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Discussion Starter #1
Yes Eclipze the dollar signs were to get your attention there is no real money on this thread! :)

I am about to pull my hair out with this perticular problem.
I have the Rs 125 nearly ready to go apart from 2 things.
A breather pipe that some man in aprilia must be hand making it's taking so fucking long.

And a temperture reading that has a mind of it's own!

When I turn the ignition on it says 09 then randomly the temp jumps about.
It can read 00, 01, 79, 108 and it does all this without starting the bike.

So far I have lubed all the connections, used a second hand temp sensor, a different set of clocks and today a brand new temp sensor from aprilia.
None of these changed a thing, the temp still has a mind of it's own.
On a 2stroke it's very important to have an accurate temp.

So I NEED this to work.
My guess is that the the wire is spit somewhere or is earthing off something.

Here is a wiring diagram


how can I test the line?
I'm a multimeter retard on a good day so spell it out.

The black white wire goes from the temp sensor (earthed to the engine) to the clocks through one connector.
Does the cdi even come into play? As in could it be sending false readings.
I don't think it's even in the equation.

Should I strip the lume looking for the fault?
Cheers.
 

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the different clocks give you the same problems?

get a length of wire and by pass the black/white wire if it works you know the wire is at fault. it could be corroded and creating resistance
 

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Discussion Starter #3
Good thinking batman!
Now to find a wire that isn't the one I pull everyday!
Cheers will let ya know.
 

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Pfft... since when has $$$ signs been needed to attract my attention! A good brand of beer, a bbq or a NWS title maybe :)

Zanes idea is a good one.

To use a multimeter, ignition off, put the meter on the resistance setting and measure between the two distance points on the wire. You should get a very low reading if it's good, less than an ohm.

Next, test the resistance between the temperature sensor body and the -ve terminal of the battery. That should also be less than an ohm. If not... have a look at the ground lead from the battery to the chassis, and make sure it's a good connection and not loose. Make sure those connections are clean too.

Next, have a look at the instrument connector, specifically the black/white wire. Make sure the one of the terminals hasn't "backed itself" out of the connector housing.
 

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has it come to that time when i need to come to the rescue?
 

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Discussion Starter #7
zane said:
has it come to that time when i need to come to the rescue?

Maybe batman, Myles is having a look at it later but if not im calling in a pro.... thats you batman!:hail:
 

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I take it this is the old shape RS?

If your readings with the multimeter tests (above) are fine, then jiggle the connector, different parts of the loom and see if the resistance changes. If it does, then it means you've got a developing fault in that wire.
 

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Discussion Starter #9
All the tests went fine, but I think I have water damage in the clocks!!!
Even though ihave tried a set of clocks from a mate and it made fuck all difference?
I will try a third set of clocks to be sure.
Cheers lads.
 

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Have you tried http://www.apriliaforum.com/ they helped me with all my issues (and current issues FFS) with my RS250 good bunch of blokes and a whole heap of knowhow. Plus the shop is good for parts.
 

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Discussion Starter #11
Turned out to be water damage at the back of the LCD screen on the chip.
Brand new one from eBay and alas we have a temperture reading.

Unfortunatley it is reading very hot when driving so I will rebleed the system and see how she goes.
If it doesn't run any cooler it may be the water pump but they run off the crank internaly so it's an engine out job.
 

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Discussion Starter #13
mekros said:
check that your thermostat is working before you pull the engine out.
the bike never had a thermostat with it. Previous owner took it out.
I just wait longer for it to warm up.


Ok so I have rebleed the system a couple oftimes but she is running way too hot still.
She takes ages to get up to 60 dueto no thermostat, then I get on it and it rapidly goes to about 90 and keeps rising to the 100s and above.
I have a small seep in my radiator, that may be introducing air so I may get a new rad.
After that I suspect the water pump, something I am not looking farward to doing.
 

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Definitely get your radiator fixed/replaced.

Have you also confirmed that when the previous owner removed the thermostat, he didn't replace it with a flow restrictor?
 

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Discussion Starter #15
Well I found the overheating problem, turns out who ever rebuilt/or removed the water pump before never put the pin back in on the impeller.


So i have gottne a new pin now and ill test it tommorow.
 
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