Apher
New member
My Dad picked up an 2000 Yamaha Mountain Max with some mild porting and triple pipes that has a three panel EGT on it. He was told to watch the exhaust temp and not to push it over 1400. The gauge starts flashing and beeping when it reaches 1350. Wile First ride out on it the other day. Going up the trail he had not problems with exhaust temps. But when we go up to fresh snow and hills it was constantly jumping up to 1400. We would sit and let it cool down for a wile then fire it up. Let it warm up for a minute and hit a hill that was 200 yards long and it would be flashing at him.
All this time I am riding with him on my Mountain Max that I have put a digital water temp gauge on. When he was hitting 1400 my sled is only saying 100 degrees. Not even close to the 180 overheat mark.
Neither of us have had any experience with this type of equipment. Can some one help advise us on what temp we need to be watching for. If we can not get but one or two hits on a hill before we are overheating the exhaust. This is not going to be fun.
We are wondering if the jetting is so lean that it is overheating? It has some weird wire tip spark plugs in it so getting a plug reading for jetting is not going to work.
The original owner did not ride it a lot. When we would ride with him he would always hit a hill once maybe twice and then sit for a wile. Then hit it again. Then sit. We always wondered why. But now we are stating to think that he had it jetted so lean trying to get every HP he could that it was getting hot. So he would let it cool between runs.
All this time I am riding with him on my Mountain Max that I have put a digital water temp gauge on. When he was hitting 1400 my sled is only saying 100 degrees. Not even close to the 180 overheat mark.
Neither of us have had any experience with this type of equipment. Can some one help advise us on what temp we need to be watching for. If we can not get but one or two hits on a hill before we are overheating the exhaust. This is not going to be fun.
We are wondering if the jetting is so lean that it is overheating? It has some weird wire tip spark plugs in it so getting a plug reading for jetting is not going to work.
The original owner did not ride it a lot. When we would ride with him he would always hit a hill once maybe twice and then sit for a wile. Then hit it again. Then sit. We always wondered why. But now we are stating to think that he had it jetted so lean trying to get every HP he could that it was getting hot. So he would let it cool between runs.
Backwoods M Max
New member
What altitude did the sled come from vs where are you riding it now? Coolant temp will not represent egt's. The egt temp is what the piston is seeing after combustion right before the port opens and spills that fireball out into the pipe for the pyrometer to read. The temps are being caused by a lean condition. Not enough fuel to burn all the way through the power stroke. I would jet up a size and go ride again.
roudyroy1
Active member
those are exhaust gas temps, what was he running for thottle? mid range or pinned when the egt sounded? i would bump a main and up the needle