60cc BMX with Vertical Shaft Friction Drive

GoldenMotor.com

turbojoe

Member
Mar 30, 2011
57
0
6
Little Rock,AR
Anyone ever thought about using a worm drive? The worm screw attached to the engine shaft and the roller attached to the worm gear and you would have it at a nice right angle.
 

Dan

Staff
May 25, 2008
12,765
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Moosylvania
Yes Joe! Been looking for one for 3 yrs! Only "perfect" ones I have found are big bucks and cost prohibitive.

Got an old snow thrower and am someday gonna take it apart to see what the reduction is. My thinking is they are already mass produced and a dime a dozen as you can find old snow throwers being scraped or trashed.
 

wayne z

Active Member
Dec 5, 2010
1,743
5
38
louisiana
Most worm gears have a large reduction, and if you had only2 to 1 ratio you would need about a 5" pulley.
. Worm gears won't coast like normal gears,when you cut the throttle,the bike will stop fast.

Easier to find is a 1 to 1 ratio 90 deg box from a mower deck.

Might could adapt one from a small angle grinder, not sure of the ratio though
 

ferball

New Member
Apr 8, 2010
598
2
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NH
Just as a note for lawn mower engines, I remember reading somewhere once that many mowers use the blade to act as a counter balance to the flywheel, and is you plan on running it with out a blade you could/should install a different flywheel that takes into account the absence of the blade. I could be talking out my butt so any one feel free to jump on me and correct me if you know more about this..
 

VlamBallas

New Member
Jun 1, 2011
25
0
0
Johannesburg, South Africa
You are indeed correct dear sir. Though the motor runs without a flywheel, will have to see how it performs under load, before spending some dough on a heavier flywheel..

The build was slightly delayed due to the freeking cold weather, I dont have a workshop and working outside was painfully cold.

Tonight my engine is going on the mount. Had a tough time finding the right material,
 

NEAT TIMES

New Member
May 28, 2008
1,964
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PENSACOLA, FL
Vlam

It is cool having a member from your location and doing a build thread also!! Thanks for sharing it with us. Enjoy.

Ron________________cvlt1
 

VlamBallas

New Member
Jun 1, 2011
25
0
0
Johannesburg, South Africa
Thanx NEAT TIMES,
Though this build is a serious pain in the cheeks most to the time, spend a lot of time swearing at the thing lol, I think its gonna be so worth it in the end.
The biggest pain, is trying to get that blade head? off the shaft, i can get it to budge, not even a millimeter. Any suggestions?

COMPLETELY UN-RELATED
But still fun, My first kit build.
My boss brought the thing to work today, and I volunteerd to put it together for him.
I gotta say, kit builds are pretty shweet, very easy to build. Took me but a few hours to get it up and running.

This is a 66cc, Personally I prefer a little more juice. This one doesn't have much kick.
 

cannonball2

Well-Known Member
Oct 28, 2010
3,682
221
63
Colonial Coast USA.
I have pulled em with a gear puller. Bottom a high strength bolt in the shaft leaving enough bolt above the blade adapter to allow the adapter to move and pull in a normal fashion. Heat helps, but becareful of the crank seal. It also helps to drill a depression in the bolt head to keep the puller centered. Next move is to split it with a die grinder.
 

rustycase

Gutter Rider
May 26, 2011
2,746
5
0
Left coast
I recall, in the past, cutting the shaft above that mounting hub.

Without benefit of an effective right-angle drive, repurposed from something else, I would consider a long belt to make the transition from vertical to horizontal. It does work, and excessive power is not lost.

You could employ a pusher-trailer.

Good luck with your project!
rc
 

VlamBallas

New Member
Jun 1, 2011
25
0
0
Johannesburg, South Africa
Due to the serious lack of funds for this project, I decided to go sponge of the steel and tools at work, and go with the simpler is better approach. Made some good progress today:dance1

Drilled out 2 shweet pieces of rubber, to be used on the roller. Measuring 2" in diameter, I have yet to drill out the center, but cant find the rights size bit.


Finished the engine mount, and built the sliding clutch, fitted the springs. Works very well.


Closer look at the clutch, as it should engage the wheel


Closer look at the clutch. as it should disengage.


Next stop will be to fit the whole assembly to the bike. And attempt to connect the clutch cable to the slider. More updates soon!
 

VlamBallas

New Member
Jun 1, 2011
25
0
0
Johannesburg, South Africa
:-||
Put the whole drive together today, with the excption of the roller, clutch worked pretty well. 'till I realised I had the thing mounted on the wring effing side, So that'll take a good few hours to properly fix.. Swapped it around, to the right side, but that takes away most of the space needed for the roller.

So next few days will be fixing todays mess, lol.
 

NEAT TIMES

New Member
May 28, 2008
1,964
1
0
PENSACOLA, FL
Vlam

Yes the rotation is confusing, fools a lot of people. I had a buddy build a backwards bike !! Was not what he wanted. It has happened to others, your not alone.

Ron
 

Dan

Staff
May 25, 2008
12,765
115
48
59
Moosylvania
LOL, first time I made a throttle assembly, got it backwards so it started WOT and when ya gave it gas, she slowed to idle.

Did ya laugh, curse or both?
 

Dan

Staff
May 25, 2008
12,765
115
48
59
Moosylvania
Really gotta make me relive this, eh? Really was funny, even at the time. No pics but reported my self

;http://motorbicycling.com/f37/new-honda-50-a-6577-2.html#post67453


"Removed the governor. Built a really cool and elaborate throttle with great/perfect back tension. It had a pulley wheel guide. It was perfect and looked cool. I finished every thing today and carried the point beach/honda/grubee up from the celler. So dang proud of my self. Then I grabbed the pull cord and had that old fimaliure thought and feeling. "What if it won't start" Imeaditaly followed by; "what if it does" Snork.

It roared to life on the first pull. Then just went full bore. Smoke came from the gear box and the rear tire spun madly. I quickly shut it down. I turned the idle screw down and fired her back up. Same thing.....

Go look up the carb in the manual. Nuton. Look all over the carb and feel with my hands looking for some mechinisum to slow it down. Nuton.

Carol is looking on with great pity and concern and offers to hold the bike while I try to start it again. As I bend to give her a yank (the bike, not Carol) it dawned on me. I fire her up and twist the throttle. She calms right down. My Beautiful and awesome throttle assembly is bassackwards"

The cool part of mistakes like that, is ya never do it again. Well, for the most part, lol.