Ducati Monster Forum

So this relic followed me home last weekend (literally, on a trailer), a 1966 Sears 250 Twingle.

It was my Dad's, and has spent the last 38 years crammed into the corners of various garages and sheds, covered with rugs and old blankets, until now. I plan to just get it cleaned up and fully detailed and get it running again.

I vaguely remember it running last when I was a kid. During the late '70s and very early '80s my Dad had several Honda SOHC 750s, an old BSA chopper, and this thing (last time this one was tagged was 1981). Some brain donor pulled out in front of him on one of the Hondas and he t-boned their front fender and racked up a leg pretty badly. After that he gradually sold off all the bikes except this one and never rode again. I'm not sure why he kept this one.

By the look of it at a glance, about all I need is a throttle cable and to rid the carb of the inevitable goop and get rid of half a tank of incredibly nasty gas....

 (https://i.imgur.com/ihEkEfF.jpg)

Be mindful of the crank seals. If they leak, it will suck air and seize.

Good call, especially after this much downtime.

Oddly, the tires are in amazingly good condition, tubes hold air just fine.

Maybe no electrical equipment in these garages and sheds. Electric motors create ozone.

Nothing but your basic lights, garage door openers and such.

That is exceptionally cool.

 Built by Puch they are relatively reliable. sadly Ducpainter is right and those crank seals are a must.

The seals are available, we'll see how much of a PITA they are to replace. Wonder if I can luck out and swap them without tearing the entire engine down.....

After that period of time I would toss the tyres and tubes regardless of how good they may look.

Most...and I repeat...most 2 stroke crank seals are replaceable without splitting the cases.

You'll need a puller for the flywheel, and possibly the primary gear.

I'd see if it runs, before I did the seals. You might need to do more, and if the cases need to be split, I wouldn't want fresh seals in there while taking things apart.

Yeah, the initial plan is to clean the carb, points, and plugs then see where it goes....

Winter project, since it's just around the corner.

Got bored over Thanksgiving weekend, so I finally tore into this thing a bit.

Pulled the carb and stripped it to find that it was remarkably free of crud. Gave it a good soak for the better part of a week and put it back together, all passages are clear, should be good to go there.

I wish the 'remarkably free of crud' comment could also be said for the gas tank. There was so much goo down deep in it that I couldn't get more than a drop of the nasty old gas to come out with the crossover tube banjo bolts and the petcock completely removed. Yes, you read that right. I dumped in about a gallon of E85 for a solvent to mix with the old gas and started ramrodding the holes with a bamboo skewer to get the flow going. From what I can see down the cap hole there's just some fine rust sediment left, along with a little black goo. I had the black goo drooling out of the bolt and petcock holes, and it is the strangest thing I've ever seen in a gas tank, like thick plasticky tar that looks and smells completely evil. Next I plan to try and scoop out anything I can reach through the cap hole from the bottom, plug the holes, refill with E85 again, and drain it again. After it dries out I'll fill it with vinegar and BBs and start shaking. The tank appears to be in pretty decent shape inside otherwise, and appears solid. Time will tell.

So, in closing, if anyone needs a couple gallons of E85/mystery goo, I'm your guy. Would probably make good bonfire starter.....  [evil]

 [thumbsup] Fire starter goo. 🔥

Ditch the E85 and get some MEK. [thumbsup]

Yeah....been thinking about something a little more aggressive, but the air in my shop is probably toxic enough at the moment. Don't really want to risk damaging paint either since I want to keep this thing original.

Here's the black goo that's drooled out of the right side crossover tube hole onto the paper towel. The globules have solidified completely. Weird.

(https://i.imgur.com/xQSmI59.jpg)

Weird indeed.

I wonder if it's fuel breakdown related. It really almost has to be. I'm guessing this thing had leaded gas in it, and after almost four decades of sitting, who knows?

Usually all you have is very varnishy gas and a little tank rust. This is a puzzler.

Premix

These weirdos don't utilize premix (other than for initial break-in), I was shocked to read this in the manual. However, that doesn't mean that there wasn't oil mixed into that tank.

I'm wondering if it's a concoction to prevent tank rust.

Certainly isn't regular gas shit from the era.

Cars from 50 years ago with leaded fuel start right up.

That stuff didn't seem to go bad.

Wut
------------
EDIT They're oil squirters like Yamahas, yes?

Said there was an oil tank 'in' the gas tank?

If my memory is accurate they had oil injection.

Howie's right - the manual states explicitly that no premix is used unless for initial break in, they suck oil from the front of the left side of the gas tank (hence the two caps). The throttle also runs a cable that regulates the oil pump feed. Pretty amazing stuff considering they were making these starting in 1953.

Still mystified by the gas tank. Flushed some more with E85, pulled the tank, drained, let it dry out a while, thumped the tank like a bongo over and over, and got piles of nasty powdery crud out of the fill hole. No more black mystery goo. The amazing thing is that from where the fuel level was downward the tank metal is pristine and shiny. Too bad the tank wasn't full to the top.

dp might be right, but I'd be surprised if anything had been dumped in it as a preservative. But, I can't imagine things would be as rosy without something in there all this time. Who knows. Now I'm waiting for traces of residual gas/liquid to dry out thoroughly and it's time for the first (dry) round of BBs to loosen up anything else before I start the vinegar regimen.

Changed plugs in it too since the tank is off, the rearmost plug is basically impossible to remove with the tank in place. Plugs were nice and squeaky with light thread rust. The rear plug was marked "Allstate" and I'm guessing it was original to the bike since they sold these bikes as Allstates prior to '66. I need to make up some new battery cables and will be able to see if this thing has spark soon.

(https://i.imgur.com/65ZOrCV.jpg)

For future reference, the tried and true 'fill it with vinegar' method works very well. However, there's an allegedly environmentally safe product out there called EvapoRust that is even better. The stuff is amazing, and I followed up my vinegar soak with this stuff. Leaves rusty steel like new as you can see. I've been soaking various external bits of this bike in the stuff with great results.

Up next I get to play upholsterer and redo the seat cover, which is so dry rotted and cracked it can't be saved.

(https://i.imgur.com/akPn02u.jpg)

The old girl cleaned up pretty well. She's got too much precious patina to violate it any further than my thorough cleaning. [thumbsup]

Recover seat, check. Fab new battery cables, check. Verify static timing, check. Test for spark, check. Fab and fix missing rear gas tank mount, check. Test for gas leaks, check.

When I went to check for spark, it was pretty damn cool to hit the key and have all the lights come on for the first time since 1981. All signs point to this thing running as soon as the snow is gone and I can get it outside. If it runs well, about all it will need is tires and plug wires. Game on.

Looking great!

Wow!   :o  That looks awesome.

Well, we had a beautiful spring day in the low 60s on Saturday before snow came back for Easter, so it was time to wheel this beast out and see what's what.

Three or four kicks, bam! Runs like a top, idles nicely and almost silently. I put three miles on it puttering around the neighborhood on the ancient rubber, no drama, everything works. Starts on one kick when warm.

Time to get some new tires ordered so I can ride this thing for real.  8)

(https://i.imgur.com/PufU5w8.jpg)

Nice!  Looks great.

That's awesome, Dave. [thumbsup]

Very cool!

When are the Toomey pipes arriving?

Haha, Toomey pipes would be awesome.....  [evil] There were accessory pipes available for these, but apparently they've all vanished off the face of the earth like most of the bikes.

I ran across these pics a while back online.....if mine hadn't been complete, something like this might have happened.

(https://i.imgur.com/2q9MvT2.jpg)

(https://i.imgur.com/1I22rGJ.jpg)

I'd consider coming out of retirement for that. :P

I gots a rear fender that needs a 2-tone job.  ;D

For some reason, that isn't getting my attention. :P

Figured since Nick mentioned Toomey, that I'd drop this here... http://kawatriple.com/denco/dencocatalog.pdf

This really came out nice!  I don't know much about two strokers, does this just not have expansion chambers?

They're weenie little muffler expansion chambers, not proper pipes.

But actually they're just fine for this moto.
Don't really want to be torturing the engine with more HP as replacement parts must be thin on the ground.

I suspect the entire cylinder is cast iron, yes?

Well, if a magnet sticks to it, it has iron of some amount. So that covers iron, steel and 400 series stainless steel, among others.

Iron would make the most sense.

I'd add 347 stainless.

It's far from a complete list but I didn't know about 347

I ran into it when I was working in the fab shop.

They used a big piece of it in a camera base they made for the Smithsonian. I just painted the thing. The whole weldment was 8 feet across.

Yep. Replacement engine parts for these are slim to none, even from the one place in the US that is considered the source....

The cylinder is indeed cast iron.

1967 model

https://www.bike-urious.com/no-reserve-1967-sears-allstate-puch-250-twingle/

 8)

I've been buzzing around the neighborhood on mine here and there since the initial resurrection. It's sorta fun to ride even though it's not high powered by any stretch and cable operated drum brakes are plenty sketchy. Part of the fun I guess. Going to get some tires ordered for it soon, since it's going to need to venture out on the road as it should.

I feel like the old tires would be the sketchy part ;D

If you intend to ride it more often, you can get shoes turned to round for each drum.  From the drum brake crowd, that seems to help.  Well, somewhat.

I'm sure. Baby steps.  :) Tires first.  ;D

From what I've seen, brake shoes don't exist for these either. You basically have to send old ones in for relining at a semi-obscene cost. And these things aren't especially valuable.....

When I had my S2, I'd buy linings by size, and rivet them on myself.

If the linings are bonded, you can do that as well.

There are sources for linings.

http://www.bmacinc.com/wp-content/uploads/2018/02/Relining-Motorcycle-Brake-Shoes-1.pdf

Lining is riveted on these. Thanks for the link, I think I'll need to scrounge up a set of shoes off eBay and redo them as time permits and then swap them out when/if the time comes.....

Just because the OEM lining was riveted doesn't mean the replacements need to be riveted...just sayin'. ;D

The adhesives made today are far superior to the stuff from the 60's, and might possibly be stronger than rivets.

Very true.....some of the glues/epoxies these days are something else.

I'd use J-B Weld without hesitation.

It's rated for 500^o F constant, and a max of 600^o F.

Those brakes will never get that hot.

An advantage of riveted is they transfer heat from the lining to the shoe better.  Just throwing this in, I can't see this being an issue with the Garage Ornament.  Back in the late 60's when I saw bonded lining failure it would be on cheap inferior relined brakes.  The problem I do see is without arcing them break in will take forever.