Doodlebug - Stretch

noseoil

Active Member
#1
Starting a Doodlebug build. I found a "used" Doodlebug in town for $25, so I grabbed it. Here's how it looked when I found it, a bit rough, but for the money it was a good deal. The main stuff I need is there, the rest I'll have to figure out as I go.
DB-Bought.jpg

Stripped it down & did a chop for an 8" stretch,to make a bit more room for the motor inside the frame.
Frame-Cut.jpg

Made some DOM extensions with 5/8" slugs for the stretch.
8-ext.jpg

Clamped with 1" angle to keep things lined up.
Frame-Clamped.jpg

Welded back together, need to find a better machine, but it worked well enough.
Frame-Stretch.jpg
Added a couple of gussets at the front.
Gusset.jpg

Next is going to be the engine mount setup. I may take a 420 or 460 in the frame, just for fun. Will post some new stuff, once I think a bit more about the engine choice & setup. I'll be going with a 15" rear tire & 13" front, so there's still a lot left to do, but it's fun thinking a bit about this one & making things work.
 

noseoil

Active Member
#3
Chopped out the engine mount & added a length of 7/8" DOM for the new motor mount at the rear of the plate. Still trying to decide on the engine & final drive system. Since Vegas doesn't sell the 460 anymore, I'm thinking about a stock 420 with a jackshaft for this one to begin with, or a torque converter, but still not 100% sure, so I'm waiting & doing a bit more research for the next part.
Frame-Crossmember.jpg
 

Attachments

noseoil

Active Member
#7
Starting on a motor build, 11:1 head work, 1st attempt at milling one, took off about 0.030" to see how it goes. Had some hand work to clean it up, but shaved & ground on a granite slab with sandpaper, then lapped it on a glass sheet with valve grinding compound. Should be OK... HeadCut.jpg
 

noseoil

Active Member
#10
Hydraulic brake installation today, it finally arrived. They feel mushy, normal for the Tao Tao type, or should I bleed them. They engage pretty far down toward the grip now. Not like the other bike, but a different setup on the Doodle Bug. These are the Tao Tao type with 2 1/2" centers.
Bracket.jpg WeldedBracket.jpg BackTire-1.jpg
 
#12
Noseoil...You must get ALL the air bled out of the whole system from the caliper up to and including the master cylinder piston. If that doesn't get it, next you will have to align the brake pads to the rotor. The easy way to do this is hold a long screwdriver handle against the end of the caliper cylinder while someone applies the brake, hold the screwdriver vertical then horizontal. If the screwdriver swings in an arc the pads are not parallel with the rotor. Bend or shim the caliper mounting bracket to eliminate the arc movement and the brakes will now have a firm feel with minimal handle movement. I had the same problem and the screwdriver trick worked wonders for my disc brakes!
 

noseoil

Active Member
#13
Making progress on the build, slowly. Putting the engine back together & will be a mild mod build.

I did the bleed for the brakes & it was better, but not great. The easy way to bleed the brakes, I hung the master cylinder on a hook up high & let the caliper dangle with the line straight & vertical, then tapped the line once in a while when I walked by. Started to assemble the brakes & the lever is nice & tight now. All's well that ends well.

Eng-1.jpg Assembly1.jpg
 

noseoil

Active Member
#15
Yep, figured it can't hurt to put a plate on the existing mounts to distribute loading on that side of the block. Might help, but might not, it's a crap-shoot at best, so if it fails somewhere, I'll know where it happens. This motor will only make about 14-15 hp, so it shouldn't be a problem (we can't possibly CarbSide.jpg screw this up).
 

noseoil

Active Member
#16
This motor is built with a stock piston, arc rod, PVL flywheel, shaved head 11:1 +- (not really sure as I didn't cc the chamber & cut the piston a bit), ported the head a bit, 22mm Chikuni & Dyno cams Super X cam for the hemi (.265" lift) with 22# valve springs. I did notch the piston top for the valves, as I was thinking there would be a problem with the valves hitting & I don't want that happening at max rpm. Thinking I won't run over 6500 with this setup, but we'll have to see how it all goes together & how it pulls on the top end with 4.8:1 gearing & the 15" tire.
 

noseoil

Active Member
#17
Still waiting for a catch-can, fuel line shutoff, header, clutch cover
Left.jpg Right.jpg & a couple of other things, but progress is being made every day. Here's where it is today. Need to start the seat as it's pretty ratty now. Got some cheap material at Wally's World yesterday & have some foam in the shop, so...
 

noseoil

Active Member
#19
Finally got enough parts shipped up here to Raton to start the bike up yesterday for the first time. It started up pretty easily, but now the tuning starts. I'm running the Chikuni VM22. It's too lean with the pilot jet it came with (the #15), as the air screw on the bottom of the carb doesn't seem to have any effect on the idle/run rpm's when it's turned. With the air screw all the way in, there's no difference in the engine speed. This indicates a lean condition, so I need to get a richer idle jet.

I've sent for an assortment of idle jets which will arrive in about a month, so I'll have to wait to report back on the engine build & performance. For now I'm happy with the bike & how it feels, but it's a dog trying to go from idle to a wider throttle position, stumbling & missing.

Looking forward to reporting back on a top speed with this engine setup, but not until I have the carb sorted out & working as it was designed.
 
#20
That caliper is made for a rotor more than twice as thick. Take another brake pad and remove the friction material then put the metal plate (long one with holes behind the brake pad on the caliper to take up the gap.
Your handle will have less travel and the brake pad wont shoot out while riding.
 
Top