teach me about a ducati 250 monza

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jaguarsurfer
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teach me about a ducati 250 monza

Post by jaguarsurfer »

i found a 250 monza cheap and i have been looking for a old bike. i think that it will fit the bill. i want a vintage bike that i can ride around town and play with on the back roads
is a 250 monza a desmo?
is it a bevel?
is a desmo a bevel?
is it a "good" vintage ducati?
thanks for any help, im having a hard time finding things out about older ducatis
if you say to someone "penny for your thoughts" and they give you there two cents......what happens to the other penny?...doesnt seam fair
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DesmoDog
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Post by DesmoDog »

The 250 Monza wasn't a Desmo. In general, if a Ducati single has a number on the cam cover, it's a springer. Desmo's have a "D".

Yes, It's a bevel.

Desmo does not equal bevel, nor vice versa.

The 250 considered by some to be the best narrowcase Ducati. But they're all "good" depending on what you want. A lot of 250s were raced, there is a lot of information out there on tehm and parts are available.

There are quite a few books out there covering the older Ducati's. It all depends on what kind of info you're looking for.
jaguarsurfer
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Post by jaguarsurfer »

im looking for "specs"
also performance parts
numbers built
values
if you say to someone "penny for your thoughts" and they give you there two cents......what happens to the other penny?...doesnt seam fair
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DesmoDog
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Post by DesmoDog »

jaguarsurfer wrote:im looking for "specs"
also performance parts
numbers built
values

http://www.ducatimeccanica.com has a lot of info on the singles. Otherwise there are a few books that have reprints of magazine articles from back in the day and listed performance numbers. For performance parts you'll probably want to check with Sy'ds Cylces or Roand and Race or somehwere like that. Info is at the site listed.

Falloon's Standard Catalog of Ducati lists production numbers for some models. I'mnot sure if it lists them for the Monza or not.

Monza's aren't very expensive. The last one I bought cost $500 and was complete but tired. I've seen them go for a couple hundred in pieces and a couple thousand in nice shape. I'm not sure what something in mint condition would go for...
jmwild
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Post by jmwild »

There were two styles of Monza, the early ones looked quite attractive and rounded, and were quite rare, perhaps this style never made it to the US. These are well worth restoring, The later ones were very square. The later Monza had a five speed box, low compression engine and small valves, and a lowish spec cam. Perhaps 85 mph at a push?

Having seen those nice repro top yokes on ebay, assuming they are strong, then say any decent cam, like a Mk3 250, plus a high compression piston, also out of a Mk3 250 or desmo, should sort the engine to 90 plus, but give it a fantastic super revvable performance, and make it sound awesome. I would NOT change the valves or carb. Just use higher comp to force the air through. Next an alloy tank, Vic Camp style fairing, clip ons, home made rearsets, alloy rims off anything, alloy rear fender, fiberglass front.

The advantage of not changing the valves, means that you can rev it like a desmo almost without the worry of valve bounce. The small carb means faster air velocity, run with air trumpet & bee strainer, megaphone exhaust. Keep the points ignition.

The result should be a chuckable flexible engine that feels like an all out racer, but is reliable and hassle free, and just great fun.

My advice is NOT to go for a Mk1 spec engine. Yes it is faster, but you might as well buy a Mk1 to start with.
Nick
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Post by Nick »

I commute to work every day on a 350 Sebring, which is basically a larger displacement version of your Monza. I have also used it to humble a great many modern bikes on the back roads (within reason, of course). My advice would be to ditch the stock carb for a 26mm Amal concentric or Mikuni or Keihin, any of which can be picked up for cheap at a jumble or wreckers. Make a new wiring loom using either toggle switches for the lights and ignition, or buy a all-purpose ignition switch with a key. Convert to 12V (I'm using an old Lucas coil from a Triumph, which fits the stock coil bracket perfectly). Toss the stock voltage regulator and use either an old Jap rectifier or a more modern solid state unit. Slap some decent tires on `er and have fun! If, after riding it around for a while, you really must have more power, go to a higher compression piston. The next step would be some head work and a hotter cam. electronic ignitions are also available, but I've been using the stock point setup for the past ten years with no trouble.
My Sebring is stock but for the carb. She's ugly as sin, but very comfortable with the stock bars and always puts a smile on my face. She runs really well, but the 350 has quite a bit more power than the 250.
Most important: Keep the oil VERY clean and change it at 1,000 mile intervals or less. There is also a magnetic drain plug available for them which I highly recommend. Also, don't putt-putt around on it too much at very low rpm, the big end will last longer if you keep it spinning at a moderately high rpm. Once you get the bike running, flush the engine with two or three oil changes at 50-mile intervals to make sure everything is nice and clean inside. 20/50 semi-synthetic motorcycle oil is good, as is 20/50 petroleum motorcycle oil. Avoid using car oil as it can make the clutch drag. (My bike still has to the stock clutch and it works fine.)
Get a copy of Mick Walker's restoration guide and get the stock manual.
Your in for lots of fun!
I'd leave it stock looking. Start messing around with it and and an interesting example of motorcycling history becomes just another Bitsa.
From probably the only person in the world who rides a Ducati 350 Sebring for daily transportation.
jmwild
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Post by jmwild »

I like Nick's idea of keeping it standard and scruffy. In which case I would keep the little Dellorto carb. If they are not worn, they are FAB carbs, every bit as good as the Amal concentric. If you must switch the carb, go for an Amal. I have never seen a Mikuni or Keihin on a running Duke. My 250 Daytona had a Mikuni half bolted to it when I bought it. It looked so wrong. I binned it when I found the Dellorto in the spares it came with. Going with Nick's idea of not turning it into a Bitsa, forget the 12V conversion too, unless you ride at night. The 6V will start and run the bike perfectly, as will the original points and coil. It has been suggested that running a full wave rectifier can make a huge improvement, doubling alternator output, allowing you to use a more powerful 6v headlamp. If you suck more power out of the alternator, it will cost BHP as extra drag on the magnets of the flywheel. I use NGK B7HV plugs, the V means it has a tiny tip that makes it start more reliably when flooded. I actually fitted a scruffy 160 Monza tank on my Daytona, as I was worried about damaging the original tank, or making the bike look too flash. When I stopped using it as daily transport (yes the 6V was bad at night, the wires were thin) I refitted the larger mk1 style tank and noticed how much heavier the bike was with a full tank of fuel.
Nick
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Post by Nick »

Actually, my Sebring ran fine with the 6V set-up, I just switched to 12 because I had some free time and an old 12V coil sitting around. Didn't notice a big improvement in performance, but I've got real nice lights now.
The carb is another matter though. No question, the Mikuni looks out of place on the Duc, but the performance difference is huge! Way more power, better starting, good idle, etc. If you don't want to use a Jap carbie, then use an Amal Concentric. Wrap the old DelOrto in a plastic bag and store it for the day when your Duc becomes a piece of pretty but dead garage furniture -- like most of the other wanker Duke singles that turn up in the bike shows!
Also, don't confuse the low price for which Duc singles can still be found with the quality of the machine. Electrics aside, the Duc single is a very sophisticated and very well-engineered engine. Some modern singles put out more power, but almost without exception, they're nothing but mass-produced throwaway bikes.
From probably the only person in the world who rides a Ducati 350 Sebring for daily transportation.
jmwild
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Post by jmwild »

About the small Dellorto, I have never had a bike start easier, idle more smoothly, use less fuel, and pick of from low revs better than with its tiny dellorto, something like 20 or 22mm on a 250! Perhaps with a bigger, worn dellorto carb things are different?
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Post by droopydawg »

Glad I found this original posting.
I am a newbie on here as I just acquired a 1960-something, Bevel 250 scarmbler barn find in Georgia for $200.00.
1. How can I tell what year it is? The lable on the steeering stem says 196, bit the last digit is not there.
2. Also, I have the oil drain bolt out to drain the oil. What and how much do I put back in?

Thanks, I will be back as I have questions and time to dive into it more.
Nick
Diana
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Post by Nick »

Don't mess with the bike until you get a manual. The manual has all the information you need to take proper care of it. Try to do it on the cheap and you can very easily ruin the bike or wreck a lot of expensive parts.
From probably the only person in the world who rides a Ducati 350 Sebring for daily transportation.
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DesmoDog
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Post by DesmoDog »

Nick wrote:Don't mess with the bike until you get a manual. The manual has all the information you need to take proper care of it.
+1 on that. a manual ill be the best money you spend on any project. If a manual is too expensive, don't start the project...
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