DellOrto SS29 carburetor issues

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Alan Comfort

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May 27, 2025, 10:24:29 PMMay 27
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My Falcone is fitted with a DellOrto SS29 carburetor. It has recently started to spit raw fuel from the bell mouth. In the past some slight spitting was occurring when the engine was first started and running slowly. It did not spit when the engine was at operating temperature. It now spits at all engine speeds. No difference is noted when running with the air valve open or closed.

This afternoon, I dismantled the carb and cleaned it in the ultrasonic bath and blew out all the passages with compressed air. The float appeared to be in good condition and the clip was in the float needle notch. The float valve seats well. I forgot to check the throttle needle position, but it has not been changed since the carb was working well. The throttle slide shows no wear and fits the bore without excessive play. When I re-assembled the carb and installed it on the bike, it started easily and ran well, but there was no improvement with the spitting issue.

Does anyone have any suggestions regarding this issue?

Ciao, Alan in Roberts Creek


RICHARD YAMANE

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May 28, 2025, 1:36:50 AMMay 28
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You might want to check your valve clearance.

Rick Yamane
Importer of Vape/Powerdynamo ignition systems and Polisher of bikes at Motion Pro

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Patrick Hughes

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May 28, 2025, 1:49:20 AMMay 28
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I had that issue and it was ignition timing. The  gear had slipped on the taper shaft and there was no key in the shaft. I reset the timing still no key and it runs fine.
Patrick in the UK

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From: 'RICHARD YAMANE' via Guzzi Singles <guzzi-...@googlegroups.com>
Sent: Wednesday, May 28, 2025 6:36:45 AM
To: guzzi-...@googlegroups.com <guzzi-...@googlegroups.com>
Subject: Re: [guzzi-singles] DellOrto SS29 carburetor issues
 

Alan Comfort

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May 28, 2025, 3:58:00 AMMay 28
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Valve clearance was the first thing that I checked...all good. Good compression and excellent leak down test results. Next is ignition. As they say, most carburetor problems are in the ignition and most ignition problems are in the carburetor.

Alan Comfort

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May 28, 2025, 8:47:49 PMMay 28
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Cleaned and adjusted the points, A significant improvement was observed. A strobe light indicates that the ignition timing could use a little more advance. I'll try that later this week and report back.
Alan in Roberts Creek

Alan Comfort

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May 30, 2025, 3:58:38 PMMay 30
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Found the problem. The exhaust cam follower is pretty much destroyed. Not really sure how it ran in this condition, but it explains why there was a gradual deterioration in the way the engine.was running. Glad that I caught it in this stage rater than total disintegration. The cam looks good.
Does anyone out there have a spare exhaust cam follower assembly (11552/M 2082) ?  I can probably get by with just the roller, pin and bushing if I do a little welding and careful filing on the lever. 
Regards, Alan in Roberts Creek
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Mike Peavey

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May 30, 2025, 4:19:19 PMMay 30
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Alan, when the club mechanic for the Italian Falcone Club of Schio that Pat Hayes and I belong to, thank you Patrick for introducing me, was here in Boston visiting last summer, we were fooling around with my Falcone, trying to figure why it was running weirdly. He discovered both cam followers were very worn and sloppy. Two weeks after he went back to Italy, these showed up in the mail. 

IMG_2122.jpeg
It now runs way better. 

Good luck.

Sent from my iPhone

On May 30, 2025, at 3:58 PM, Alan Comfort <alan.c...@gmail.com> wrote:


Found the problem. The exhaust cam follower is pretty much destroyed. Not really sure how it ran in this condition, but it explains why there was a gradual deterioration in the way the engine.was running. Glad that I caught it in this stage rater than total disintegration. The cam looks good.
Does anyone out there have a spare exhaust cam follower assembly (11552/M 2082) ?  I can probably get by with just the roller, pin and bushing if I do a little welding and careful filing on the lever. 
Regards, Alan in Roberts Creek
<DSC_1105.JPG>

<DSC_1106.JPG>

                                     

Patrick Hayes

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May 30, 2025, 4:20:15 PMMay 30
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On 5/30/25 12:58, Alan Comfort wrote:
> I can probably get by with just the roller, pin and bushing

Alan: These rollers are a common wear and replace item. No need to
mess with the lever itself. Also, there should be a spacer washer on
the pivot shaft between the two levers. I can't see if you have that.

Remove the lever.
Grind the end of the roller axle flush with the lever.
Drive out the roller axle pin.
Reverse with new parts.
You will likely find that the axle pin is hollow (at least on the ends).
Use a flaring punch to spread the axle pin and lock it into the lever.
Grind away any excess so that the roller axle pins don't abut each other
in operation.

Patrick Hayes
Fremont CA

Alan Comfort

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May 30, 2025, 4:55:38 PMMay 30
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Hello Patrick,
The spacer between the two rollers is present. The inner faces of the lever are badly worn, but a touch of weld and some careful filing should pit it right. The intake roller is OK, but I will replace it as a matter of course.
I have contacted Guzzi Retro to see if they can supply the parts.
Ciao, Alan

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Alan Comfort

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May 30, 2025, 9:46:41 PMMay 30
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Found the parts at Guzzino in California. Should be back on the road in a couple of weeks. I guess the old loop frame V7 will see more use in the interim.
Alan, in Roberts Creek
5E8D6C50-10F2-4AEF-A434-4C0AE36BC463_4_5005_c.jpeg

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