R60/5 - To Buy?

[hudson]

Hey guys - I was looking at buying an R60/5 for my wife, but it has an issue (s) I am not sure about. It starts up unwillingly after a few tries with the chokes on, and then to keep it running- turn off chokes after 5-10 seconds, and then hold throttle open just a bit until it is ok on its own - maybe 20 more additional seconds. Once it gets running -it idles, accelerates (applying throttle on the centerstand) and engine sounds fine as it runs. The valve clearances were checked recently and good, so the hard starting doesn't seem to be due to tight valves settings.

SInce it was hard starting, I pulled the plugs and one side is totally clean, as if not igniting. I tested spark on the cylinder head and it was sparking. It has electronic ignition.

Then I noticed that the fuel was dripping out of the header pipe at the exhaust clamp while it was idling. It isn't a drip or two and then stops, but a sort of a slow stream. I feel the cylinder head cover and can feel it working ( I guess that side would stall out and gas wouldn't come out of the header -just seep down through the rings).

So, Assuming timing and carb synch is ok (again runs good after this brief starting debacle):

Is this more of a carb running way too rich (perhaps stuck needle or floats) - would that wash the plug clean and cause fuel to seep out of the header clamp - or is that too minimal of a symptom to cause this amount of leak?

Or perhaps an exhaust valve issue?

Low idle setting? Or something else?

I don't mind doing some repairs, but obviously I can't pull the heads.

Any ideas of the causes?

Thanks!

[barryh]

Are you sure it was fuel dripping out of the exhaust rather than condensate from the cold exhaust.

Few people sell a bike of that age that's been in recent regular use, they sell because they are not using it. When that's the case then starting and cold running problems are possible and may clear up once the bike is back in use. Bikes that start instantly are the ones used daily or at least regularly. Given it runs well once started I would buy a bike like that on overall condition.

[Rob Frankham]

It doesn't sound like there's a lot wrong with it, The starting and warm up is pretty normal for this age of airhead... in fact for pretty much all bikes of this vintage. In those days automatic chokes and temperature compensation circuits were a thing of the future on bikes. It may well be that a good service will improve the starting but there is definitely a knack and, once the bike is serviced and in regular use, I'd be prepared to bet that this problem will just go away.

Fuel from the header clamp is more concerning but still probably nothing serious... As Barry says, are you sure it's fuel and that it is in fact coming from the exhaust. Bikes of this age (in fact all airheads) are prone to leakage from the carbs and this would take the fuel down onto the clamp between the header and the silencer (I'm assuming that's where you're seeing the leakage rather than at the header/head joint). Leakage from the carb is normally easy enough to solve with a full service, new float needles and gasket. If the leakage is indeed from the header and if it does turn out to be fuel rather than condensed water, then a deeper investigation is called for but it's difficult to see how you would get liquid fuel from here in an engine that is firing on all cylinders. The only possibility I can think of is that the starting issue allowed some liquid fuel through into the exhaust but I would expect that to dry up very quickly (and possibly noisily) as soon as the cylinder started firing.

In your place, I would want to see the engine run up to temperature to see whether the leak dries up and whether the running settles down. By up to temperature, I mean at least 10 to 15 minutes and preferably under riding conditions (bear in mind these engines can overheat if left idling for too long).

Incidentally, on the airhead, a head job is well within the abilities of a moderately competent amateur wrench. Airheads are very easy to work on.

Three further comments...

1) The R60 is not the fastest of bikes, are you happy that the performance is adequate?

2) The front twin leading shoe brake is quite quirky. Don't get me wrong, it's a good brake... probably better than the contemporary disc setup but the feel is quite differnt to any disc. In particular, it needs a lot more effort to work backwards... quite important on hill starts.

3) The clutch on the early airheads is notoriously heavy. If you're used to a modern multi-plate clutch, working in traffic can be quite testing. Make sure your good lady has tried the clutch before you buy...

The /5 series are lovely bikes but always bear in mind that the last of them was built in 1974, over 50 years ago. Technology has come a long way since then.

Kind regards and Happy New Year

Rob

[hudson]

Hey guys, I appreciate the input. Cheap bike for local riding is all that it is for.

yes it's definitely fuel and it is seeping from the header finned nut/ clamp where it threads into the exhaust port of the cylinder head. (Not the clamp below connecting header with the silencer below. Fuel runs out of the finned nut down the exterior of the header pipe curve and drips on the ground). Never seen anything like this before so I am puzzled if really that much extra fuel can be produced from the carb into the intake. Or if after it starts the RH side eventually maybe stops detonating because of the fuel overflow from the carb (I didn't leave my hand on it the whole time as I was checking on other things). But if that were the case, wouldn't the engine stumble a bit when the RH side quit? It didn't seem to to that. After I ran it, I pulled the RH spark plug and it is totally clean despite the prolonged idling. Normally this would be dark because of the rich condition of idling. The fuel doesn't seem to fully stop and we only want run it for so long, so test driving is not in the cards.

As an amateur wrench, I am not necessarily afraid to get my hands dirty, I am trying to hopefully find the cause first then deduce costs to repair. Naturally, I can't pull the heads unless I bring it home.

So confirming this fuel leak location, probably carb only?... valve issues?... or?

Also, If we took the carb issues out of the equation for a moment, and if this leak continued - what other things would you check?

Thanks!

[Rob Frankham]

Thanks for the additional information...

This is a difficult one to diagnose remotely. It has to be a carb issue... the only place fuel can come from is the carb really... but, as you say, it is dificult to see reconcile the fact of fuel emerging at the exhaust/head joint with the observed fact that the relevant cylinder is firing. How certain are you that the cylinder was, in fact, firing? Did the header get hot? It would certainly make more sense if the cylinder wasn't firing. If this were the case, I would be suspecting the float/float needle combination or a flaw in the carb body to let liquid fuel into the inlet tract.

I don't in fact think that a lot more can be done without dismantling. If you aren't willing to pay out for something that is a bit of an unknown quantity, it might be better to give this one a miss. It very much depends on much the vendor is asking and how willing you are to undertake a trouble shooting exercise with the possibility of some undetermined additional expenditure to get the bike right.

Rob

[hudson]

Thanks for the input, I do appreciate it. I will pass on it. Too much unknown as you stated.