Stall at idle

[Puffs]

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[Blurredman]

Okay guys,

I've come to a few conclusions as of this morning.

Firstly. Last night I couldn't reproduce the problem after getting home. But I swapped the relay with my 251 anyway (they are both original relays- one is NOS actually).

I left the multimeter out in order to do a quick test this morning and found the battery standing was at 12.18v - which obviously is getting low and towards unusable.

After getting to work I could only somewhat reproduce the problem. After minutes and minutes of idling with load, idle was kinda fluffy at around 1100 and I could tell it wanted to stall- but didn't.

I realise however that going to work is going into traffic and more stop/start situations. Going home from work I have about 5 miles of dual carriageway @ 60 so I suppose that tops up the battery.


So yes, I didn't rule out the battery in this most recent occasion of problems, but that last voltage check was about 5 weeks ago before the cold became so prevelant, and it is an aging battery (I think over 4 years old now). The other years of issues may have been some other things that I've maybe fixed but incorrectly attributed to be the same problems.

I also realise that maybe the 251 (with same battery) might not have been a problem because i've only required lights to be used (I mean.. all the time..) as opposed to just occasionally in twilight just before the fading day or bad weather conditions.



I'll charge the battery on the weekend for a good long time and double check standing voltage after a day or two of work use.

[DAVID THOMPSON]

my 2002 rt125 4t idles at 1800 to 1900 rpm on a accurate tachometer
any lower and the oil pressure lamp flickers with 20w 50 oil
it must be getting real loose at 23,000 miles

[Puffs]

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[DAVID THOMPSON]

i ran this oil from first change
i did buffalo NY to Parkersburg WV 360 miles in 10 hours and the light was flickering
even at 2000 rpm/udm
Stepson said change the oil and filter old man you did a job on it

i changed oil and lamp flicker went away at 1800 rpm..

[JawasandMZs]

You've done TWO failed electronic ignition upgrades? Eh?
That's not very encouraging. I'm thinking of paying £240 for a full Vape upgrade.

[Puffs]

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[DAVID THOMPSON]

the rt125 has been ran hard
but i try not to destroy it
it is so fun to ride

like a little airplane they forgot to put the wings on

[Blurredman]

You've done TWO failed electronic ignition upgrades? Eh?
That's not very encouraging. I'm thinking of paying £240 for a full Vape upgrade.

No. Neither failed. Infact they worked very well. Both different electronic designs aswell. I didn't really want to use electronic ignition on the bike, I like it kept all original. One kit was put back onto my 251 where it's always been grand on- the other I sold. I like having the points on this bike.



As far as my problem goes- I topped up the battery and gave it several hours on the slow charger today so will have to see what it's like next week. Will have to check standing voltage before I ride off, each morning to check the condition of the battery.


After all- it does say in the official service manual that the battery should be put on a charger every 1 month..

[Puffs]

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[Blurredman]

So as I mentioned I had topped up and slow charged the bat on Sat.

On Sunday I checked the battery standing and it was 12.58v.

This morning at around 2c (35/36f), it was 12.41v.

Maybe the cold isn't doing it the best.


Anyway. I'll put this topic to rest unless I find/get any info. I suppose for now, the best thing to do at long stops is just to put the bike in neutral for now (and then the idle will increase 200rpm ish).

[nice2day]

Hi Puffs just noticed your message:

thinking a bit more about the idea of connecting a LED on the ignition coil primary, that'll work fine for detecting the ignition timing. But when the engine runs, the opening of the points will create a more significant V, at the exit pole of the primary winding. And that will burn the LED. Maybe not if a more significant R is used, or a high voltage diode added, but then it might not work at low revs. Maybe not such a good idea.

First I'm lost as to who suggested using the LED as a timing device. Maybe I missed it but I suggested using an LED or conventional bulb to readily display if the coil was receiving its normal 12V supply.

As regards:

the opening of the points will create a more significant V, at the exit pole of the primary winding

I don't understand this either. Yes, when the coils supply is interrupted by the points there is a significant self induced voltage produced (Back EMF) but this is produced at the contact breaker side and is mostly absorbed by the capacitor (condenser) wired across the points. There will no voltage peaks at terminal 15, the main power input to the coil, as this is swamped by the very low impedance battery which it is connected to for its power. The voltage driving the LED or filament bulb will remain just as constant (12.5V -14.5v) as any other electrical device being driven by the bikes battery. Could you explain what you mean Puffs please?

Les

[Puffs]

Les, on the electrics bit I'll reply to you in a PM.

Blurredman, IMO it's always better to put it in neutral before you come to a standstill. Reduces wear on plates & thrust bearing. Anyway, hope that solves the stalling problem.

[Blurredman]

I think I have solved this issue..

Interestingly whilst I was perusing an issue in another bike....

I borrowed the spark plug from the bike in question in this topic, and found that my 251 was instead stalling at idle when waiting at junctions with electrical load primarily on, to the point that it was stalling at the exact same locations! Putting the original spark plug back in the 251 that it did have I found that it no longer stalled..

I have yet to actually test my etz250 on this (with a new spark plug), but because of the above I am confident that I have found the cause, and the solution.