Running rough after winter storage

[Barry]

Well I wouldn't exactly call it winter storage. Last weekend I took the bike out for the first run of the year after only a 35 day layoff.

It started on the button then ran like a pig at low revs - really cold blooded. When properly warmed up I tried blowing out the cobwebs and it sang from 3000 - 6500 rpm but it was still hesitant at low revs.

So I thought pilot circuits and cleaned the pilot jets and transfer ports. Thought I'd found a partial blockage in one pilot jet and was expecting to have fixed the problem.

2nd outing on Thursday it was no better in fact Im sure it was gradually getting worse. Still much more cold blooded than usual and then OK above 3000 rpm. Oddly it ticks over OK so there can't be too much wrong with the pilot circuits but there is a stumble off idle and rough running at low revs. I'm pretty sure it's only one cylinder that's the culprit as the engine shakes side to side just above idle.

Tomorrow I plan to do a complete clean and balance of  the carbs.

Any other thoughts before I dive in ?

[bruce_launceston]

If you haven't allready have a good look at the diaphrams. I am guessing that the symptoms of a hole in one would vary depending on the severity.
I't an easy check to eliminate 1 possibility for a start.

Any sign of water floating in the fuel bowls for a second easy elimination?

Cheers

[Barry]

Thanks Bruce

I just finished one carb and I did find water. Only a tiny spot in the float bowl but quite a bit around the needle jet emulsion tube assembly which suggests it's coming from the engine breather. Diaphragm was fine thankfully.

Next carb after I've digested Sunday lunch.

[Barry]

Right hand carb was clean.

Put all back together and came in to work on it today. I could tell as soon as it fired up that things were back to normal. A few gobs of oily water was all it was. I'm sure the breather favours the left carb as it always seems be this one that gets blocked up. Maybe the breather tubes are not level after the tee piece. I need to look.

[Rob Valdez 79 R65]

There are two schools of thought on lay-up storage.
The more popular is to have the tank as full as you can, with a fuel stabilizer added (we call it Sta-Bil here in the States).

Or you can do what I do, which is to drain all the gas at the end of the season, and remove the petcock so you can inspect for any water or crud, which could include the original factory lining.  I then leave the fill cap off for a few days to allow the tank to dry completely.


The water you found could have come from condensation.  Was it in the left carb?  Do you park the bike on it's sidestand for long periods? (overnight?)

Also, be sure to remove and dump the gas that is in the bowls at the end of the season.

[Barry]

I don't take any special precautions as the bike lives in partially heated garage that rarely drops below 10 Deg C and I had drained and flushed the tank not many weeks before.  Didn't fill it to the top though. On the other hand we have had some big temperature fluctuations with -16 Deg C outside overnight. I did drain the float bowls halfway through the storage and again before first use with no sign of water, well maybe a tiny spot.

Never use the side stand for more than a few minutes at least not since I learnt not to do it from the smoke cloud.

Maybe I've got some condensation in the oil. It never gets hot enough at this time of year.  I'll take the long route home and see if I can get it really warmed up.

[Rob Valdez 79 R65]

Not only that, but condensation can wreck havoc with your mufflers on short trips that don't get everything up to temp.

[steve hawkins]

I had a similar issue with my R100 last year, only it took me a little longer to find it.  Water in the float bowels.  

Once I found why the rough running was occuring I allowed the tank to go low and then drained the tank completely.  Water had probably got in via the cap - I wash the bike regularly, or it could have been when the bike was left out in the rain or just condensation.  Mine happened during the spring/early summer.  So its not just a winter thing.

First place I check these days.

Steve H