Shovelhead Temperature Questions

[confab]

After you ride for a few hours and include some higher speeds.. What would a normal oil temperature be? Would would a high temperature be?

Detonation is detectable just like in a car, right? The hammering sound.

I never get a pop on decel. Nothing to indicate a lean condition. Always run premium fuel.

Is there anything special you do to keep your bike cool? I have the lockheart cooler installed.

Thoughts on timing considerations?

[JBinNC]

In HOT weather, July and August, I've seen 250 degrees on the oil tank thermometer. A lot of people freak out at that, but I don't see a problem. Stroked FLH, no oil cooler. The oil does need to get into the 200 degree range to boil off water contaminants.

Detonation is NOT detectable except by looking for signs on the plugs. All four stroke engines are the same in this respect. You can of course hear spark knock, but that is NOT detonation. Running premium fuel is cheap insurance, especially in hot weather. Shovel chambers are lazy and prone to detonation, so most cams close the intake valve fairly late, compared to an evo or twinkie. Big cranking compression numbers are a MISTAKE on shovels because of the danger of detonation. Tune a little on the fat side, your mileage will suffer but your motor will live.

The stock 35 degree advance timing is good for stock or mild motors. Increasing the low rpm timing will usually help a mild motor with a cam. Dual plugs may allow a reduction in advance timing of 3 or 4 degrees, MAYBE.

My 2c, take it for what it's worth,
Jim

[Fetch]

80" shovel with an Andrews J cam, a slightly rich mixture and 105lbs compression (cold) . It seems to run consistently 200 +- 10 degrees .

[confab]

Thanks.. Do they behave differently when full hot?

[JBinNC]

Plug looks typical. Do a pic with the side strap visible.

Jim

[confab]

I re-gapped this because I dropped it when it was removed.

[JBinNC]

Color change is pretty far down the strap, so watch your timing, your full advance timing may be a little high. Do you see a fuel ring on the porcelain, and if so, where is it?

Jim

[confab]

Interesting question.. I don't know what a fuel ring is?

I assume you're talking about a distinct color change in the porcelain, and that would be about even with the shell of the plug.

What are the dynamics you are looking at the the strap and the fuel ring?

[JBinNC]

Fuel ring is the dark ring on the porcelain. Two stroke, four stroke, gasoline, ethanol, methanol, or nitro, it's gotta be there or you are too lean. The closer to the tip, the richer, the closer to the base, the leaner. No ring and you are TOO LEAN. On a shovel, half or two thirds of the way down is good. Evos, two thirds or right at the base is good. If you are checking these plugs after just ridin' around, you are getting mostly intermediate jet check. Full throttle passes with a chop will give you main jet reading.

The strap is a little harder, but I was taught to look for a color change at the turn, for a rough check on the timing. Color change near the weld like yours may mean a little too much advance, but that can also be affected by the mix.

Jim

[rockman96]

96" big bore stroker, runs 220F - 230F in the heat of the summer.

[confab]

Thanks all.. Very useful information.

Particularly this advanced plug reading.

I had no idea it was that detailed.

[JBinNC]

Thanks all.. Very useful information.

Particularly this advanced plug reading.

I had no idea it was that detailed.

Just scratchin' th' surface. I only know enough to keep myself out of trouble (usually).

Jim