Cheap intake manifold fell apart? This'll get you home.

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daf

New Member
Mar 11, 2014
14
0
0
Ann Arbor
Ahh Memorial Day. A day for celebrating freedom. And nothing says freedom like riding through the countryside on a sunny day with the wind in your hair.

And after a week of rain and misery or broken/missing bike parts, I was ready for that. A nice day. A tranquil day. A no $@*#ing around with my Grubee motorbike day. Well ready sometimes isn't enough. Yesterday was no exception.

Somewhere 15 miles down the road, she suddenly got speed out of nowhere. Next thing I know I'm approaching my current max out of 33 MPH and that was on a downhill..this was flat terrain!

(Now I don't know why I just enjoyed the performance increase instead of stopping and figuring out what had changed. Sometimes you don't think about these things when you're gleefully bunny-hopping Detroit's crater-sized potholes (or possibly pothole-shaped craters, the jury's out) and sucking up the adrenaline.)

I should have looked. My enjoyment lasted approximately 6 miles before the entire pony ride came to a fizzling halt. There, still dangling back and forth between my legs from the momentum like a pair of cast aluminum..well let's just say the carburetor was dangling from the fuel line and indecently placed and leave it at that. :oops:

The intake manifold was cracked into three pieces. The two bolt hole flanges and a tube. 8 miles from home in the middle of bum<BLEEP> nowhere with a crescent wrench and a multi tool to work with. What I needed was a CNC machine, a parts bike or a miracle. That's when I saw the Foster's can lying in the ditch.

Now I grew up making toys out of trash. It's all we had..and where one man sees a beer can, I see a versatile source of materials. I took the pocket knife out and cut a large rectangular section out of the middle of the beer can and rolled it up as tightly as a could. I then made four slits on each end of the tube I'd formed and folded them down to form flaps.

For the carburetor side I removed all of the flaps except two. One top and one bottom. then I slipped it through the leftover broken tube from the manifold. It looked like this when I was done. (Except on the side of the road..not in my kitchen.)



Then I bent the two flaps (on the carb side) down to keep it in place, and inserted it into the carb outlet.

It looked like this:



Then I centered the beer can tube over the engine's intake port and made sure the flaps weren't covering the screw holes. It looked a lot like this:



Then I attached the flange pieces from the broken manifold over the top of the beer can flaps to secure it in place. Like this:



She started right up, and with a little minor adjustment to the tuning..didn't give me any problems. I made it home and stopped by the liquor store for a cold beer. I passed up my regular brew in favor of a Foster's green can.

I figured I owed em one.

Happy Memorial Day!

Ride fast, ride hard and get home safe,

daf
 

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Davezilla

New Member
Mar 15, 2014
2,705
10
0
San Antonio Texas
Yup... lucky you made it home, but without trying to make something it would have been pedal power all the way... Good thinking and glad it worked...
 

daf

New Member
Mar 11, 2014
14
0
0
Ann Arbor
Oh I'm lucky alright. Lucky I watched Macgyver as a kid!

I'm still riding it like this until the replacement part arrives. She's running GREAT. I need to put some sort of adjustment screw in the beer can tube so i can adjust the fuel-air ratio. :D
 

maniac57

Old, Fat, and still faster than you
Oct 8, 2011
4,484
22
0
memphis Tn
Sounds like a typical chinagirl....too rich from the factory.
It started running better due to the air leak leaning out the mixture.
Once you get it fixed. jet your carb properly and it should run like that ALL the time even when NOT broken.
Mine needed jetted three sizes smaller...but all are different.
I drilled my own jets due to the size issues. Buy three65 jets, get three different size holes.
Drilling them myself makes it less hassle to find proper jet.
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
daf, you gave me a much needed giggle tonight. Thanks.

You don't need to be McGyver, just a gear head with a sense of what you need and what you have to make it work.

That was an inspirng story and should be a lesson to every biker who reads it.
You knew what was wrong and what was needed and you made it work with what you had.
Congratulations and thanks for the entertainment.

Those cast aluminum manifolds have been a source of problems for a long time. Order a steel manifold, make sure the gasket surface of the flange is flat and use a good gasket material and you'll be back on the road. Also take Maniac's advice and tune that carburetor a little leaner and you'll be impressed with how the bike performs for you.
Thanks.

Tom
 

daf

New Member
Mar 11, 2014
14
0
0
Ann Arbor
Hey thanks again everyone who piped in on this. The advice and encouragement, especially from veterans like you, is encouraging. This MB is my first and has been an R&D experiment from the start.

I bought a $15 bike off of craiglist (Old Murray..hard front and back..no I mean REALLY hard!) and strapped a King Power (Grubee I'm guessing) 66/80 to it.

Then it was all about riding it hard and often and seeing what broke first.

So far I've:

Lost the muffler endcap (and built a new one out of a soup can lid. That blew out so I replaced it with a beer can top. Boy what's up with me and beer can fixes? Oh yea..plenty of materials. :D)

Rode home on torqued out spokes and ruined a rim. (Yes, yes. I know. But riding that springy back end was challenging as H-E-double hockey sticks and set the hairs on the back of my neck up a bit. I was on a sidewalk in an almost no traffic area, and well..I'm a sucker for that sort of thing..wee.) That led to a lucky find that my girlfriend's '74 Schwinn Suburban's rear hub made for a great sprocket adapter.

Broke a clutch lever. (Snapped right at the thinnest spot. Cast aluminum? Really? In this day and age of high technology? Oh yea..budget kit. Got what I paid for.)

Have gone through 2 sets of brake pads in 370 miles of riding. (Tell me there's something better. Please tell me someone brought auto brake pad materials to the bicycling game! My budget is shaking it's head at disc brakes.)

Decided that a solid inner tube is NOT the best solution for eliminating flat tires in distant lands. SLIME filled tube seems the solution for that.

Decided that short of a custom frame, the NEXT Avalon is the most economical dual springer bicycle on the market that can fit a bike kit and will be the final frame for this project.

Had my intake manifold fall apart and came up with this fix.

This forum has been really helpful and I thank you again for the input.

If you gentlemen have economical wheel bearing and clutch pad replacement recommendations, I'm all ears..er eyes.

Thanks..just one more time,

daf
 
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