it much faster.

I still need to rejet, but I'm sold on the Voodoo pipe; it's worth every penny.

Me too...literally on the Long Island Sound...guess I'm just a fat bastard; can't change the laws of physics!