Pyrometer 101, School Me !

[Rprecision]

I have never had a machine with a pyrometer before. I just purchased a 04 RMK 800 which has one.

Now, help me understand the fundementals of a pyro, not so much of how it works rather what temps are normal, dangerous, etc.

I have serched this forum in and out, google, SLP and have yet to find any information

The previous owner told me that if it hits 1200 degrees, gaskets would be trashed. He really didnt have much more information.

Thanks

 

[SLEDIOT]

What mods are done to the machine and what elevations are U at. 1200 is safe on most machines. I wo'nt run my efi cats at more than 1250. Holding at these temps for prolonged periods might be hard on some things but its not a major danger zone.

 

[bigbull]

Search for Fbomb's information on this. It is the best on the forum.
BB

 

[bushy]

Try a search on EGT (exhaust gas temperature) and you'll find more results.

 

[Scott]

1200 is safe on most machines.

And don't take this to mean that is what YOU should run. EVERY SLED and riding area is different. Sure, aluminum is the same, it melts at 1500 degrees (or whatever it is), but that is the piston and cyl temp, NOT the EGT reading.

Here is what you do.....
UN HOOK or put TAPE over your PYRO gauge and don't even think about what numbers it shows until.......you have the piston wash and plug readings dialed in for that temp, humidity and elevation. THEN whatever your pyros read at that piston/plug reading...THAT is your optimal pyro numbers range.

So when the factors (conditions) change, ie elevation or humidity or temperature, you have to do it all over again to make sure you pistons and plug readings are correct before you trust the pyro numbers. After a season getting to learn that sled from cold winter to warm days to late spring or summer, you'll know you your engine behaves with those 3 factors that I stated.

 

[kennyblatz]

i would second scott on this. you really want to stick to basics, a lean motor could melt at 1200-1250 a rich motor could run all day showing temps up to 14-1500 cause it's reading a flame coming out of the exaust and not a true air temp.

 

[Rprecision]

What mods are done to the machine and what elevations are U at. 1200 is safe on most machines. I wo'nt run my efi cats at more than 1250. Holding at these temps for prolonged periods might be hard on some things but its not a major danger zone.

Stock engine, SLP pipes, can and air box. Running at 10,000' to around 11,500' sometimes a touch more.

Scottt, Thanks for the advise, that makes sense. When the snow flies I will get it going and see whats what.

 

[JROD]

Scott hit the nail on the head but....

You also have to know that kennyblatz is right as well. I've hit 1400 on my sled at a few rare times and not had any problems but I try not to get over 1300. You can also be so lean that you'll only hit 900-1000 degrees because you do not have enough fuel to make heat but I've also seen sleds so rich that they'll only hit 900-1000 degrees because they don't have enough air to make heat.

EGT gauges are a tool but NOT A STANDALONE TOOL. You should really learn how to read wash. Sometimes thats almost impossible (like in my Rev) but at least be able to look at your plugs and know what is happening and relate it to the temps on your gauge. Here's a few websites that might be able to help you out.

http://www.smellofdeath.com/lloydy/p...diag_guide.htm

http://www.dansmc.com/Spark_Plugs/Sp...s_catalog.html

http://www.snowtechmagazine.com/arti...e/baseline.php


http://www.dragstuff.com/techarticle...ead-plugs.html

 

[SLEDIOT]

I amvery cautious,.Last season I popped my 700 motor and then on my maiden voyage with the Big Bore I blew a spyder in my primary and ended up in burn down 1km from the truck!! So now I really respect my pyro's and still check my plugs once a ride just to see. Twas a $10,000 season with spare parts and motors..............