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silverbird1100

Cooler running thermostat?

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If you can match it to an existing type of auto thermostat, you may find one in a lower temperature range.

 

I'm not sure if it matters, but I had constant boil over issues because the thermostat went bad and remained open.  So, it messed with how the coolant regulated its temperature.  Replacing it put it back to normal.

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Thermostats can fail, but it is a rare occurrence, without going into a protracted explanation about thermodynamics simply replace it with a new honda  Honda Part.

If your bike is overheating , Ck the thermostatically fan for proper operation, its relay and coolant sensor.  Have you recently replaced the coolant ?

Running old coolant can cause problems, long shelf life can cause it to " glop up " become to thick to circulate freely, causing overheating, never use undiluted antifreeze,it to can cause overheating. If it were me I would flush the entire system with distilled water, twice.......this can be a tedious process, when you take the time to burp the system for trapped air .

refill with Honda antifreeze properly diluted  50/50  with" water wetter" and distilled water.

If you are still overheating at this point, you have other problems than a thermostat.

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What problem are you trying to solve?

 

99% sure a 1998 Civic thermostat would fit, and you can probably get different temps.  Caution:  Going to a "cooler" thermostat could actually make things worse.  This isn't as straightforward as you seem to be assuming.

 

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I'm just wondering why it doesn't fully open until 204F.  Wouldn't it run cooler to fully open vs partially open at 177F?  

 

 

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My bike operates at 176 to 180 degrees .  it has since new.

Temps went up about 2 degrees when I switched from dino oil to synthetic.  But still below 180, on days that are cool enough for the thermostat to regulate.  If air temp is too high for the cooling system, then you will be running hotter, thermostat or no.

 

Coolant change with Honda coolant won't hurt, and may help.  Stay away from DEX.

Evans waterless will prevent over boiling, but heat has to leave the bike, no matter what coolant.

 

Many, many years ago , there was a post showing a waterpump that had been destroyed by silicate based coolant.  Phillip?   

 

I have had car flow rates tested at a shop years ago. It was done with a in line flow meter.

I don't know if there is a flow meter for bikes.

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41 minutes ago, silverbird1100 said:

I'm just wondering why it doesn't fully open until 204F.  Wouldn't it run cooler to fully open vs partially open at 177F?  

 

 

 

What is "run cooler?"  This reminds me of a conversation with a friend about his Jeep.  He asked if mine overheated all the time in summer, and I said no.  He asked what I did to prevent it.  I was confused.  He thought that running 205-210 was "overheating," when it's perfectly safe for it to go above 240.

 

What temperature, exactly, concerns you?

 

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It's probably the consistently high reading temp on the gauge.  Down here in the deep south it has gotten into the red on multiple occasions when coming back in from a pass at the dragstrip.  You just can't dissipate all the heat you're generating in 1/8th of a mile at nearly WOT under full acceleration stress.  I always had two high velocity fans in the pits and let the bike sit slightly off idle until temps cooled off.  It never hurt anything but it is damn sure unnerving to say the least.  You sit in traffic down here and it regularly dances on the high end of the gauge like it's going to touch red but never does.  Considering pavement temps reach 140 or so down here and you're surrounded by cars pumping out heat it shouldn't surprise me but I still to this day think that can't be good to run that hot. 

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Once the thermostat is open, it's open.  An engine that runs at 220 will not run cooler if you shove a 160 thermostat into it.  So if you hate that your bike reaches 204 because the thermostat isn't fully open could indeed run cooler with one that opens sooner, but 204 isn't an issue.

 

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It's important to remember that the thermostats job is not to limit the max heat of the. Coolant.

 

It's job is to get the coolant to the correct operating temperature as fast as possible.

Correct temperature reduces wear, increases fuel economy, reduces emmision,  etc.  

But during the summer heat, the engine is at temperature quickly, and rising higher, if the cooling system can't keep up.

 

Where the thermostat helps is when the outside temperatures are are low.  The thermostat bypasses the radiator, allowing the engine to warm quicker.

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Exactly, well said.

 

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An open thermostat like Zero supposedly had won't cause boiling.  If it's completely stuck at a small opening then it might not flow enough at high RPM/load to cool and cause overheating.

 

A thermostat doesn't fully open at its rated temperature, that's where it starts to open and won't fully open 'till it gets hotter.  A lower temp thermostat will lower the operating temp IF there's enough heat exchange happening at the radiator; enough air flow and enough coolant flow.

 

I don't think the bird's hot tempered nature is due to the thermostat limiting coolant flow, it seems to be because of limited air flow through the radiator, and the 'problem' isn't limited to the bird.  Mine will run cooler at highway speed than street speed even tho there's more heat being created, this tells me it's probably an airflow issue.

 

If your bike is running 204 all the time something's wrong, if it's only doing that at relatively low speeds or when hot-rodding it's pretty normal.  Mine occasionally went over 220 on hot days stuck in traffic, highway cruising it would do 180ish.  I don't think there's any way to make a thermostat fully open right at or near the rated temp, and you wouldn't want it to.  If it did the temp would constantly be jumping up & down any time there was enough flow through the radiator to dissipate the heat.

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On 8/6/2019 at 10:10 PM, redxxrdr said:

 

Many, many years ago , there was a post showing a waterpump that had been destroyed by silicate based coolant.  Phillip?   

 

I had the water pump on my '97 fail in about 2008 - all the impeller blades had broken off.

 

Since then I had the replacement pump seals fail... current one seems ok and the bike is on 155,000 km -ish

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11 hours ago, brianmacza said:

all the impeller blades had broken off.

 

How the fuck did that happen?!?

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On 8/6/2019 at 4:10 PM, redxxrdr said:

My bike operates at 176 to 180 degrees .  it has since new.

Temps went up about 2 degrees when I switched from dino oil to synthetic.  But still below 180, on days that are cool enough for the thermostat to regulate.  If air temp is too high for the cooling system, then you will be running hotter, thermostat or no.

 

Coolant change with Honda coolant won't hurt, and may help.  Stay away from DEX.

Evans waterless will prevent over boiling, but heat has to leave the bike, no matter what coolant.

 

Many, many years ago , there was a post showing a waterpump that had been destroyed by silicate based coolant.  Phillip?   

 

I have had car flow rates tested at a shop years ago. It was done with a in line flow meter.

I don't know if there is a flow meter for bikes.

 

Nope, bot me.

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On 8/6/2019 at 4:10 PM, redxxrdr said:

Temps went up about 2 degrees when I switched from dino oil to synthetic.

Since no one else asked, why would temps go up with oil that supposedly has less friction?  The same weight of oil?

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2 hours ago, blackhawkxx said:

Since no one else asked, why would temps go up with oil that supposedly has less friction?  The same weight of oil?

I have no and answer.

I went from my first oil (dino) after break in to the same weight in Mobile 1.

Outside temps in the 60's.

Indicated water temps went from 176 to 178 degrees and stayed.  

It has never dropped back to 176, and has always stayed at 178 with proper cool air cooling.

 

I have rotated through Mobil 1, hotel t6, and royal purple with no change.

The issue should be thermostat related, but I didn't change coolant for thousands of miles .

 

Strange. But I don't worry about 2 degrees , compared to my perceived quality of synthetic oil.

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It was during break in so it could have been things changing about the machine or your use of it.  If you were to switch back and the temp dropped it would indicate that either there's a lot less friction, unlikely, or that dino has better heat dissipation ability which is possible.  Syn is supposed to retain its viscosity better as temperature goes up and a thicker oil will run hotter.

 

My bike needs an oil change, I'm gonna try to do a baseline cruising temp test before/after just to see if anything happens, but I don't expect it to.

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15 hours ago, superhawk996 said:

How the fuck did that happen?!?

 

We need a professional root cause analysis here.

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15 hours ago, superhawk996 said:

How the fuck did that happen?!?

Dunno... normal antifreeze mix and the engine started running HOT and none of the diagnostics found anything - even flow tested the rad. Pulled the water pump and found most of it missing

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Did you find the pieces?  I can't imagine them breaking without some obvious damage, only other explanation would be that they rotted away.  Or it had a pretty serious manufacturing flaw.

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The bits were stuck in one of the hoses... never got enough bits to make me think I got them all though

 

.

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