I received a fun thing in the mail yesterday, it is a cylinder head temp guage.  I found it on a website for unltralight aircraft, and at a pretty good price too I think.  The guage and sensor plus shp was $48

If I can get the image over here I will post a pic of it

the guage has the  degree F temp over the degree  C temp scales on the guage.



sensor



I also have an fuel/air mix guage for the exhaust system, but need to get the O2 sensor yet.

Yea, the little wire is about 2' long.

It's the temperature difference between the sparkplug end and the end where it plugs into the gage.  I'd head straight up from the sparkplug under the tank and straight to the bars if that's where you're going to mount it.  and coil it up under the gage to take up the slack.  If you're going to put the gage in a tin can, make sure it can cool off quickly with airflow.  If the can is 40° hotter then ambient it will lower your readings by 40°  And if ambient is 140°, get the hell off the road before you fry!  

I've concidered mounting the veypor to a plate attached to the top of the tree.

Rockin_John wrote on 12/31/69 at 16:00:08:


Cool, Wally World!  I got a better place for you though, on top of the clutch cover about the rear side of the jug, there's a plugged port.  That's directly in the path of the oil.  

Or one of the ports they use for the oil cooler mod.

Another option, any of the bolts on the head cover.  Of course this wouldn't read direct temp, but you'd sure know when it's hot.  

I picked up one of those German oil temp gauges (in Celsius) and have been watching it.  Lately, with temps in the mid and upper 90's (F) and after about 30-40 miles of freeway riding at 70 MPH, the oil temps have been running close to 130° C (that's roughly 266° F).

I'd say that's about right... as my stick on temp gage no longer works.   :'(

I did get a IR spot thermometer, said 180°F in the same area as the oil channel in the clutch cover after a similar run.

Just did my 2nd oilchange at 1400 miles. After a brisk 20 mile ride ( 60 to 75 mph)in 88 degree weather immediatly drained and measured oil temp with oventhermometer as it exited the drain opening. Almost 200 degree (about same as the first) This is the temperature that goes thru the oil pump and it might pick up some more degrees on its way to the lube points. The return oil is always hotter since it picked up heat from cooling and lubricating (friction) So I think that I don't have to worry about overtemp. Granted localized temps will be higher in certain spots. This time put in Mobil 1  15W50 ext performance (easy to get @$5.50)Unlike the other grades of Mobil 1 this 15W50 does not have "energy conserving= friction modifiers) on the label. I have been using Mobil 1 since 1976 (had to buy it on the docks from the distributor since it was not available at the stores yet) and have been using it in every vehicle since  after a break-in period with regular oil to seat the rings.(exept airplane since mobil 1 can not scavange lead in avgas and forms sludge) My car has 150000 and another car has 120000 miles and both run like new. Used it in my Ducati 39000 miles and 3 seasons of road racing and in my Honda 650 interstate for 28000 miles (which I still own) without any clutch/spring replacement or problems. Driven 200 miles on S(avage)40 and clutch works great. Compared stats on 20W50 V twin (harder to find) and regular 15W50. Almost identical on everything (Gravity,Density, Flash point,Viscosity Kinematic cst @ 40 and 100 degree Celcius, Viscosity index etc) and Mobil could not supply a good reason to go with V-twin.( I think they can just charge more).