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bykemike

Thermostat issue?

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41 degrees F  at my house this morning, my 95 starts right up and a couple of miles later I am rolling down a local road at 80+, all good, runs like a champ as usual

about 12 miles later I notice the temp needle still hasn't come off the peg, I stopped for a school zone and it climbs up a needle width and then drops right back

down when I start to speed up.

 

My first guess is thermostat, second guess is temp gauge.

 

Any thoughts from the more experienced owners?

 

Thanks

 

 

DSC_0916.JPG

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In the 19 years I had her, redslut's thermometer would hardly move. Most of the time. Only on say 26C+ days and giving it some welly/ride stop go traffic would it move over the half mark.

The 4th gens are known for this and I never worried.

Some added a resistor? to make it respond better I recall.

 

As long as the fan kicks in when needed you ate good to go.  Thermostat testing procedure is in the manual i think (never bothered myself)

 

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Ok Dutch, thanks for that.  It ran as if it was up to temp so I wasn't going to jump right in.  After my last Ducati, (999) which spent most of its time over 230 degrees and saying it was, this is a big change to be able to idle in traffic at OAT of 95 degrees and not be concerned.

 

Duc sure was pretty though

 

Thanks!!

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My '90 was like this when I bought it - actually I am not 100% positive the needle moved that single needle width or not, but I think it did. Anyway, consensus was to replace the temp sender - that it was a common issue. Sure, enough, that fixed it. Normal readings are now way below half range at about 25-30%.

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Mine was doing the same. I was doing other stuff so I drained the coolant, flushed with water, changed the thermostat, pulled and wiped off the sensors. After I refilled the system I taped the temp sensor that came with my multimeter to the hose on the right side of the bike. It came up to 186 or so and sat there, the fan would kick on and off.

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Great idea, I will do just that.  I have always thought this bike was running real cold because of the gauge but it runs like a fully warmed up bike

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Thought I would jump in here; on my '97 the temp gauge needle is normally about a quarter up when moving at speed, moves further upward when in traffic and the fans come on.  In other words, the needle moves  a lot and I think reflects the coolant temp accurately.  This is the end of my 3rd summer with my VFR and temp gauge has always been this way.  Of course when riding at air temps of 95+ F...the coolant does have to work.

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All VFR750's are like this. It's not until you've been riding it hard for a while then end up in London city center style traffic that it gets to the half way mark and the fan kicks in. I wasted a load of money on my first VFR750 thinking the thermostat was an issue...nope, wasn't, just the way the bike is.

 

I honestly reckon we could get rid of the oil cooler and there'd be no issue. Might run mine for a season without one and see how it goes.

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41 degrees F  at my house this morning, my 95 starts right up and a couple of miles later I am rolling down a local road at 80+, all good, runs like a champ as usual
about 12 miles later I notice the temp needle still hasn't come off the peg, I stopped for a school zone and it climbs up a needle width and then drops right back
down when I start to speed up.
 
My first guess is thermostat, second guess is temp gauge.
 
Any thoughts from the more experienced owners?
 
Thanks
 
 
DSC_0916.thumb.JPG.cd521ec403bffe01e05d692d56e6e030.JPG
Had the same issue on both my 97 and 02 VFRs and my 94 Celica. All had thermostat stuck open which will cause the engine to run rich.

Sent from my HTC 10 using Tapatalk

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Honda thermostats like to stick open.  

 

Ciao,

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If it's the original thermostat, just replace it.  Should be a piece of cake.  

 

Your coolant temp should be around 174 degrees in normal riding and cool temperatures.  On really hot days it may get to 185-190.  220 degrees idling in traffic with fans on.

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I think there's a bit of exaggeration going on here. The VFR's ALL show a low needle rise, my 94 barely breaks an 8th in normal riding but hits half way on a summers day in stop start London traffic on my commute. To comfortably get at the thermostat, it's a carb off job along with a coolant replacement. I'd be very surprised if it's that and not just the normal behaviour of the engine temp indicator.

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I opened the bike up yesterday and looked at what it would entail to change the t stat, thought about how well it runs and thought "screw this" there will be a time I have more apart and I will get to it but for now I would rather ride. this is our season down here, right now!

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34 minutes ago, 750 said:

I think there's a bit of exaggeration going on here. The VFR's ALL show a low needle rise, my 94 barely breaks an 8th in normal riding but hits half way on a summers day in stop start London traffic on my commute. To comfortably get at the thermostat, it's a carb off job along with a coolant replacement. I'd be very surprised if it's that and not just the normal behaviour of the engine temp indicator.

 

I concur. I said my '90 reads on average 25-30% after the new sender. I remember now that when I bought it the needle didn't move at all. After the last couple of rides this past week, mine does indeed stay at about 1/8th on the gauge. Oh yeah, they also all smell rich at idle. Normal.

 

Cheers,

Glenn

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Thanks Glenn, that slightly rich smell bugs me but less and less.  This bike runs so good, never misses a beat from idle to red line, every time smooth as silk, 200 + miles per tank.

 

  I would rather touch nothing unless it needs it.

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49 minutes ago, bykemike said:

Thanks Glenn, that slightly rich smell bugs me but less and less.  This bike runs so good, never misses a beat from idle to red line, every time smooth as silk, 200 + miles per tank.

 

  I would rather touch nothing unless it needs it.

 

:fing02: There ya go. The only touching it needs now is your ass touching the seat!

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