Doodlebug Stretch Finished...

Noseoil

Terrible Tim
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Found a $25 Doodlebug, so I'm starting a build for fun. Plan is to make something to run fast for fun. Here's the original bike & a few shots of the work in progress. I used 7/8" DOM tubing & slugs to put it back together.

Still a lot to do, but it's a start. Lots left to do, little by little...
 

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Terrible Tim
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Did a couple of gussets to stiffen the frame a bit up front. Will be moving the motor to the rear & getting a new plate for the mount.
 

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Terrible Tim
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A few more progress pictures...







It's running now, but idle jet on the Chikuni is too rich, so I'm waiting for idle jets to get the tuning correct.
 

pearl111

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Nice bike good job I like it. Just wondering with that back sprocket is it hard to keep the front wheel on the ground?

I have a doodle bug with a pred. 212 and a 70tooth sprocket, but right now I'm putting a 62 sprocket on because its hard to handle cause the front wheel wont stay down. Even at low speed if I hit the gas hard the bike wants to flip me off the back.
 

Noseoil

Terrible Tim
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With the 10 tooth front & 48 tooth rear sprocket, it's an easy ride. The extra 8" in wheelbase, 4.8:1 gears, clutch which locks up at about 3,000 rpms makes for a smooth ride with no wheelies. A torque converter would be different.

Top speed should be about 65 mph, but I need to actually clock it to see where I am with this setup. If the top rpms I can turn are 7000, that makes for 65 mph with a 15" tire. I'm not as good off the line with these gears, but I have a better top end, which is what I wanted for this build.
 

Noseoil

Terrible Tim
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Here's how it looks now, still a few things left to do, but it's getting there. Need to take the slop out of the steering now, add a damper & make a few more adjustments. I guess it's never really done until it's gone....



 

Noseoil

Terrible Tim
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OK, I got some bronze bushings from McMaster-Carr to fix the steering slop problem. Here's what I did. First, used a step drill to open up the holes to 1/2" from the original size, about 10mm, but they were pretty sloppy after years of riding.

Drilled.jpg

Next, I drilled out the bushings to 10mm (had to order 3/8" ID X 1/2" OD flange bushings) & pressed them in place. Snug fit, but they went in well enough. Set them to take out some of th vertical slop but still had to add a couple more washers. With the new bearings they are nice & tight now.

Bushings.jpg

Put it back together, did some paint touch-up to fix a few nicks & scratches from the work. The 8mm hole on the bottom spreader is for the steering damper. Still need to weld a tab onto the frame for the mount.

Front-S.jpg

That's it for this week, waiting for the damper to arrive next week. Will post the rest of the mods next week, almost finished now with it, I think?
 

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Couple more pictures. New 1/8" SS brake disc & steering damper arrived early for a change...

NewDisc-s.jpg

Damper-s.jpg
 

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Also, the tires were both very slow leakers somehow, but would lose air over about a month. Never did find an actual cause. Counld have been the stems, beads or pin-holes somewhere. I went to a local cycle shop & bought some sealant, so hopefully that problem is solved now. We'll have to see how it works.
 

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This is all it will do with this motor, but it's fast enough for an old guy who rides, don't want to go faster any more. The red bike does a bit better than this, but ..TopSpeed.jpg
 
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