How hot is too hot?

[GregR1]

so i'm riding my bike around, and i notice that the right foot is a wee bit more toasty warm than the left foot. so i flip the gauges over to coolant temp, and i notice that it's running a bit on the warm side - around 85 C [185 F] during normal riding, and climbs to 105 C [221 F] when stopped.

now, the reservoir is full, the fans come on, but is that kinda hot? when i was riding it around earlier in the spring, it was 70 C [158 F] on the road when going at a decent clip of 100km/h [65 mph].

can you guys flip on your temp gauges and let me know what you're reading? if it's around the same, i'll leave it alone, but if mine's running kinda hot, i'll have to start flushing stuff.

[Rockhead]

Beats the hell out of me what the operating temp is. If it bothers you that much wrap insulated heat shield around your right foot.

[Clint]

That's just fine, Greg. What did you expect with all that burning?

[Ext1jdh]

Come on, ya wimp. Suck it up! Be like Burt Munro - you gotta take a little heat to be fast!

[omegajim]

I think you guys missed one small point; thermostats are usually in the 190 F area, so running at temp will be around 190 F on the freeway, and a bit hotter in stop and go.

As a sidenote, when the thermostat goes bad, it won't get up to operating temp. on colder days. Being Ottawa, that's most days.

[Don M50limited]

when the thermostat goes bad, it won't get up to operating temp. on colder days. Being Ottawa, that's most days.

Actually that'd more likely be opposite, bad thermostats tend not to open and allow any circulation therefore overheat. Stuck open (or running without a thermostat) would allow too much circulation causing it to not get up to normal operating temp.

[Clint]

They're designed to fail open, Don. Can you imagine how many ruined engines there'd be otherwise? How many drivers do you know who actually have it on their calendar to check the thermostat? Doesn't happen.

Jim, even with an closed thermostat it's possible that enough air cooling takes place to keep the temp as low as Greg says. My Bandit often runs that low in cooler weather. They're relatively small engines with lots of air exposure, unlike a car engine, which is somewhat trapped in a confined space.

[Oaf]

I rode an Aprilia Tuono 1000 at the bike show this weekend. When we stopped the temp guage showed 100 C. As long as the temp doesn't keep climbing I think you're OK.

P.S. That Tuono is a sexy beast and fun to ride.

[intimid8er]

Greg...

You answered your own question. Before, it was spring time...........now it's warmer.......

That said, start riding somewhere other than the parking lot!

[Don M50limited]

Originally Posted by RowdyRed94

They're designed to fail open, Don. Can you imagine how many ruined engines there'd be otherwise? How many drivers do you know who actually have it on their calendar to check the thermostat? Doesn't happen.

Oops, there's my lesson learned for the day. That's actually makes good sense as opposed to the way I've always known it for cars. Good to know....thanks

[GregR1]

hmm, true, it was spring earlier, but i would have thought that the bike would run a bit cooler nonetheless. entirely possible that the 30F difference in coolant temps actually matches up with the 30F difference in ambient temperatures (thermo classes slip me now, so i'm not sure if that's to be expected).


hehehe! actually, i've not ridden on a parking lot since my MSF-type course back in mid-april. i keep meaning to find a big empty lot here and do some practice, but lately it's either raining like mad or people suck up all the available space when they go shopping.