Two days ago after 2k miles of riding in the past month I pulled out the Russo Paso for a ride, started her up and warmed he up, filled her up with gas and rode off. 2 tenths of a mile later I was surprised by the most unwelcome sight of flames shooting out from under the front of the gas tank. i had the presence of mine to shut it off, remove the key and set it down on the side stand. Naturally beating at the flames had no effect as the engulfed the area under the front faring. I got on my knees and looked inside at the carbs and pulled off a flaming melted Malossi pod filter, but the burn continued until a calm thoughtful man appeared from nowhere with a chemical fire extinguisher and with one blast the fire was finally out and I collected my self, pushed the bike back to the warehouse. I think perhaps a stuck float or debris in the needle valve at the float bowl on the Del'Orrto 40mm might have stuck causing a flooded carb, but I wonder if that is a decent assessment and I wonder about ignition of the fire. was it a hot manifold, was it the spark of the starter as I moved away from the gas station. I thank you all for any thoughts, suggestions, and ideas regarding both the fuel source and ignition source for the fire as I move forward. I look forward to repairing the damage and riding her again, but I hope to diagnose the problem with some assistance so that she is safe and reliable in the future. Pleas don't give me heck for having the wrong carbs. They came with the bike and they have always performed beautifully. My best wishes to everyone!

welcome to the wonderful world of Del'Orrto

Check the needle and seat and fuel lines

I've been worried about that happening to mine,all that fairing with no way to get inside and put it out.Hope the damage was minimal.Those bowl gaskets on the dellortos have a habit of weeping,but I wouldn't have thought it would be enough to spark a major fire.I'm going looking for a small extinguisher again today ! J.

Hard to tell from here what happened. Could have been a loose hose clamp, or a split line, or the overflow vent was not venting under the engine, or a host of other minor things that happen on a 20 year old bike. Rebuild the carbs, redo your fuel lines with modern fuel injection grade line and clamps, and check it all twice.

Glad your safe, and the bike is basically OK.

Cheers,

Thanks everyone for the help and advice. I will rebuild the carbs, replace the fuel lines and check the fuel tank's overflow check valve and anything else that comes to light. Thanks for the humor as well. The juxtaposition of the words "weeping float bowls" and the photo of the rider on fire is too funny. I appreciate all the support and encouragement and I'll be riding the Paso again before winter begins. Best Wishes! —Randy.

lucky you managed to get the fire off!!

rebuild the carbs correctly and make sure the overflows are connected properly and long enough.

I think you could relate the problem also to :

- POD filters: they get soaked in oil and fuel, then it is just a matter of getting one bad "sneeze" from the engine and they light up straight away.

- Fuel lines, on both my Paso750 and the 907 I did notice that the lines were very long; of course it made easy to move around the tank, but to avoid the lines touching the rear head (or the rear exhaust) I would suggest to cut them as short as possible and fit the "quick fit" fuel connectors as you can find on the 748 - 916

- Age of the fuel lines: they get old and crack often around the clamps; I had a case were a fuel line was incompatible with "advanced" High octane fuels, it would simply get swallen and would start sweatting around a particular clamp. When you replace them just make sure they are 100% compatible with fuels, sometimes the vendors simply sell rubbish...

My Flaming Duc story...

Practice at Mid Ohio on the 900ss, running Malossi's (massaged DellOrtos). Ran out of gas, coasted into the pit. Topped up the tank.

Unfortunately, when the float went all the way down, the little plastic piece that the float hinged on got stuck down. Too tight of a fit. So the carb filled, then overfilled. I thumbed the starter, and BOOM!

Nice thing about the track, there's always a bunch of guys standing around with fire extinguishers...

EDIT: Do the stock Paso's have a fuel shutoff that's easily accesible? I don't know, mine was set up as such a mess that I just ripped out all the fuel lines, and started over with new lines. One of the things I did was to run the fuel line all the way forward, under the headlight, where I installed a 1/4 turn shutoff valve. I did this so I could store the bike easily (I'm gone from home more than half of every year), but it would definitely come in handy in a fire!

what you could do is use an underpressure fuel valve like used on the SS/Monster, many scooters etc.
It just goes in the fuel line and connects to the underpressure/sync tester connection on the carb manifold. I`ve put that on my Paso.
I made two experiences about fuel lines. The first is that many guys use ones with a too big inner diameter i.e. 8mm instead of 6mm. Then they tighten that with a clamp and wonder if one day there`re spills. Second is that the textile braided lines seem the worst to me. They dry up and while you cannot see the cracks in the inner tube the outer part soaks up the fuel and remains wet. They may have their advantages but I prefer other types.

G.

Again, Thank you for the great advice regarding the fuel lines, quick connects, properly laid out fuel lines, easily accessible fuel shut off, and properly rebuilt carbs. I rebuild the fuel system with this knowledge and understanding. The info is probably gonna save the Paso from a second combustion event and heck, it may save me also from serious injury. I am beyond grateful for all the help and advice. Words do not express my feelings. What an excellent community here! I am in your debt. —Randy.

Most Napa(usa) stores carry fuel line with a SAE 30R10 rating. The best currently available and handles all types of fuel inside and outside.

Yeah that's been my experience with quick connects to.All of the ones on my boat outboards have leaked over the years.Unless they have improved them,I would steer clear of them ,just one more thing to go wrong.A couple of zip ties tame my extra long fuel tank line.J.

Well, just an update on my '87 Paso: the Dellorto's weren't weeping, nor were the fuel lines. It was the gas tank which has sprung a leak at the very top. Gasoline will run out of the area at the top of the circumference of the short round steel tube that is welded to the sheet steel which comprises the underside of the tank. That is to say, a micro crack in the weld at the the approx. 1 1/2" diameter x 1/16" gauge x 1 1/2" long protruding steel tube that fits over the small "stump" on the top of the frame is creating the leak.

I just received a POR-15 Kit for motorcycle fuel tank sealing, but I'm concerned that a small can of the sealer won't be enough to coat the entire inside surface of the tank (it's so big!). It seems like I should buy another pint of the sealant to make sure. Do any of you gentlemen have experience with the POR-15 product or fixing tank leaks? I am looking for your advice and opinions before I proceed.

I had a conversation with Lawrence Giardina (the talented Ducati mechanic who did most of the original restoration and
modifications to the bike) of Addiction Motors in Emeryville, CA and he seems to think a reweld of the tank is in order. I' of course don't want to repaint the tank after the weld bubbles and burns the existing paint around the spot.

What about a cold weld fix like JB Weld applied to the exterior at the circumferential area around the tube?

Thanks for your interest and for your time and for any thoughts you may share.