1963 BMW R69S bogging down on acceleration

[41indian]

Last ride on the bike was beautiful. Sat for about a week now it boggs down on acceleration. Took carb apart no issues, plenty of gas flowing. Haven't looked at ignition yet but seems like a gas problem?

See video any advice is welcome

http://youtu.be/90MpIZbZPS8

[jmatch]

Always check for water in float bowls if something like this happens to a normally good running bike. Also if the bike still has points they may have worn down and are not opening fully. That's two quick and easy checks, good luck! JF in NC '66 R60

[Shaky Jake]

What do the plugs look like? That might give you a clue as to what is going on.

I agree with checking the easy things first; mouse nest in the air cleaner, valve clearances, ...



Kevin


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[panthersteve]

It sounds more of a spark issue to me. Maybe one plug or lead is not quite right.

[41indian]

reply to ideas

Thanks guys
1. Carbs look good tore them down and no changes
2. Air cleaner is good and run the same even if I remove it
3. I haven't cracked the front cover to see if I have a points problem yet.

One more thing of note is that is I rev up slowly it will keep up but when I open the throttle all the way it bog and will eventually die.

[Shaky Jake]

It sounds like it's affecting both sides, so an ignition problem makes sense. The coils and condensers on /2's are notorious. Does it have the original coil, or a repop? If I recall correctly, you can use a condenser for a ford V8 from the days of points ignitions. Auto parts stores usually have them. Bench Mark Works has coils. Good luck...



Kevin

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[panthersteve]

Hi
How are you going with this?
I'm interested to hear what the problem is/was.
Cheers
Steve

[41indian]

Hi
How are you going with this?
I'm interested to hear what the problem is/was.
Cheers
Steve

Hey no progress crazy week!! Hope to look at electrical this weekend, just so weird that is was a binary impact ran great last ride and then crap the next. Looking back the only thing I did was take the air cleaner off and charge the battery and put it back on.

[41indian]

Ok points look good gap at 0.016", cams move freely and work on acceleration when I do slow slowly. Out of easy ideas to to go see Scottie Sharpe

[Pokie]

Sounds to me like a carb issue. Is the bike fully warmed up? When a /2 is cold, it will continue to bog until you tickle the carbs more. If the temperature outside is cold, more time will be required to warm the engine. If this is the problem, having the intake tubes off will exacerbate the problem because it can pull pre-warmed air from the top of the transmission/ engine. Try tickling the carbs while the bike is running to see if the problem stops. Tickle the carbs for a couple of seconds while the bike is idling then try accelerating. This may also occur if the timing is very retarded.

[41indian]

No luck loaded them up and same issue. The only thing that kind of works is a slow acceleration but even then I can never get full open before it bogs down and dies.

[frichie68]

This problem tickles my feeble memory. Have you tried pulling spark plug wires off one at a time to see if it will idle on one cylinder?
Adjust idle speed up a bit if needed. If that narrows the problem down to one side its a starting point.

I had this sort of problem once, caused by a hole in a carb diaphragm. Don't even recall what brand bike, I've had several over the years.

[panthersteve]

Hi

You've had a bit of time to sort the problem out, how is it going ?

Cheers
Steve

[Coolbreeze]

Of course it is carburetion. The symptoms described are exactly what happens with a cold engine that needs more choke or when you have an air leak. For whatever reason (obstructed fuel or air leak), your mixture is too lean.
Please let us know what you find.