Chief Running Hot?

[Scott Curtis]

I rode my 1946 Chief today in 85 degree heat for 50 miles. I have owned the bike for 3 months. The bike seemed to be running hot. In fact the gas in the right gas tank seemed close to a boil. Is this common for these old Indians. I realize with the oil in the tank and setting above the exhaust pipes would be cause for that tank to be hotter than the left side. Any comments will be appreciated!

[pisten-bully]

I rode my 1946 Chief today in 85 degree heat for 50 miles. I have owned the bike for 3 months. The bike seemed to be running hot. In fact the gas in the right gas tank seemed close to a boil. Is this common for these old Indians. I realize with the oil in the tank and setting above the exhaust pipes would be cause for that tank to be hotter than the left side. Any comments will be appreciated!

Agree that does seem hot, though difficult to determine without seeing it boil or somehow measuring the temp. Only time I worry about it is sitting at a stoplight or behind a construction flagman after slow running and with those higher ambient temperatures. Maybe pull the plugs some time to see if you're running lean and or check timing again to see if you're too advanced. Maybe even a manifold leak leaning things out?

Got any pictures of your Chief?

[T. Cotten]

Scott!

Flattys run a hundred degrees higher than an OHV by nature, as it is their optimum for performance.

Still, keeping the rest of the hardware cool is certainly an issue!
Are there other heat signatures, such as unusual discoloration of the exhaust pipes?

You must observe for us, as otherwise we are just conjuring...

...Cotten

[Skirted]

Hi Scott,
Fresh engine rebuild? Or well worn in? What oil are you running? Have you accurately set the timing?
Hot is a relative term with no one there in person with experience to compare. If your ride was mostly at speed and not a lot of stop and go there shouldn't be any concerns with running too hot at 85 deg ambient. Sure mine gets hot in 85 degree temps in stop and go riding but only to the discomfort of me and it doesn't cause any concerning symptoms on the bike. If something isn't right causing abnormal engine temp, I'd think you would have noticed even at 75 degrees.

[Scott Curtis]

I have only owned the bike for 3 months and the guy I bought it from did not know much about the bike. (he didn't know the bike had the 4 speed tranny) By looking at the motor it seems pretty fresh. In fact it didn't look like it had hardly been ridden. It is very tight no oil leaks what so ever. I do know the following:

The bottom end was rebuilt using S & S Fly wheels
It has been converted to 12 volts
It has the 4 speed tranny
It has an electronic ignition
I am running Valvoline VR 1 50 weight oil.

Today I put a little lead additive in the gas tanks and turned out the high speed needle 1/4 turn. The bike ran cooler although it was 10 degrees cooler (75 degrees VS 85 degrees) A well versed Indian guy set the timing using a timing light (discovered the S & S flywheels) so I know that is good. Someone else suggested the lead additive which I would not have thought of. Any ways..... I feel I am headed in the right direction.

[banjomike]

I saw this happen years ago when the person had the spark advance set retarded. The gas was boiling. He had run it this way for 25 miles. BANJOMIKE

[Yellow53Chief]

Hi,
banjomike makes a good point. Running an engine retarded will overheat it. Because your engine has S&S flywheels in it, there might be some confusion concerning the timing marks. Some aftermarket flywheels are marked for front and rear cylinder timing, as well as Top Dead Centers. Luckily, the crankpin nut can be seen through the timing hole, and its location can be used as a reference to locate the front cylinder Top Dead Center (TDC) mark and front cylinder timing mark. Find the crankpin nut while looking through the timing hole. The front cylinder TDC mark will be approximately 1 1/2" to the right of the nut - along the rim of the flywheel. The front cylinder timing mark will be approximately 7/8" to the left of the nut - along the rim of the flywheel. An Indian engine is typically timed to the front cylinder (around 1944 onward, but the process can be used on any twin with a timing hole). The timing is done with the distributor fully advanced, and the narrow lobe of the distributor should open the points when the timing mark appears in the timing hole. When looking at the left flywheel, it turns in a counterclockwise direction. When looking through the timing hole, the first thing seen will be the timing mark, then the crankpin nut, and then the TDC mark; the crankpin nut might be difficult to see, but can usually be seen looking down into the timing hole. The photo below is an original Indian flywheel assembly, but the relative position of the marks would be the same on aftermarket flywheels. The closer your timing is to being correct; the better the engine will run in all respects.

Timing marks on the rim of the flywheel by the crankpin nut.jpg

[Scott Curtis]

Thanks Banjomike and Yellow53 Chief for your comments. I will share them with the mechanic who timed the bike although I have a lot of confidence in him. He has a 46 Chief himself and set the timing without any hesitation after he determined the electronic ignition and the aftermarket flywheels. I will confirm the timing is properly set.

[Yellow53Chief]

Hi,
Regardless of the flywheel type or ignition system used, the vintage Indian V-twin's timing is generally set to fire the front cylinder, with the advance/retard mechanism in the fully advanced position when the timing mark is in the middle of the crankcase hole, which is directly below the carburetor brace. The advance in degrees will work out to be around 30-35 degrees, with the front piston being approximately 3/8" Before Top Dead Center (BTDC). Final tuning for timing will usually be done in conjunction with road work - where maximum performance can be evaluated. With the timing set as mentioned above (fully advanced), the fully retarded timing will usually be Top Dead Center (TDC) or later. With TDC or later timing when fully retarded, the bike will not kick back when trying to start the engine.

[T. Cotten]

Scott!

With all due respect to your builder,
Heat can come from friction, inaccurate timing, etc., but most often from a lean mixture.
And frankly, that often has nothing to do with the carburetor. Arbitrarily over-enrichening can only mask greater evil.

Did your builder, or you yourself, bubble-test the manifold assembly?

Had to ask... sorry,...

...Cotten

[fillibuster]

I was waiting for it:
How hot is hot? These were my gauges, read mostly with a sidecar, on Colorado mountains, on a long haul to Davenport, in 85+ degree heat, riding like it hard.
Your right leg gets pretty hot, uncomfortably so. This from riding at speed+.
Little "geysers" spout from the old gas caps, the ones with the little hole in the middle.
After power loss and parking, removing the air filter to see why it seems flooded you see gas percolating up through the main nozzle. Park it in the shade, drain the bowl, remove and replace caps, have a soda, maybe talk your payload into riding with the sweeper (if you dare!).
Seems to me that lean mix was always accompanied by a persistent ping, like you get when running out of gas. The hot leg always occurred during hard work, when the bike had previously run just fine, and ran just fine after cooling off.