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1954r25
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Hi guys.

I have a 1954 r25/3 and it will not run. It is getting fuel and spark. I checked the timing and it was off so I put it where I thought its supposed to be. Its sparking when the .S is in the timing window. Is that right? It also has 115 PSI of compression. I was told that was good?

If you have any ideas please let me know.

Thanks.

schrader7032
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VBMWMO #7032
San Antonio, TX
Joined: 10/27/2006
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That all sounds good. 115 is

That all sounds good. 115 is also a reasonable number. Not even a rumble or hint that it wants to start? Is the battery good? The bike needs a good battery to run.

What are you doing to tickle the carb? On my R25/2, I hold the button down maybe a count of 3 or 4. Then I leave the throttle closed, kick the starter about 3 or 4 times, then tun ignition on and kick the starter and it usually fires. I might have to hold the throttle open just a hair sometimes.

If the carb is flooding, then you'll need to open the throttle wide and kick 5-6 times to clear the combustion chamber. Then, with throttle closed, no tickling, kick the starter. That usually works for me.

Out of curiosity, what is the spark plug gap and what was the points gap?

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'78 R100/7 '69 R69S '52 R25/2

Mike Goldthorpe
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A ritual I once used...

...involved turning the fuel on, kicking 4 times with the ignition off then pushing hte key down and kicking.
I read about it in an MZ site and applied it to a barn find Dnepr. It worked - and this was after several of us kicking that darned Ukrainian bike's kickstart for days!
OK, wasn't a first kick after the "MZ Ritual" - first kick just gave a cough, third kick gave a bigger cough which spurred us onto the 3rd kick which resulted in the beast firing up.
As you say, you have a spark that comes at the right time, there's fuel coming out and I assume there's ample air in the mixture. Air, fuel and spark all combine to make an explosion so it should work. Try the ritual and see what happens.

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1954r25
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I am holding the tickle down

I am holding the tickle down until fuel comes out of the top. Then opening the throttle a little bit. Then turning the ignition on and kicking it over. It barely even try's to start. I might get a fart out of it every few kicks but that's it. I also tried push starting it several times and it didn't even try to start.

The spark plug gap is .24 and the points gap it .04 on the tight side.

I am going to try and start it the way you explained. Hope it works.

Thanks

schrader7032
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VBMWMO #7032
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Your flooding it. I don't

Your flooding it. I don't think you need to let gas come out the top. Hold the tickler down for no more than 3-4 seconds. Then try your starting routine.

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

1954r25
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I just tried the starting

I just tried the starting routine and it sounded a lot better. It was close to starting but it still wouldn't. Im pretty sure its flooded again see that now it wont do anything again. So im going to let it sit and try again.

schrader7032
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VBMWMO #7032
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If you suspect it's flooded,

If you suspect it's flooded, you need to clear the combustion chamber. The first steps are to open the throttle wide open and kick the starter 5-6 times. You might also want to turn off the gas. Then turn the ignition on, don't touch the throttle, and see if it will start. Be ready to turn the petcock on.

You might have wetted the plug, possibly ruined it. You may need to remove the plug to check it and let the chamber air out. You could also kick it with the plug removed.

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

1954r25
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I cleared it with the spark

I cleared it with the spark plug out and let it sit for about 20 mins and tried again. Still nothing. I think I might check the valve clearance.

schrader7032
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VBMWMO #7032
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With 115 psi compression, I'd

With 115 psi compression, I'd say that at least the valves are closing for some amount of time....if they never closed, you'd have 0 compression but if they were closed for too long of a time, you'd still have 115 compression but the engine wouldn't breathe properly. Certainly worth verifying they're set right.

In the end, it shouldn't be that hard to get it started. You need a good spark at the right time, good compression, and just the right amount of fuel. Might have to start over and verify each part of that.

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

1954r25
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Do you have any idea what the

Do you have any idea what the resistance of the spark plug wire is supposed to be? Im getting 1.1k ohms.

schrader7032
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VBMWMO #7032
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I would think 0 ohms.

I would think 0 ohms.

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

1954r25
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I know on newer bikes its

I know on newer bikes its usually around 5k ohms. But wasn't sure if the older ones was different. I lost spark all together at the plug now. If I jump the points together with a metal pick and it sparks. Any idea why I have spark at the points but not at the plug?

schrader7032
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VBMWMO #7032
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It's possible that the coil

5K ohms was used in the mid '70s to help with the interference of radios with the ignition system. In the early '70s, the cap was 1K ohms, then it became 5K ohms. The wire has generally always been 0 resistance. Too much resistance in the circuit can create a weak spark.

It's possible that the coil has been damaged. The way the coil works is that when the points are closed, voltage/current is running through the coil, saturating the windings. When the points open, the field collapses and this causes a buildup in current in the secondary windings, resulting a discharge at the spark plug. If the points are closed for a long time (not sure how long that is), the coil can overheat.

Possibilities are:
- coil is damaged
- corrosion in the coil tower where the spark plug wire goes into
- breakdown in the spark plug wire
- the spark plug cap has separated from the wire
- the spark plug is damaged

You'll need to work your way down that list.

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

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