Hey all, new to this forum and have been wondering about this question for quite some time. I have a stock 1992 Yamaha Blaster (It's a Pink / White color scheme if that matters). Every single part on this quad is still original OEM parts (With only a top end rebuild and carb rebuild done recently, all OEM parts still). It does puff a bit of smoke which is why I did the top end rebuild so I could replace the piston rings due to low compression; I later found out that my compression tester seems to need something called a Schrader valve which this "cheap" one might not have? I honestly have no clue. Regardless though, it's either due to the crank seals being bad or this it's just natural due to it's 2 stroke nature and age.
The actual question I have is regarding the operating temperature of the head. I have a Trailtech Vapor with the temperature sensor underneath my spark plug. The carb has been "tuned" as well as I can with my limited skills and knowledge but I often see the unit reading upwards of 140C on hot days. I do definitely ride it hard, but upon the top-end rebuild the engine looked surprisingly great with no pits or signs of overheating (This quad used to be street legal and clocked many thousand kilometers for a family security business before retiring in my garage). The machine still has TORS and the stock oil pump so no premix fuel or anything blocked off. What temperatures are safe to ride in as this 140C maximum doesn't seem great. Normal conditions are around 110C - 120C with 130C if I push it hard but nowadays in summer 120 - 130C is the lowest I can get with short cooling periods (with the engine idling since I don't know if turning it off would cause cooling to happen too fast?)
Any information would be appreciated
Edit: just some extra information:
Starts on first kick and runs quite well.
Top speed around 65km/h on dirt/gravel roads.
Maximum RPM around 12,500 - 13,500 (13,500 is the maximum I've ever seen but I don't ever keep the machine pinned to 10,000+)
Smoke I mentioned is white smoke and oil is definitely not milky. After it sat for a few years the oil was milky which in combination with the white smoke made me do a top end rebuild since the gaskets were still 30+ years old. Clutch cover, whatever the other side with kickstart and gears gasket is called, reed and exhaust got new gaskets with the top end rebuild (Head gasket and cylinder gasket sealing it to the bottom end with a new piston, rings and circlips) - The clutch cover gasket was in terrible condition and I would not be surprised if it was the reason for the milky oil due to water.
Runs on standard 93 unleaded petrol with Total Super 2-Stroke Oil and Total 4-Stroke Motor Oil in the bottom end
I believe my compression tester showed around 80psi or less of compression which I doubt is correct based off the units performance. We don't work in PSI here nor do I have any clue what compression it's supposed to have in bar. All I remember is that it's supposed to have 100-120psi correct?
The actual question I have is regarding the operating temperature of the head. I have a Trailtech Vapor with the temperature sensor underneath my spark plug. The carb has been "tuned" as well as I can with my limited skills and knowledge but I often see the unit reading upwards of 140C on hot days. I do definitely ride it hard, but upon the top-end rebuild the engine looked surprisingly great with no pits or signs of overheating (This quad used to be street legal and clocked many thousand kilometers for a family security business before retiring in my garage). The machine still has TORS and the stock oil pump so no premix fuel or anything blocked off. What temperatures are safe to ride in as this 140C maximum doesn't seem great. Normal conditions are around 110C - 120C with 130C if I push it hard but nowadays in summer 120 - 130C is the lowest I can get with short cooling periods (with the engine idling since I don't know if turning it off would cause cooling to happen too fast?)
Any information would be appreciated
Edit: just some extra information:
Starts on first kick and runs quite well.
Top speed around 65km/h on dirt/gravel roads.
Maximum RPM around 12,500 - 13,500 (13,500 is the maximum I've ever seen but I don't ever keep the machine pinned to 10,000+)
Smoke I mentioned is white smoke and oil is definitely not milky. After it sat for a few years the oil was milky which in combination with the white smoke made me do a top end rebuild since the gaskets were still 30+ years old. Clutch cover, whatever the other side with kickstart and gears gasket is called, reed and exhaust got new gaskets with the top end rebuild (Head gasket and cylinder gasket sealing it to the bottom end with a new piston, rings and circlips) - The clutch cover gasket was in terrible condition and I would not be surprised if it was the reason for the milky oil due to water.
Runs on standard 93 unleaded petrol with Total Super 2-Stroke Oil and Total 4-Stroke Motor Oil in the bottom end
I believe my compression tester showed around 80psi or less of compression which I doubt is correct based off the units performance. We don't work in PSI here nor do I have any clue what compression it's supposed to have in bar. All I remember is that it's supposed to have 100-120psi correct?
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