Hard starting after one month lay up

[RSMike]

I have been traveling for a couple of weeks and consequently the bikes were sitting unused for best part of a month.

Decided to give the R65 a run to work today, but unusually it took a couple of minutes to get her started. It looked like from my paper fuel filter (empty) that the fuel in the lines had somehow leaked or evaporated away over the month. No sign of any leakage in the garage where the bike sat.

At first after turning on the fuel and pressing starter, the bike was turning over but no kick at all, gradually then I could see the filter filling with fuel and after about 2 minutes she fired and ran fine to and from work.

I had some electric issues before I went away and the bike has a new regulator and dual coil, I also had to reset points and timing at that time, and its not really had any road time since,  despite that the empty fuel filter ( and the otherwise perfect running) is making me suspect this was a fuel rather than an electric issue.

I only got the bike in May this year so this is probably the longest period she has not been ridden since I got her, so not sure if this is normal or abnormal behavior?  :-/

[Bob_Roller]

If I run the carbs dry, it takes a good minute to get fuel to stop flowing through the clear filter I have .

Also, some bikes have fuel taps that have a fine mesh screen over the intake tubes inside the tank.

One of those things that gets overlooked, they need to be checked every now and then .

Not knowing what fuel tap you have, there are some with the fuel line coming out at the 6 o'clock position, that don't have the screen over the intake tubes, but instead have a fine mesh plastic filter in the nut on the barbed fitting that the fuel line goes over.

It's a Germa fuel tap, easiest way to determine this is, if the handle you turn to turn the fuel on and off, has a small phillips head screw holding in on, it's a Germa, if it doesn't, it's most likely a Karcoma .

[Barry]

Fuel certainly does evaporate and even if the fuel level is lowered only a little it will weaken the mixture until fuel flows again to top the level up. I have a habit of turning on the fuel tap before rolling the bike off the stand so that the floats get a jolt and some encouragement to operate. Don't know if it does much good I just figure a the fuel level a float delivers with the bike static on the stand might be a touch lower than the level rumbling down the road.

If I don't use the bike for 4 - 8 weeks in the winter lay off I always drop the float bowls and empty them back in the tank. Reason being even if the fuel has not gone off the most volatile fractions of the fuel will have evaporated so what's left will not be conducive to starting. Great thing about an airhead is that it's so easy to do.

Whatever the actually reason engines don't seem to start quite as well when not used regularly.  I owned a bike with only a kick start  for 14 years which focuses the mind somewhat on ease of starting. That one definitely started easier when used on a daily basis.

[oldbiker]

the best cure I find for slow starting after a long lay up is to have the bike on centre stand all the time. Turn on the fuel tap about 10 minutes before you attempt to start.There should be no problem then. I often wondered where the fuel went - our climate so cool. A mate told me it is the same as the fraction of whiskey that disappears while maturing in the barrel -taken by the fairies.

[Barry]

I often wondered where the fuel went - our climate so cool. A mate told me it is the same as the fraction of whiskey that disappears while maturing in the barrel -taken by the fairies.  

Well there you go. I knew there must be a rational explanation.   I have some Irish heritage so I'm definitely a believer.

[RSMike]

Thanks guys, I am reassured by your responses, I should hav eknown the fairies would be around while I was away,  

Bob I have the tap with a 6 o'clock outlet, not sure about other details need to check, however I do have a new tap with 3 o'clock outlet waiting to be fitted, just have not got around to it yet.

[nhmaf]

Another possibility as to why it took a while for the fuel to fill up your filter -besides blocked screen(S) in the fuel petcock- could be that the fuel tank wasn't venting well and you had a partial vacuum in the tank from the evaporated fuel from the lines.   IF this happens again, just try unscrewing the fuel tank cap a bit and listen for a whistle or sucking sound of air, followed by fuel rapidly going down into the filter&carbs.    The fuel cap venting problem is a relatively common occurrence on these old bikes.

[suecanada]

My usual hard starting after a lay over of even 3 weeks lately has been a sticky float on the leftside only. Bike stored on centrestand so I find it odd that it is the leftside float bowl. The float bowl is always found to be too full. So after a couple of manual up and downs of the floats to make sure it does flow fuel and stop fuel from flowing; empty the float bowl and zip up. LRB then is happy! Probably just because he got some much-desired attention! I have the germa petcock as did the former '82 I owned.

[steve hawkins]

Having a full tank also makes a difference with fuel flow......Or at least an almost empty one seems to be tardier with regards to getting through filters and down to the carbs, etc.

But I agree, turn the taps on and give it some time.....

[Barry]

......Or at least an almost empty one seems to be tardier with regards to getting through filters and down to the carbs, etc.  

I find the same. It's also a good reason not to tune the carbs without a decent amount of fuel in the tank.

[Ed Miller]

the best cure I find for slow starting after a long lay up is to have the bike on centre stand all the time. Turn on the fuel tap about 10 minutes before you attempt to start.There should be no problem then. I often wondered where the fuel went - our climate so cool. A mate told me it is the same as the fraction of whiskey that disappears while maturing in the barrel -taken by the fairies.

When I suspect that I won't be riding for more than a few days I also run the carbs down until the bike won't idle any more.  I shut off the fuel tap when I get onto my driveway (a hundred yards long?) and ride up to the shop and let it idle on the center stand for a couple of minutes until it starts to stumble.  

That will keep fuel from gunking up the tiny carb passages as it dries out.