1966 Ducati 250 Monza

DesmoDog

Been Around the Block
Here's my 1966 Ducati 250 Monza, the other part of a package deal with the '66 160 Monza Jr I posted a thread about already. http://www.dotheton.com/forum/index.php?topic=33195.0

This one isn't done yet so it won't be the posting blitz from start to finish like the 160 thread. Judging by past experience I'm afraid this thread could go on for years.

Here's how it looked in the ad;
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This is the bike I envisioned building out of it;
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I got the tank, fenders, and toolboxes while I was building my 160. But then the plan changed for my 160 and I decided to build something more along the lines of a Mach 1 out of the 250. I had traded away my first Mach 1 gas tank so I bought another one off of eBay. The first tank was in fantastic shape. The second one, not so much. Aside from the cut off flanges up front, it looks ok, right?
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Until you flip it over anyway. Someone obviously tried fitting it to a non-Ducati frame with the aid of a hammer. Ouch.
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I put it away and tried to gather courage while I distracted myself collecting other parts. At some point I decided I wanted to upgrade the bike. Bigger engine, better forks, better front brake... while searching for a good deal on a Grimeca I ran across a deal on something a little tastier. I had picked up some flanged alloy wheels from a guy I met at Mid-Ohio, and ordered some stainless spokes from Buchanan's to build this;
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I would have gone with Excel rims but these were a good deal and I was assured they'd fit a stock Ducati hub. And maybe they do. But they don't fit an Oldani replica brake which looks (as in I get the same dimensions when I measure them) to me to be the same size as the stock Ducati part! Grrr... so much for saving money. The spoke holes are just a tad too far off to "tweak" to make work, I'll be buying Excels for it after all.

Over the years I had been stealing parts off the 250 to use on other projects I have. Eventually this became a true basket case. Seeing it all torn apart made me more serious about finalizing plans for it. I sourced an engine out of a 350 Sebring, along with some 35mm Pantah forks (that I've since decided not to use). With the forks, brake, and engine worked out it was time to start mocking it up.

I looked at the tank again. After my failed attempt at saving a tank for my 160, I had to admit to myself I didn't have it in me to save this one either. What to do, what to do... Then I saw this, a 250 that fellow Bevelhead Ken Reece put together. By coincidence it even used the same front hub that I have.
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I loved it. I got in touch with Ken and he confirmed it was sporting bodywork by Evan Wilcox.

A little background - quite a few years ago I spent some time at Evan's shop and liked his work so much I seriously considered buying another bike just so I could buy some of his bodywork. It became one of those "someday I'm going to..." things. When I saw Ken's bike I decided this was going to be the day. I sent a deposit to Evan, and the plan was in motion.

I work in the auto industry. This was all happening right before the big crash. The day after sending the deposit check out, I was told there were layoffs coming. My income was taking a hit. The toy fund I used for my bike purchases wasn't going to be looking good at all. Was this a smart thing to do?

Screw it, I had put this off for too many years and if not now, when?. Damn the torpedoes, full speed ahead! The bashed tank (along with a lot of other stuff) got sold in an effort to get the money together before Evan got to my order and required payment. I sort of made it. The cash was there when I needed it, but my charge card had a balance on it now too. It seems a few other, non-related items got charged instead of paid for along the way. Funny how we rationalize things...

But I was lucky, I kept my job, things worked out. A couple months later I came home to find this in a box on my doorstep;
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Here's how it looked perched on the bike. Don't mind the fenders and shocks and wheels and bars and things. Basically everything other then the tank and tail will be changed before it's done.
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I also tossed it on my 160 project just to see how it looked on a black frame with silver fenders.
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Looks like I won't be using a stock fender with the new tail! I'm not a big fan of the black and silver either. I've got a couple ideas on color schemes but since I change my mind so often I won't post up any ideas quite yet.
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Next step was to mount this stuff.
 
The tank had to be in place before I could figure out where the tail went. Evan provided an aluminum channel that spanned the tunnel under the tank, I made up a bracket to attach this channel to the brace on the front of the frame. I had to be careful of a few things when figuring out where the tank should go.
1) I had to be able to get the mounting studs under the tank into the bracket. The top triple clamp can get in the way of the tank if you mount it too far forward. This probably isn't an issue if the rubber isolators aren't in place but on one early mock up I clamped the mounting bracket into position only to find I couldn't lift the tank off...

2) The bottom of the tank has to clear the cylinder head bolts. I taped some washers on there to make sure there was space between the tank and the engine, hence the green tape in a few of the photos. FWIW the 350 engine is a little taller than the 250.

3) The coil has to clear the bracket. I ended up clearancing the bracket a touch to make everything fit.

Here's a shot of the front bracket in place but before clearancing for the coil;
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And how it all fits together under the tank. The isolator isn't in it's correct position though.
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The back of the tank is supposed to be held up with a bracket (supplied) that has a mount for the tail too. I ditched that and made up a different one. It's just a channel that's been cut to match the frame and then milled out to get everything to the right height. I haven't taken any detailed pics, but here it is in it's rough form, I'll pretty it up before I weld it on to the frame.
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Here's a shot of the bottom of the tail. The front bracket is in place, the rear of the tank is supposed to rest on that. There is another bracket that is supposed to be welded to the frame and then the two rear bolts attach to that. My problem was the fender I wanted to use would block access to the front bolt, so I'd have to remove the fender to remove the tail.
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I moved things around by making a plate to move the rear bracket back even further so I could use the stock mounting points for the seat. The bracket will be bolted to the seat and also bolted to the frame instead of welded. The front part had me stumped. I came up with a lot of overcomplicated designs before I settled on a simple post bolted to the frame and yet another bracket bolted on the front of the seat. The bracket is still rough looking but it works, I'll pretty it up later. The post, rear bracket, and cut fender;
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The seat. The plate will be flush against the seat when it's done, not raised up as shown.
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The plan was to cut it into two sections to allow the tail to fit down near the frame rails. I spent an embarrassing amount of time working out various ways to mount the fender once it was cut. The rear part wasn't bad. Once I decided to go with a one piece bracket vs two separate tabs, I bent it up by hand and fit it. The front was another story. I went through a lot of ideas and at least four different pieces before finally getting something to work. At first I tried to make something that fit flat on the frame rails so there were twists and bends and minor chaos. I'd get SO close to having something, but on the last 10% I'd crash and burn. Then I cut the first "simple" bracket too short. On the final version I bent it up by hand, ground the ends to fit the tubes, then when it was close, instead of grinding them just a bit more I used a body hammer I had sitting nearby to make it fit. Worked like a champ. I welded (bronze welded, brazed, call it what you will) them in and drilled a couple holes. Then I trimmed the fender down and removed the valance panels. (Purists can relax - the fender was damaged before I got it) I still have some trimming to do, on the rear section especially, but I need to work out the taillight and license plate bracket first. Depending how that goes, I may not even use the rear section of the fender.
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Add one NOS Benelli(?) front fender from Vintage Cosmo and a tach mount from Road and Race, and now it looks like this;
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Dang, I really need to clean my basement...
 
After searching for a license plate/tail light bracket and not finding what I wanted, I decided to make my own. In general I try not to destroy original parts, but the one off my 160 was already bent and cracked... so time for a little cut and paste.

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It's not done yet obviously but that's the general shape. It will have a section on top for the tail light and most likely a brace on that similar to the stock brackets but much narrower.

The tail light I want to use was intended as a running light, so it only had one festoon bulb in it. I thought about fitting two bulbs in there but instead decided to try an LED array. The housing is about 2" x 3", the array about 1.25" in diameter. It's dual intensity, which simplifies things. I'm not a photographer so have no idea how to take pics of lit bulbs to show different intensities. Trust me, it's low setting is brighter than the 6volt bulb that was in there, not to mention the high setting. I was worried about small viewing angles of the light but it's not as directional as I expected. It will light up a dark room.

Here's the LED cluster in the general position. More than enough room, I could even go with two (It's bright enough to shine through the reflector part of the lens on top). I'm considering a 1" diameter cluster on top for additional brake lighting.
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And here it is lit up under the lens. This is in a lit room, the camera is compensating for the brightness obviously. I'm kinda bummed you can see the individual LEDs (it's more obvious in real life), I realize that's out of place on a vintage bike but it's a price I'll pay for low current draw and instant on. These bikes are known for having marginal charging systems, but that's likely going to change too so I'm probably worried about nothing.
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I'm not 100% happy with the whole set up but until I find that perfect bracket, this will have to do.
 
A few changes - I added the Oldani replica front brake, clubmans, a tach, and a 150mm headlight. The rims will be switched as already mentioned, and these tires are intended for another project but they keep the rims from getting scratched up.

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I'm rethinking some other things too. The tach may be shelved for a later project - I may try to put an Acewell speedo/tach in the headlight shell? Verdict is still out on that, basically I'm not going to try to make it look "era correct" which was my original plan. A few modern touches to make it work better may not be so bad?

I think the fenders have to go. I'll probably copy what Ken Reece did on the bike I showed earlier. I might go with a different tail light too. And the rear shocks may not make it either... Is it any wonder why these things take me so long?

Latest obstacle is with the headlight. I bought a trim ring, then a shell, and they don't fit each other (the trim ring is too loose). Turns out the aftermarket trim rings don't fit the original shells all that well. I'm still working on how to fix that but have a couple ideas.

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I played around with the geometry of the brake stay. The linkage on the brake plate only allows certain orientations of the plate due to interfering with a boss on the fork leg. I've found two pics of other bikes that have used this brake and they are both set up like this.

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I built a mock up brake stay to mimic that and decided I didn't like it due to the angle between the brake cable (red arrow) and the linkage. This next picture shows what I think is a better set up, solely based on the angle between the cable and the linkage. I admit I may be over thinking this.

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Don't mind the geometry of the brake stay itself, that will change to eliminate the dogleg between the fork mounting bolts and the brake plate mounting bolt. It's also been suggested to mod it so the cable pulls on the top arm instead of the bottom, which would put the linkage in tension rather than compression.

Disregard the dot on the tire. I will be changing the rims and tires on this before it's done, these are just being used as place holders until I have the money to buy the right parts.
 
Roughing out the brake stay. I used 1/4" aluminum.

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Don't mind the dimensions, it hasn't been trimmed down to it's final shape yet. I left the top large so I have material to shape into the fender mount and cable anchor.

I had to buy about four times more aluminum than I needed but it was only about $15 so no big loss. Actually it probably worked out well since I just paid for a front end for one of my back burner projects, and it's going to need a brake stay too. I'm guessing once the fork for that shows up I'll be splitting time between the two projects. Probably not my best plan...
 
Another thing I'm working on is finding a place to put the regulator and the "black box" for the ignition. i'm installing an MZB dynamo from Powerdynamo and the boxes are bigger than I was hoping...

http://www.powerdynamo.biz/eng/systems/7247/7247inst.php

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According to the guy who imports these, vibration isn't an issue so I don't have to worry about using any isolators, which is nice. He also mentioned a lot of guys set them up so a battery isn't needed. I thought the electronic speedo I want to use needed battery power but it turns out it doesn't, which is good news. No battery means no battery maintenance on yet another rarely ridden bike. It also gives me a place to hide the black box (Inside a fake battery box, just like on the 160)

And that's where the project sits as of today. No idea when I'll be making more progress but I'm hoping it's soon...
 
Gonna be another nice build, let's hope this one takes less time than the other... and less time than my GS ;)
 
I REALLY want to get a Ducati single. Used to hang out with a bunch of guys who raced 450 singles back in the day...
 
peteGS said:
Gonna be another nice build, let's hope this one takes less time than the other...

Yeah... about that... I was workign on this on and off while rebuilding the 160, so it's already taken longer!
 
DesmoDog said:
Yeah... about that... I was workign on this on and off while rebuilding the 160, so it's already taken longer!

Hahaha classic... so you should be able to go twice the speed now right? ;)
 
Hey guys, thanks for the interest.

This bike was on the list of things to do, and I had just started making progress on that list, but last Thursday tornadoes came through and we caught the edge of it. I was downstairs with my dogs, working on a couple other projects, when things got a little crazy. Long story short I spent some time wrestling with two golden retrievers, one who wanted to get up onto my lap (no problem) and another who wanted to run to the door and bark at the storm until it went away. (not good).

We got really lucky, There is some damage to the house but we can still live in it, the house three doors down got it's walls/roof blown off and was torn down yesterday. Massive destruction from there on down the block, so we dodged a bullet.

Which is a long way of saying, it may be a while before I get around to working on the Ducati.
 
Swivel said:
I'm not commenting about the bike on this thread.The later 250 single went slow,the 450's were grenades and the 350's were very good.That was then this is now.Don't bother with an obsolete over stretched design that started as a 100/125 and they just kept making the motor bigger and bigger until it was underengineered and over stressed.Like an elephant,good to look at but you don't want to own one.

FWIW the 160cc and smaller engines don't share all that many parts with the 175cc and larger engines. Similar designs for sure but two different "families" as it were. The rest of what you've you've said about the 250/350/450 sounds like what I've heard before. (My 160 is the only Ducati single I've ridden, so I'm no expert...)
 
I'm in. Take as long as you need to keep on doing it right.
 
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