Airone info

[Joseph Joe]

A new owner of a 1947 (?) Airone asked me for information on:

 

1.  Valve clearances for his exposed valve Airone. Does anyone have the correct clearances for setting valve timing and then the actual running clearances for this setup? For my exposed valve SA, the initial clearance to set to 0.20mm for both valves. Once the valve timing is set, the clearance is adjusted to 0.05mm for intake and 0.30mm for exhaust. However, a manual he has calls for 0.02mm for the intake and 0.20mm for the exhaust but he is not sure if this for the covered or exposed valves.

 

2. Float needle height. He is not sure if his float on his 22mm Dellorto is set to the right height. Anyone have any info on float heights on this carb?

 

I am copying Adam on this email: welcome to the group, Adam!

 

Joe

 

 

[antonio]

It would help to know what carburetor we are talking about. Generically
on those old carbs there was only one position and no adjustment. On the
remote bowls of the SSIs one just adjusted the height of the bowl
itself; this set up however was intended only for racing.
Zipolo

[Joseph Joe]

Good point. I copied Adam on the original email and I am sure he will respond. I assume it is a Dellorto MD22?

 

Yes, there is only one setting for the float needle, but Adam says there apparently is an adjuster screw on top of the float bowl that can be used to adjust the height of the float. I have not seen the machine and am not familiar with the Airone.

--
You received this message because you are subscribed to the Google Groups "Guzzi Singles" group.
To unsubscribe from this group and stop receiving emails from it, send an email to guzzi-singles+unsub...@googlegroups.com.
To post to this group, send email to guzzi-...@googlegroups.com.
Visit this group at http://groups.google.com/group/guzzi-singles.
For more options, visit https://groups.google.com/groups/opt_out.

[antonio]

On top of the bowl of the MD 22 there is a screw that deforms the
threads so that the top does not come loose and a tickler to flood the
carb for cold starts. I do not recall any adjustment screw, but I will
check my books.

[Mike Peavey]

Not sure which carb was standard on the 47' , but the SBF22, from the early 50's Airone Turismo is, as Antonio suggest,  the float height is dictated by a single notch on the needle.  The SBF has no screw in the cap, but does have a hex nut cast into the bowl cap/top, but that's only for removal.  My SSF25A on the Sport does have a small have a small nut in the bowl cap, but thats for locking the cap on.

On this model, my experience with flooding, if that's Adam's issue, has been caused by a worn needle and/or the seat. 

Mike

To unsubscribe from this group and stop receiving emails from it, send an email to guzzi-single...@googlegroups.com.

[Mac Dennis]

Speaking of SSF 25A is there any place to get stock jets and needle?

Years ago when a got my '50 Airone Sport it would idle or run wide open but not much in between. I ended up replacing the needle from a V7 SSI and it has worked fairly well but it would be nice to get new ones installed.

Mac

[Don West]

Mac

 

Eurocarb in England do stock a good range of Dellorto parts and supply very quickly to UK customers. US may take a little longer to get to.

Have a check out of their website:-

http://www.dellorto.co.uk/merchandise/Carburetor_parts.asp?CategoryID=25&PartsectionID=132

There are various parts lists etc available to download for free showing assemblies etc.  They supplied me with several parts for my Stornello and they arrived next day.

Don

[Jerome Kimberlin]

On 8/20/2013 5:45 AM, Joseph Joe wrote:

A new owner of a 1947 (?) Airone asked me for information on:

 

1.  Valve clearances for his exposed valve Airone. Does anyone have the correct clearances for setting valve timing and then the actual running clearances for this setup? For my exposed valve SA, the initial clearance to set to 0.20mm for both valves. Once the valve timing is set, the clearance is adjusted to 0.05mm for intake and 0.30mm for exhaust. However, a manual he has calls for 0.02mm for the intake and 0.20mm for the exhaust but he is not sure if this for the covered or exposed valves.

Joe, I would guess the 0.02 and 0.20 mm would be correct for the open valve Airone.  The enclosed valve type would require more of an even dimensional clearance due to the oil cooling.  Actually it is pretty easy to tell once the engine is hot.  There should be some clearance when hot but not much.  The dimensions he has are probably for a cold engine and these will close up a little when hot, exhaust more than intake due to the heat differential.

JerryK

[Adam RocketMoto]

Hi Zipolo:

I found a manual for a '47 Airone on www.rpw.it. I have Google translated the appropriate sections, so I have the basic idea of what's what - I think. If there is a proper owner's, service and parts manual for this bike, I'd be interested in purchasing or obtaining copies.

My Airone was first sold in 1945 (according to a factory letter), but I would guess it's a '40 or '41, as I don't think there were civilian bikes at the time. The bike was first sold 8th-May-1945 in Mandello. The engine has the external hairspring valve train and front suspension is girder-type forks. 

I am trying to sort out a number of things, since the bike is unbelievably hard to start. Once it does start, it will die in about 5-10 seconds at tick-over. If I rev the engine a bit, it will run, and a timing light shows a mark I made on the flywheel close to what I believe is full advance.

The carburetor is an SBF22. I've cleaned it thoroughly - more than once. The slide is not loose in the carb body and as far as I can tell, everything is in fine shape.

 With regards to the carburetor, I'd like to know:

• What the float height should be, and what the length of the float needle should be.
• The reason I ask is that when I depress the the tickler, it does not depress the top of the float to flood the carburetor. There is a 'jam nut' on the fuel inlet fitting that would permit a change to the height of the fuel inlet, and in turn, the height of the float. I'm not sure whether the jam nut is supposed to be on the inlet fitting or not.
  
• Would a photo of this be useful of this?
  
  
• What is the proper jetting is for this carburetor? I believe it is correct, but just want to verify.
  
  

Valve lash adjustment:

• What is the proper clearance for intake and exhaust valves? The manual indicates 0.05mm for intake (which seems too tight?) and 0.3mm for exhaust (which seems too loose?). But what do I know?
  
  

Ignition timing at full advance, points, spark:

• Let me be sure I have this correct...
• Advance lever pulled - full advance.
• Mark the flywheel 80mm 'clockwise' from the TDC mark.
• At this mark, the magneto points should begin to open (and they do) - correct?
  
  
• What is the correct magneto points gap?
• I have checked for good spark - and I believe it is. I took a spare plug, and bent the ground electrode to about 7mm, and I get a consistent spark jumping this big gap
• 18mm spark plug. I have installed an NGK AB-6. Good? Alternative suggestions?

Battery:

• I have a fresh 6 volt sealed lead acid battery fitted. Is the battery required for starting, or only to power the lighting?

That's about it for the moment. Thank you for any info that you can provide.

=Adam=

rocketmoto.com

Hollis, NH USA

[Mike Peavey]

Adam, 

Here's what's in my SBF22

Main 105

Idle 50

Slide 70

Needle H2

Float 11 grams

Float needle, no markings, but 65.54 long.   The tickling button does act on needle to displace the float when depressed. 

I 'm assuming you do have the enriching slide working?

Mike

--

[Adam RocketMoto]

Hi Mike:

Thanks. I will check my carb to see what's in there. On your fuel inlet fitting, does it screw directly into the float bowl, or is there a jam nut in-between the fitting and the float bowl bottom?

When at a proper fuel level, what is the distance from the top of the float to the rim of the float bowl? This is governed by the length of the float needle and seat (fuel inlet fitting). Just looking for a comparison of yours to mine.

Regards,
=Adam=

[Mike Peavey]

Adam, 

Measured right at the needle, 16.39mm below the level of the bowl rim.

But now that you mention the jam nut, I'd be willing to bet that's your problem, the jam nut goes inside the bowl. Thread the seat from the outside into the bottom of the bowl and then drop the jam nut into the bowl and tighten.

Mike

[Adam RocketMoto]

DOH!  

It was outside the bowl, originally, so that's where I put it back. I haven't been able to find the diagram for SBF22. Ya' got one?

Well, we can check off one problem...

Regards,
=Adam=

[Guzz...@aol.com]

I found a manual here for my later model airone ....... www.moto-manual.com

My bike is around a 1948 or 49' model I think ??

Welcome aboard Adam ..........

 

,,,,,,,,Tim

[Jerome Kimberlin]

On 8/20/2013 9:14 AM, Adam RocketMoto wrote:

I found a manual for a '47 Airone on www.rpw.it. I have Google
translated the appropriate sections, so I have the basic idea of what's
what - I think. If there is a proper owner's, service and parts manual
for this bike, I'd be interested in purchasing or obtaining copies.

Adam, I'm sending you an article on the 1939-1940 Airone that appeared
in Legend Bike #82. It is a good article but it's in Italian. You can
read the technical info easily enough, however.

JerryK

[Mac Dennis]

Thanks Don!

Mac

[antonio]

Adam, I am not an Airone expert but making these old guzzi engines work
is not rocket (ha,ha) science.
I know those carbs though. from your description I cannot for sure tell
where the jam nut is but, here is the story.
The jam nut secures the needle's cone housing to the bowl; the housing
itself is screwed into the bottom of the
bowl and the jam nut locks it in place. If the jam nut is installed
outside the carb, it moves the needle away from
the tickler and lowers the float assembly. check on this, it will make
a difference. also check the idle jet there are 3
very small holes in it that have to be clean: one, vertical, inside the
cone of the wiggly piece and 2, on the diameter of the little tube.
also on e-bay (if you google SBF22) you will find some of the parts in
question.
good luck

[Adam RocketMoto]

Antonio:

Thanks for your email!

I was thinking that since the float needle has only one notch, the jam nut was used to adjust the float height by raising or lowering the inlet fitting. Guess not - duh!

The pilot jet is absolutely spic and span - operating room clean.

Will mess with the carb - I guess the bike needs gasoline to run. Will also re-check the valve clearances and check valve timing with a dial indicator.

Regards,
=Adam=

Adam Schoolsky  | ad...@RocketMoto.com
RocketMoto.com | For Love of the Ride (™)
Tel/Fax 1 877.533.4245 or +1 978.517.1212

--
You received this message because you are subscribed to the Google Groups "Guzzi Singles" group.

To unsubscribe from this group and stop receiving emails from it, send an email to guzzi-singles+unsubscribe@googlegroups.com.

[Rossi, Steven (CT13)]

And check the valve lift.

 

Sounds just like that machine I mentioned to you on Sunday, that we were messin’ with. It idled fine, ran well at low speed…but would fall on its face above 25 mph, or so. Turned out that the exhaust cam lobe was worn down to almost nothing. Had great compression, though!

 

Steven Rossi

 

From: guzzi-...@googlegroups.com [mailto:guzzi-...@googlegroups.com] On Behalf Of Adam RocketMoto
Sent: Wednesday, August 21, 2013 12:09 PM
To: guzzi-...@googlegroups.com
Subject: Re: [guzzi-singles] Airone info

 

Antonio:

 

Thanks for your email!

 

I was thinking that since the float needle has only one notch, the jam nut was used to adjust the float height by raising or lowering the inlet fitting. Guess not - duh!

 

The pilot jet is absolutely spic and span - operating room clean.

 

Will mess with the carb - I guess the bike needs gasoline to run. Will also re-check the valve clearances and check valve timing with a dial indicator.

 

Regards,
=Adam=

Adam Schoolsky  | ad...@RocketMoto.com
RocketMoto.com | For Love of the Ride (™)
Tel/Fax 1 877.533.4245 or +1 978.517.1212

 

On Wed, Aug 21, 2013 at 9:05 AM, antonio <pagt...@wcnet.org> wrote:

Adam, I am not an Airone expert but making these old guzzi engines work is not rocket (ha,ha) science.
I know those carbs though. from your description I cannot for sure tell where the jam nut is but, here is the story.
The jam nut secures the needle's cone housing to the bowl; the housing itself is screwed into the bottom of the
bowl and the jam nut locks it in place. If the jam nut is installed outside the carb, it moves the needle away from
the tickler and lowers the float assembly.  check on this, it will make a difference. also check the idle jet there are 3
very small holes in it that have to be clean: one, vertical, inside the cone of the wiggly piece and 2, on the diameter of the little tube.
also on e-bay (if you google SBF22) you will find some of the parts in question.
good luck

--
You received this message because you are subscribed to the Google Groups "Guzzi Singles" group.

To unsubscribe from this group and stop receiving emails from it, send an email to guzzi-single...@googlegroups.com.

To post to this group, send email to guzzi-...@googlegroups.com.
Visit this group at http://groups.google.com/group/guzzi-singles.
For more options, visit https://groups.google.com/groups/opt_out.

 

--

You received this message because you are subscribed to the Google Groups "Guzzi Singles" group.

To unsubscribe from this group and stop receiving emails from it, send an email to guzzi-single...@googlegroups.com.

[antonio]

Adam, my italian is impeccable so, if you need some translation let me
know, before you trust google services.
Some of theese limit themselves to translate words; languages are living
things so sometimes what appears to
be the same thing has different meaning depending on the context.
Good luck
Zipolo

[Patrick Hayes]

Oh, brother, did I learn that one. I know enough Italian to get into
trouble.

I was leading a long distance tour group of Italians. Someone asked how
far it was to some location. Straight line was one distance, along the
curving roads was another distance. I tried to explain that
differential in Italian.

In America, we would use the expression "As the crow flies" to represent
straight line travel. I said something akin to "100 km, always
straight, the way a bird flies". I think it was maybe " centro km,
sempre dritto, come un uccello".

Glorious uproar. Apparently the last few words have an alternate,
idiomatic meaning in reference to certain male anatomy. 100km!!!

Patrick Hayes
Fremont CA

[Bill Irwin]

Hi Adam

In my experience the problem with a hard to start old single is almost always the spark. Mixture has to be precise for smooth running but for starting it just needs to be in the explosive range. 

A good mag will throw a half inch spark and start a bike first kick all else being ok. A poor one will provide lots of kicking practice. 

Cheers Bill

To unsubscribe from this group and stop receiving emails from it, send an email to guzzi-single...@googlegroups.com.

[Adam RocketMoto]

Definitely, Steve. Bought a magnetic holder for my dial indicator - hope to get to this over the weekend. Time is running short if I am going to get ready for the Giro, come mid-September.

BTW, I did get a first place award in the Euro class at the Brit jam meet for the Airone. Now to make her run.

=Adam=

[Adam RocketMoto]

Bill - and everyone else...

Well, progress, I think. Re-fitted the fuel inlet, checked the jets, float and slide needles. Doesn't seem that getting enough fuel now is an issue, now that the 'jam nut' is inside the float bowl. Tickle carb. Fuel squirts out of hole in top cover. Wet sparkplug, OK.

I don't think this is the issue with starting and running at tick-over  -- but any idea what the valve lift should be?

Now, on to the Magneto. There's a worn 'crater' in the center of the low spot (points open area - see pic) of the advance ring/cam. What's the proper name for this ring? This spot will cause the rubbing block on the point to wear faster and the point gap to be too wide over this spot. Swell. Although I don't think this is the starting (and tick-over) issue by itself.

Would anyone have a spare piece available, or no where this one could be repaired? Also, where I can I find a points rubbing block?

On to check the valve timing...

=Adam=

[Mike Peavey]

Adam, not sure how different the exposed rocker "lift" is compared to the covered rockers, but I just measured my lift  a couple of weeks ago for Dave Roper and this what I came up with..   

The gap was set at .20mm and the lift on the Intake was .2680" and the exhaust was .2470".  Keep in mind a completely different engine, also this was a freshly done head.   

I took the measurements on the Spring Keeper, the largest flattest place available, keeping the dial indicator as perpendicular to the work as possible. 

Best, 

Mike 

[Adam RocketMoto]

Thanks, Mike. Gives me something to work with if the cams are the same or nearly so on both bikes. 

Also, compression... What's normal? I measured about 92 pounds. Seems low, but maybe because it is low compression engine... Or worn. 

Regards,
=Adam=

[Bill Irwin]

Hi Adam

You are talking about the cam ring.  The other ring is the slip ring - the part that the HT pickup brush skids on.  If this is dirty or stepped it can affect the spark.  I like to start with a new HT lead, cap and plug when looking for ignition problems since these are collectively a common source of problems and cheap and easy to replace.  With a clean slip ring, points and new HT lead see what sort of spark you can throw at the end of the lead when you kick the bike over (plug removed).  If it is less than 1/4" get your mag checked.  More obscure mag problems are incorrect slip ring or cam ring (from a mag that rotates the other way or even in a case I struck from a twin), loss of magnetism, condenser and windings – all for a mag specialist.

I assume that you have some valve clearance and that you don't have a decompressor fault holding the exhaust valve open.  Your cam ring wear and even worn cams shouldn't affect slow running much.  Timing of spark and valves would though.

Cheers Bill

From: Adam RocketMoto <ad...@rocketmoto.com>
Reply-To: "guzzi-...@googlegroups.com" <guzzi-...@googlegroups.com>
Date: Sunday, 25 August 2013 11:00 AM25
To: "guzzi-...@googlegroups.com" <guzzi-...@googlegroups.com>
Subject: Re: [guzzi-singles] Airone info

[Adam RocketMoto]

Bill:

Yes, it's the cam ring that is worn in the 'points open' section. 

I will inspect and clean the slip ring. Will replace with a new copper core wire and non-resistor cap, and a new plug. I had checked the the spark with a spare plug, where I bent the ground electrode about 1/4" and the spark seemed OK. 

Valve clearance is set to .002" (.05mm) intake and .012" (.3mm) exhaust. Compression check holds at 92 pounds (is that low?) and doesn't leak down, so the exhaust valve isn't staying open. 

Regards,
=Adam=