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21 will not start


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javes
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21 will not start

Mon Mar 07, 2011 7:27 pm » Post: #1 » Download Post

So, I finally got the stud out and replaced it with a new one. Exhaust in again, fit the fairing and... does not start.

This is a 21 with an R engine and wire splice. When it last stopped, it was running OK except for the leaking exhaust port. What did I do after? removed the airbox and put it on again without mods (just for peeking), removed the plugs so see the colour (dark tan), remove the TPS to check the valves, I think that's all.

Now, it does not start either kicking or pushing. Some details:

- the fuel valve is not tight. I learned this when I removed the tank. It leaks even in the closed position.
- the powervalve does not cycle when the ignition is turned on/off, run switch in either position
- battery voltage is 12.52. Lights, blinkers, etc working.

I have the following suspects: battery, exhauts flanges incorrectly seating, airbox incorrectly connected to carbs, carbs/cylinders flooded, unkonown disconected wire/connector,...

When kicking/pushing there is no sign of an explosion the engine. (by the way, the clutch drags a litle bit when pushing). There seems to be compression...

What should I do next?
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dunkenb

 
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Mon Mar 07, 2011 9:14 pm » Post: #2 » Download Post

Probably the battery on the way out? Nsr's lke anicely charged battery Very Happy
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javes
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Mon Mar 07, 2011 10:26 pm » Post: #3 » Download Post

dunkenb wrote:Probably the battery on the way out? Nsr's lke anicely charged battery Very Happy


I measured 12.5 V. Neutral/sidestand lights come on OK. Main light/blinkers also OK...
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dunkenb

 
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Mon Mar 07, 2011 10:34 pm » Post: #4 » Download Post

Have you checked for a spark at the plugs?
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{.bLanK}GoD

 
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Tue Mar 08, 2011 3:43 am » Post: #5 » Download Post

Kill switch off? lol

javes wrote:remove the TPS to check the valves

Please explain this, The TPS (throttle position sensor) has nothing directly to do with the power valves.

My money's on a bad or disconnected electrical joint.
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nxrsr20

 
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Tue Mar 08, 2011 4:38 am » Post: #6 » Download Post

To check the RC valve cables you disconnect the TS and turn it on, it should cycle to midway. It's in Andy's maintenance/tuning notes.

What's your battery voltage with all your lights and stuff on?

Float heights all ok? You may have flooded your carbs if you don't have a sealing fuel tap.

Checked simple things like spark plug caps back on? Fuel not stale?
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{.bLanK}GoD

 
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Tue Mar 08, 2011 4:58 am » Post: #7 » Download Post

Arh true, I do remember reading (and doing) that now lol. My bad.

Well, that's where I'd start then. If the TPS is not connected properly (open circuit) then I would assume that would probably not let the bike start at all. Even a bad contact will change the resistance of the pot (sensor) to make the sensor reading waaaaaaaaaaaaaaaaaaaaay outta wack.

Unplug the TPS, clean the terminals best you can, check there isn't any damage (wire loose, connectors not connecting) plug it back in and try again.

If it ran before, it is more than likely something you have done to stop it going again. Triple check everything you touched.

N.B. Nsr power vales (under normal circumstances) do not cycle every time the ignition is turned on. IIRC they will cycle the first time the ignition is turned on after the engine has been running and shut down. The Nth time the ignition is turn on (without the engine being started) they do not cycle.

And get that fuel leak fixed.
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javes
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Tue Mar 08, 2011 7:12 am » Post: #8 » Download Post

This afternoon tasks: check for spark, check voltage with lights on, buy charger, check all connections, drain carbs.

{.bLanK}GoD: Is there any way to make the powervalves cycle again?

What I am also missing is the red oil light. It does not light when ignition is turned on. Should it?
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{.bLanK}GoD

 
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Tue Mar 08, 2011 8:05 am » Post: #9 » Download Post

Yes the oil light should come on when the ignition and kill switch is turned on before starting the motor.
e.g.
Ignition = on, kill switch = on, oil light = on
Ignition = on, kill switch = off, oil light = off
If it is not, check the oil tank sensor plug and also the kill switch.

To cycle the power valves again, start the motor. lol.
I think if you disconnect the battery and reconnect it, it might cycle again when you turn the key on.
When setting the valves, i vaguely remember the power valve motor doing it's thing a couple of times.

If you checked the power valves via the nsr-world guide and they are adjusted properly, they'll be sweet. It wont stop the motor from starting. NSRs will start and run with the power valve locked in any position.
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javes
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Tue Mar 08, 2011 5:48 pm » Post: #10 » Download Post

Todays homework:

- no spark (I checked this by removing the plugs from the heads, re-connected them and kicked with the plugs contacting the heads exteral surface. Right?)
- battery voltage 12.2 when lights on. It is now charging, but after 1 hour the "intelligent" charger turned on the green led.
- started to drain the carbs but no drain tubes=mess so I'll fit some tubes. I guess I'll drain all the petrol in the main fuel pipe coming from the tank, right? Also, need to find the correct short tool for the LHS carb.

Reading last post from {.bLanK}GoD I start to suspect the kill switch, since the oil light does not come on in any condition. And the bike stopped working correctly.

Next try will be tomorrow with a fresh charge.
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nxrsr20

 
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Tue Mar 08, 2011 7:35 pm » Post: #11 » Download Post

I had a kill switch fail on me once, very peculiar. I could start the bike with the handle bars straight, but if I turned it to full lock (like you normally would when parked) it wouldn't start.

Check your wiring diagram and it will show you what wires go to the kill switch and which ones you need to bridge out. It's a three pin connector sitting in the wiring box.
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javes
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Tue Mar 08, 2011 9:22 pm » Post: #12 » Download Post

Hey, nice suggestion, nxrs20. I'll check if the steering has any effect on the switch. It is now removed from the handle bar. I'll move it arround an look for false contacts.

I've also looked at the wiring diagram. I can see that the kill switch (2 wires) and the front stop switch (2 wires) join in a "4P mini red". But where is this connector located? It has to be close... Where is the "wiring box"?

Always learning.
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Middo
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Tue Mar 08, 2011 9:24 pm » Post: #13 » Download Post

Just in front of the powervalve servo. There's a whole bunch of connections in there.
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javes
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Wed Mar 09, 2011 7:19 pm » Post: #14 » Download Post

Todays homework:

- battery freshly charged. 12.8 V
- kills switch checked and working correctly. Both sides of the connector.

Still no spark or oil liight. Really don't know how to proceed. I will read the manual, or send the bike to a shop.
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bushman
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Wed Mar 09, 2011 7:45 pm » Post: #15 » Download Post

Not to be pessimistic,but ,when that happened to me,it cost me a PGM Rolling Eyes you could eliminate the oil light by bridging out the level switch in the 2T tank,or maybe the bulb is blown in the dash.Have you checked all the fuses?
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