Suzuki SV650 Riders Forum banner

1 - 13 of 13 Posts

·
Registered
Joined
·
2,737 Posts
Discussion Starter #1
how do you rig up a l.e.d. to come on when the engine is over heating?
 

·
Registered
Joined
·
189 Posts
I may not be qualified to answer this, but you may need a thermocouple sensor to send you a signal/voltage when the temperature is reached. After that, it's pretty simple electrical stuff. I haven't touched electrical stuff since grade 7, so I'm entirely bs'ing off memory.

You can't feed of your dash's temp readout without some advanced low-level computer programming and tapping into the computer and reading bit-code.
 

·
Registered
Joined
·
6,503 Posts
The first generation bikes have exactly what you need. A thermal sensor switch (which would have the correct set point) is threaded into the thermostat housing. The switch is open when the coolant is below set point, closes when the coolant gets too hot. Supply an LED from a source that's hot when the key is on, run the ground from the LED to one side of the thermal sensor, the other wire from the sensor to ground.

I don't know if second generation bikes have a threaded plug where the thermal switch would go (same housing as first generation). If not, you would have to replace the thermostat housing with one from a first gen.

The warning light doesn't light up on start up, so to test it you pull the wire at the thermostat from the LED and ground it. The LED should light up.
 

·
Premium Member
Joined
·
3,729 Posts
... I don't know if second generation bikes have a threaded plug where the thermal switch would go (same housing as first generation). If not, you would have to replace the thermostat housing with one from a first gen....
The second gen does have a threaded boss but that is where the temperature sensor (not over-temp switch!) is installed. :p

However you could certainly employ an over-temp switch from a gen 1 in a hose adapter fitting which are readily available.

The warning light doesn't light up on start up, so to test it you pull the wire at the thermostat from the LED and ground it. The LED should light up.
If you want the LED to illuminate on 'ignition -on' as a 'test' feature simply add a diode to between the overtemp signal and the oil pressure light - then it will come on at ignition (getting ground through the oil pressure switch) & go out when the oil pressure switch is satisfied. The diode will prevent the opposite happening if youget a true overtemp situation (although the overtemp light WILL come on with low oil pressure, but that would be least of your worries!)
The low fuel light already employs this same technique with a diode inside the cluster.


For B.a., the OP - An alternative to adding the thermal switch - a fairly simple comparitor circuit could easily be made to tap off the existing temp sensor in the Gen 2 and use it to trigger a high-temp warning LED. If you can solder electrical components on a board, this can be done for under $10 with only a couple of components. (I can draw it for you if you are capable of putting togther)
 

·
Registered
Joined
·
2,737 Posts
Discussion Starter #5
For B.a., the OP - An alternative to adding the thermal switch - a fairly simple comparitor circuit could easily be made to tap off the existing temp sensor in the Gen 2 and use it to trigger a high-temp warning LED. If you can solder electrical components on a board, this can be done for under $10 with only a couple of components. (I can draw it for you if you are capable of putting togther)
my soldering skills aren't great but if you'd be willing to draw it i'd be willing to try it.
 

·
Registered
Joined
·
3,872 Posts
at what temp do you guys say it is overheating? my bike runs around 186fahrenheit. jumps up to close to 200 or so when i am putting in traffic at very low speeds.
 

·
Registered
Joined
·
6,503 Posts
108C to 115C (227F to 239F) are the check set points for the first generation high temperature warning switch.

That is, it should not close below 108C and it should close at or before 115C.
 

·
Premium Member
Joined
·
3,729 Posts
108C to 115C (227F to 239F) are the check set points for the first generation high temperature warning switch.

That is, it should not close below 108C and it should close at or before 115C.
Not quite - what it means is that the switch closes at 115 as the temp rises, then opens again at 108 as it cools. i.e. there is a hysteresis between close & open temperatures.

On the Gen 2, the high temp LED icon is illuminated at 120 C & actual temp mumerical display flashes between 120 & 129 C; at 130+ C the digital display turns to 'HI' and flashes.
 

·
Registered
Joined
·
28 Posts
HELP! I think I'm another paranoid rider. I've read all the posts but I still wanna ask.

Yes. I'm a newbie. 2008 SV650S. It's got 1200 miles on it and I just had it serviced (for my 650 mile service).

My bike is HOT. I've never experienced the amount of heat on my legs or butt when riding until now. The bike rises quickly to 185F. Within 10 mins I'm stuck in morning traffic. Stopped at a light - it rises quickly - within 10 secs or so - to 215F. by then the light has changed and I get going again. It quickly drops to 185 and once on the freeway, it drops to 175F.

Along with just having it serviced, like an idiot, I blew the starter relay fuse jacking around with the taillight plug. I replaced the starter relay fuse and checked the fan fuse. All good. I was thinking it was one of these events that caused the problem but I don't even know if there is one now that I've read all these posts.

Any help?

Thanks in advance.

Rob.
 

·
Registered
Joined
·
2,737 Posts
Discussion Starter #10
HELP! I think I'm another paranoid rider. I've read all the posts but I still wanna ask.

Yes. I'm a newbie. 2008 SV650S. It's got 1200 miles on it and I just had it serviced (for my 650 mile service).

My bike is HOT. I've never experienced the amount of heat on my legs or butt when riding until now. The bike rises quickly to 185F. Within 10 mins I'm stuck in morning traffic. Stopped at a light - it rises quickly - within 10 secs or so - to 215F. by then the light has changed and I get going again. It quickly drops to 185 and once on the freeway, it drops to 175F.

Along with just having it serviced, like an idiot, I blew the starter relay fuse jacking around with the taillight plug. I replaced the starter relay fuse and checked the fan fuse. All good. I was thinking it was one of these events that caused the problem but I don't even know if there is one now that I've read all these posts.

Any help?

Thanks in advance.

Rob.
i may be wrong but i don't think the fan even kicks on until 226*f i'm pretty sure 215 is with in normal operating temps for a second gen. as long as it cools right down there shouldn't be a problem.
 

·
Registered
Joined
·
28 Posts
215*F for being stopped at a light sounds about right. That's about the average temperatures I run.
Great. Thanks guys. I'm feeling a little better. It's just wild how wide the temp range is.

I've only ridden it in the winter time in houston - 35F - 45F so I've never seen it get this hot. And I've never felt it this hot. I did test the fan wires last night and it's getting juice. Coolant is so full it was dripping off the cap when I removed it.

Guess we're all good.
 

·
Premium Member
Joined
·
3,729 Posts
B.a - here you go

All the part numbers for the components from Radio Shack are on the drawing - total cost incl the indicator LED is $13.20.

Instructions are all there but if you have any questions let me know.

This is called a comparator circuit - there is a reference voltage set on pin 2 which is equal to that generated by the sensor at our desired trip point. The output is 'high' - no LED on - when the temp is below that point and goes low once it is exceeded, turning on the LED.

Important note - I have not tested this but it should work as suggested. If you screw something up I take no responsibility! :p

 
1 - 13 of 13 Posts
Top