Micargi Puma with twin 97cc flat top lifan's

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azbill

Active Member
May 18, 2008
3,358
5
38
64
Fountain Hills, Arizona
I have 27,000+ miles on my micargi stretch frame (mustang) !!!
I ride it a lot and work it very hard pulling the trailer,,,no probs yet (knock on wood) :)
not all of them crack ;)
 

LabRat

New Member
Dec 24, 2011
596
20
0
Ruston, Washington
Not a lot has happened on this build this week. I have gotten to the point where I am sourcing a solution for the chain tension on the #40 roller chain that will keep the cranks lashed.

And I have been reading on the fourm and scratching my head about on the intake. Just that I have not committed to the material type for the intake, round, square, steel, copper etc.

Soliciting ideas on the how to keep the crank chain tight. I have posted below some of my thoughts with prices of the items shown in the attached photos.

If anyone has had experience with these types of solutions good or bad state your case and/or offer advices. A bracket to hold said solution will need to be fabricated as well.

1)17T 1/2 BORE 40P IDLER SPROCKET
www.surpluscenter.com $9 or local Grainger $19; the Grainger product (not shown) looks superior.

2) FENNER DRIVES FS0071 Self-Adjusting Tensioner,40 ANSI Chain
Deflects Up To 45 Degrees Either Side Of Its Neutral Position Allowing A Pretension Force That Self-Adjusts An Idler To Everyday Elongation Of Chain Or Belt While Dampening Vibration In The Drive with a force up to 30 foot pounds. $84.00 ish online or Grainger

3) From eBay motorized bicycle chain tensioner roller hand made wheel black made usa !! heavy duty chain wheels / rollers they are made by turning down a medium / hard poly urethane skateboard wheel (not plastic) and come complete with sealed bearings, price is for 1 roller. From Seller, " i havnt had 1 wear out yet these are by far some of the absolute best rollers out there !! " cost $10
 

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LabRat

New Member
Dec 24, 2011
596
20
0
Ruston, Washington
Doing it in copper. Dual plane intake. See pix. I think my drill is going to die, seen smoking.

Never did any of this before now. Read about how to on the fourm. The following is what I did. The pictures are how I did it.

Reciept $21

Later I needed to buy silver solider and flux add $16
 

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Wickedest1

Member
Oct 31, 2012
688
7
18
42
connecticut
That's primo lab...fantastic work...you've inspired me to try my hand at something custom...idk what yet but something...thanks a ton
 

Crazy Horse

Dealer
Feb 20, 2009
1,153
4
36
USA
Paging!!! Dr. LabRat to OR( Operating Room ), STAT.

It's ALIVE....................

You my friend are my kind of Twisted, your build is outta sight MAN.

It's almost unfreaking believable, just say it can't be done and the Dr LabRat can make it happen.

Whats better than a one engine build?

Answer:
Double the pleasure double the fun, LabRats twin engine build.

C.H.
 

LabRat

New Member
Dec 24, 2011
596
20
0
Ruston, Washington
Well, I cannot stop looking at it (twin puma) myself. I've been standing there looking at it. Having nothing to do, not working on a thing, I have been out to the shop and just stood there and pet it! (Yes, usually the engines and I talk to them as well)

Ok so I have added some extra bends to the intake so the carburetor is not 90 degrees out into my leg. This setup looks great! Downside is the choke lever on the carburetor will interfere. It can be trimmed not a problem.

The 22mm clone carb I chose has a plethora of bad press* on a pit bike forum. All advice there is to ditch it and get a 'real' Mikuni also advised to use a 28mm carburetor as well. I am looking into this. Found one on eBay full to the hand throttle with the cable parted off a dirt bike $100 complete. This price seems fair from what I have gleaned on the net. At this point I wish I had a ‘real’ one as I see they clamp on not bolt on and I am currently in build a flange @#&^, keep reading.

*However, read on another or same forum and find an equal amount of threads supporting what already I have. Any pointers speak up!

Did someone ask me about is it legal, this bike? Well since I live in Washington State, nothing is. NOTHING* so I will continue to hope the local law is as impressed with my building as they have been the last three years. By this I mean they (cops) talk to me like professionals; who like mechanical stuff, a few have asked if I mind if they photograph my bike and one uploaded to his Facebook page while he was talking to me. Never considered I would be riding this one much, its over the top, I know. Ok, so I am going to ride it. <shrug>

* All gas powered bicycles are by default illegal in Washington State and have been since Dec. 2011 when the 'greenies' in Olympia had all gas references removed and put in place e this and e that. This topic is for another thread. And do - anyone - correct me if I am wrong.

Note, as an Arts and Science major I have never worked with my hands. The method shown that I chose to measure and cut a flange for the clone looks nice, it will not work, do not try this. No don’t, lost a few hours here and used most of one HF saw drill bit. I was really impressed with myself at the time. What I did was press a piece of paper to the back of the clone and rubs my dirty paws on it to make an image of the clone’s intake. Thought it be a nice way to make a layout, makes for a great visual. After making three in steel I quit. Dollar store has protractors and a compass. Get one and mark your points!

The pictures are worth a 1000 words if I do not post them now I'll start ranting about anything so here is where I stopped with the additions to the intake. Add another $4 to the cost.

The drawing on the cardboard is me sorting how to grab the power from the engines. My first thoughts were to have two sprockets on one shaft. The more I thought about it the less I liked the idea. Now I have inked up something I seriously like!

And shown the truth to how I often fund my project/s. Last Friday scored $300 this Friday $400. http://www.emeraldqueen.com/ located in Tacoma 6 miles away. Today’s win will fund the front and rear hub and parts for the jack shaft.
 

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LabRat

New Member
Dec 24, 2011
596
20
0
Ruston, Washington
Looking good LR. Open the drill up to see what died?
Oh yeah that, President of our motorized bicycle club left it here. I'm not telling him. Think he will find out? Pictures are here and on Club's FB. LOL Fun part is he left it because mine does not tighten down well. So his burnt up and I used mine to finish the work anyway.

We will all have to wait and see what happens to the jig saw he left when I get to using that on the chopper forks.

In the end, no doubt I'll be replacing his drill - still waiting for him to see it on FB. Its much more fun for me this way -letting him find it out online.

Thanks for following. Hope to get back to it. As we all suffer waiting on parts. Myself waiting on JS parts and etc. Lot of parts to order still, wheels to build etc. Trust me I am commited to seeing this one through.
 

LabRat

New Member
Dec 24, 2011
596
20
0
Ruston, Washington
I will play with it and see what sounds most awesome!

Man I can not wait.... so much fun with this build. And ideas for others.....

Thanks for following DaveM
 

LabRat

New Member
Dec 24, 2011
596
20
0
Ruston, Washington
Sometimes you can use a large washer as found at good hardware & farm supply stores to make a flange...

They’re thick and the 3/4", 7/8”, 1”, and 1-1/8” id holes can save a lot of drilling!

-Kirk
Saw this a few days ago. Thanks for your tip Mr.B. Got a bit of time today so I''m on it!

Cash impaired for JackShaft parts. Typical of most of my projects. Oh all of us can assemble a bike in one day alright, just seems to take months to aquire the parts.

Did not help when I purchased another 50s Monark this weekend. Nearly a complete bike too. Just missing the horn tank and chain guard.

And it also does not help that on March 24th is the 25th Annual Seattle bike swap; that free event is sure to strip me of all liquid funds.
 

wayne z

Active Member
Dec 5, 2010
1,743
5
38
louisiana
This is an awesome project! From my experiences, I might suggest that you will get much longer service and way less wear and noise from the engine coupling chain, if you go with much larger sprockets like 16 or 20 teeth each. The chain won' t be bending so tight and working so hard and last about 5 times longer. Way less friction too will mean more power to the ground.
 

buck0

New Member
Apr 24, 2011
376
0
0
Orange County, Ca
I've heard twin r/c nitro trucks before and they sound awesome while running, this build is sweat and I'm sure it'll sound sick! Nice build man!! I can't wait to see it complete.
 

motorhedfred

Member
Jul 31, 2009
421
17
18
United States
This is an awesome project! From my experiences, I might suggest that you will get much longer service and way less wear and noise from the engine coupling chain, if you go with much larger sprockets like 16 or 20 teeth each. The chain won' t be bending so tight and working so hard and last about 5 times longer. Way less friction too will mean more power to the ground.
LabRat, you and Wayne might be talking about different things. Wayne's talking about the connection between the engines. Because you're looking at jackshafts, I assume you're talking about transferring the power back to the wheel.

If you use a belt to connect the two engines, it'll work but they won't stay in time relative to one another very well. The "most awesome" sound you were refering to will drift in and out of phase as the belts slightly but inevitably slip. Also, after looking at these, they might have bronze bearings in them. Not a terrible thing, but less durable and higher friction than ball or roller bearings.

MHF
 
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