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ahdoman
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Santa Clarita, Ca.
Joined: 08/30/2007
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Hey all,
First I would like to say thanks to everybody for all of the great input but I am about to give up on this one. 1969 R60/US. I got it in pieces, put it back together and rode it very briefly until one of the rings shattered. I just put 1st oversize pistons in, had the barrels bored and honed, rebuilt the heads & carbs (carbs 2 x just to make sure I didn't miss anything because I thought it may be a fuel delivery problem) per manufacturers specs. Got it all together today and it still won't run. I have replaced all of the mechanical bits and the only thing left is electronics and advance system (replaced the points & condensor). I have set up the magneto and points per Vech's "Magneto Blues" paper. Changing the advance (full advance or retard) doesn't seem to make any kind of difference in the way the bike behaves. Here's a couple of the things that are happening;

1) Hard to start (at least 10 to 12 kicks whether hot or cold).
2) Will idle smooth for about 20 seconds then starts running rough and dies almost like it's running out of fuel.
3) Under excelleration it backfires and misses. No apparent pattern. If I hold the throttle in a constant position it runs rougher and rougher and will eventually die.
4) Under deceleration it backfires.

If I could find someone in Los Angeles I would take it to them but the local dealer is really expensive and full of arrogant jerks. I fear that it may be the advance or the magneto both of which I don't have the money to replace on a guess. Any ideas? ...or offers?

oligee7275
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VBMWMO #7275
Joined: 05/31/2007
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Hey Ahdo,
Still sounds like fuel delivery to me. Your description still sounds like it's running out of gas. Idles for 20 seconds smooth then goes down hill.
Start at the gas tank and work your way to the carbs. Make sure you have a constant flow of fuel. Check your floats and level..
Let us know. Don't give up.
Dean

ahdoman
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Santa Clarita, Ca.
Joined: 08/30/2007
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Done that already. I thought that was the culprit as well so this afternoon I took the carbs all apart to make sure nothing was amiss. Everything good per factory spec. I have clear plastic fuel filters and I can see fuel in them. If I hold the "ticklers" down carbs flood so I know delivery is fine. Also sprayed carb cleaner around intakes while the bike was running to check for leaks. Came up negative.

schrader7032
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San Antonio, TX
Joined: 10/27/2006
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Have you put a timing light to verify that the timing is correct? Sounds to me like the gap isn't set right and the timing is all over the map... Do you get a fat, blue spark when you kick it over? Try pulling a plug and laying it on the engine fins so the threads are grounded and kick it...should get nice fat spark.

Valves set properly?

Kurt in S.A.

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

ahdoman
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Santa Clarita, Ca.
Joined: 08/30/2007
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Nice blue spark at points and plugs. Checked gaps on plugs, valves & points. Used the method as described in Vech's paper to set the timing using my ohm meter (static timing?).

Darryl.Richman
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Surf City, USA (Santa Cruz, CA)
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You shouldn't see a spark at the points. This indicates that your condensor is bad. It can make the bike very hard to start, and it will spit and pop when you rev it.

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schrader7032
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San Antonio, TX
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"ahdoman" wrote:

Nice blue spark at points and plugs. Checked gaps on plugs, valves & points. Used the method as described in Vech's paper to set the timing using my ohm meter (static timing?).

I was thinking about possibly using a timing light to actually see the timing marks under operation. Most timing lights are 12v, so you may need to use an alternate source for power, like a nearby car or benchtop battery.

Kurt in S.A.

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

EuroIron
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Joined: 04/23/2007
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although you truly should not see bright blue arcing across the points

the contact points of a perfectly balanced LCR circuit, which is what your ignition system should be....... ideally although very few are actually perfectly balanced, will have some pale orange, but visible arcing, associated with normal operation

however, if it is bright, and or blue, this indicates metal transfering from one contact to the other

and when you have metal transfer from

1)stationary to movable contact

or

2) movable contact to stationary

one way indicates the condenser(C) is at fault and the other indicates the inductance(L) is the culprit

does anyone here know which condition one (1) indicates?

to inspect for metal transfer on the contact points

look, use a magnifying glass if you must, and you will note one contact will have pit forming while the other will have a pimple

just food for thought, before looking there is a 50% chance it could be a condenser or coil to blame for points arcing

common for many ignitions is for the condenser to be at fault but it is not correct to assume this is always the case

ahdoman
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Santa Clarita, Ca.
Joined: 08/30/2007
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Darryl you are the KING! Next time you're in Los Angeles let me know because the I owe you a big steak dinner! I put the old condensor back on and it fired right up! I really should have figured this one out. I assumed that if I had a new part it should work. Apparently I received a bad condensor.
EuroIron - The spark at the points was definitely a bright blue. I looked at the points and there was a little metal transfer between them. I put new points in with the old condensor and it runs! Tongue Laughing

EuroIron
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well if you want to learn something even more useful from it

note which contact lost metal and which one gained it

then if it ever happens the other way around, you'll know to look at your coil

and may save you from chasing your tail

ahdoman
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Santa Clarita, Ca.
Joined: 08/30/2007
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"EuroIron" wrote:

well if you want to learn something even more useful from it

note which contact lost metal and which one gained it

then if it ever happens the other way around, you'll know to look at your coil

and may save you from chasing your tail

So which is which? If the condensor is bad which side of the points will the metal come off of?

oligee7275
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Well I'm glad this came up. I would have chased my tail as well.
This might explain what is wrong with a friend's R-60.
Thanks Darryl.
Dean

Darryl.Richman
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Surf City, USA (Santa Cruz, CA)
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"ahdoman" wrote:

Darryl you are the KING! Next time you're in Los Angeles let me know because the I owe you a big steak dinner! I put the old condensor back on and it fired right up! I really should have figured this one out. I assumed that if I had a new part it should work. Apparently I received a bad condensor.
EuroIron - The spark at the points was definitely a bright blue. I looked at the points and there was a little metal transfer between them. I put new points in with the old condensor and it runs! Tongue Laughing

Drat! I was just in LA two weeks ago. I might be down around Xmas (going to the in-laws out in Riverside)...

Seriously, glad I could help.

I, too, put a new condensor in my R51/3 and it soon demonstrated these problems. I wouldn't have found it if I hadn't run the bike with the front cover off in my garage. The arcing was pronounced. I put the old one back in (never throw parts away), which came with the bike when I bought it, and it turned back into its sweet old self again. (Ok, I did throw away the new condensor.)

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