Go faster

By Stu aka S.Hanson #17 Posted March 8, 2021 I currently run egt on my bikes. I find it is very helpful when riding longer distance in one gear to monitor what exactly is going on and if I should let up on the throttle, rejet, pull over or good to hammer it for sustained riding time. I am also looking to run cht. I use westach gauges. They are analog, dont need an outside power source and easy to set up and has the choice to weld or not weld a bung to your pipe for the egt sensor. https://www.westach.com/product-page/201-ss-ss https://www.pegasusautoracing.com/productdetails.asp?RecID=63 The gauge comes with the wire to connect the gauge to the thermocouple. Its optional if you want the small light that fits in the back. You will also need to buy the thermocouple/sensor. You will have to figure out how and where to mount the gauge. I am making a few that mount under the headset similar to the old rear view mirror mounts. Waiting on the laser cutter guy. I have seen extensive and thorough articles on where to mount the cht ring. Anywhere from under the cylinder head nuts, to under the sparkplug (as its designed for). If you mount under the spark plug slight modification may be necessary. Make sure you get the correct gauge for the temp range (listed) Please note the clamp on exhaust temp sensor i have listed i think is to long. They have a shorter one. Please double check if you order To properly fit the cht sensor that fits under the spark plug, you must make a notch in the cylinder head so the sensor will fit flat under the plug. The modification i made looks a lot worse in the pictures... came out pretty good. You should remove the head to properly attempt. So I just saw this video about the sensor under the spark plug or on top of the plug. He says under or over it reads the same temp. So for everyone who does not want to take the cylinder head off to modify for the sensor, check out the video. I have seen people use a peice of fuel line as the spacer.. jbcollier Posted April 10, 2021

First, he doesn't compare apples to apples. He talks about under/over the plug but he compares over the plug with attached to the side of the head. What you would find if you compared over/under the plug is that over the plug would lag behind the under the plug. Second, he says they both read the same EVENTUALLY. My experience with CHTs is in air cooled VW engines. We put them under the plug. That is where you get the fastest reading of what's going on. Many times, with a little care, I have re-used sensor adaptors when changing plugs. In my experience with CHTs you want to know what is happening NOW, not later. If you're climbing and using the CHT to make sure you don't overheat the engine, what's the point of a "later" reading? Finally, he says you have to remove the head to machine the side pocket for the under the plug sensor adapter. Can't see why. Just cut off the end of an old plug, fill the hole with sealer and then thread that into the spark plug hole to keep out the swarf.

Stu aka S.Hanson #17 Posted April 11, 2021 I agree. I saw an article awhile back. Very extensive and lambretta specific on cht sensor location. They compared temp rise and temp max reading of a sensor under each cylinder head nut, under and over the plug and screwed into on of the head cooling fins. As you say, best, most consistent reading was under the plug.. The lag in reading is more of a gamble the closer to the "edge" of a cylinders performance you get. If you are building a kitted motor or rebuilding one, it is a simple alteration to do to the head wether you currently plan to run cht or not. Just do the job correctly from the start. Dont cut corners!

Stu aka S.Hanson #17 Posted May 1, 2021 Here is my bracket/gauge pod for westach cht/egt. Imagine it w/o the afr gauge wires... On 4/7/2021 at 11:45 AM, Stu aka S.Hanson #17 said: So I just saw this video about the sensor under the spark plug or on top of the plug. He says under or over it reads the same temp. So for everyone who does not want to take the cylinder head off to modify for the sensor, check out the video. I have seen people use a peice of fuel line as the spacer.. Expand Yeah I saw this . Thought it was a great idea! DerekM Posted November 15, 2021 i've finally bit the bullet and order cht guages for a couple of scoots. nice tip for the cht mount as an interim.

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Stu aka S.Hanson #17 Posted September 20

Update/ observations. The danger zone with a static ignition for egt is 1200f. and for cylinder head 425f. At those temps you are actively melting your piston and about to seize or hole your piston. What never seems to be discussed is numbers with a variable ignition. My experience illustrates the need to run both egt and cylinder head temp gauges. I was out on a longer ride this weekend on my ser.1 rapido reedvalve. It has a vape variable and only an egt. My temp when cruising was to high around 1200f +- and when at w.o.t. it was 13 to 1400f. I surmise this occurs because retarded ignition will send more heat into the exhaust, raising your exhaust gauge, but also lowering cylinder temp. My timing is retarding, when I start up it is around 22/21. When I'm at cruising speed its at 18- and when I am at w.o.t. its 16 or less. The numbers still freak me out... Would love to hear others experience with variable ignition and gauge numbers