Update on my 79cc Dyno build

CrazyDan

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Not sure about the engine bracket you have the front mount attached to can support the engine. It was made to support a gas tank, think any torque on it will cause it to break. Otherwise, very cool.
 
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MotorBikeFab

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Not sure about the engine bracket you have the front mount attached to can support the engine. It was made to support a gas tank, think any torque on it will cause it to break. Otherwise, very cool.
You may be right about the engine bracket. You are not the only one that mentioned it. It's just so convenient. But I will look for alternative options. Thanks!
 

MotorBikeFab

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79cc_1609.jpg

The pic above shows the orange oil filler plug and the unthreaded boss for another oil filler option. The thread for the oil filler plug is 3/4-10. I have some inexpensive 3/4-10 carbon steel taps coming to thread the unthreaded boss at the top of the crankcase and 3/4-10 bolts to plug what will be the drain plug. The oil "dip stick" will not work to measure the correct amount of oil...but that is a non-issue. The taps are coming on Monday and I will post pics of the finished product later next week..

The bottom plug will serve as the drain plug and the newly threaded upper one as the oil filler. The oil "dip stick" will not work to measure the correct amount of oil...but that is a non-issue. The taps are coming on Monday and I will post pics of the finished product later next week.

Also, moding the frame in the area behind the bottom bracket shell to make fitting a dual leg center stand possible...pics to come next week.
 
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MotorBikeFab

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Garden hose brass cap and threaded fitting is what most use for the filler.
Right. One has to thread the upper boss anyway... Why not use the original filler cap? And the bolt for the lower boss, now to function as a drain, is the same either way.

And it's a lighter solution. While weight is not so much an issue, those brass parts are heavy.

And the brass introduces another "trade" and look. I prefer to keep the look more or less as original to the engine as possible.
 
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MotorBikeFab

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More pics. Made a layback seat post and mounting system for a center stand. I wanted to complete the center stand and mount the pedal assembly before I finished the exhaust pipe. I am learning my welding as I go along...so it's not so great.
79cc_1716.jpg 79cc_1718.jpg 79cc_1719.jpg 79cc_1721.jpg 79cc_1728.jpg 79cc_1729.jpg 79cc_1730.jpg 79cc_1733.jpg 79cc_1735.jpg
 
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Dan

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Dig it big time MBF! Really clever, simple mount. (I think it will be better than fine, but hey)
It's perpendicular to the twist/pull of chain operation. Left forward is holding the downward and right... well, same. (I rode the short bus, wearing a helmet on the road less traveled, to the school of hard knocks)

Has a funky, bumble-bee, Transformer's look.

Did you fab the mount? I really like the way you used what was there and made it work for your purposes.

It fits and sits perfectly. Can't ask for more.
('ceptin' staying there, LoL)

Gonna be tiring with the st8 handle bars. For long riding, I personally would use cow horned ones. so I was sitting upright and not resting on my arms. Buts I be lazy, yo.
 
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MotorBikeFab

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Dig it big time MBF! Really clever, simple mount. (I think it will be better than fine, but hey)
It's perpendicular to the twist/pull of chain operation. Left forward is holding the downward and right... well, same. (I rode the short bus, wearing a helmet on the road less traveled, to the school of hard knocks)

Has a funky, bumble-bee, Transformer's look.

Did you fab the mount? I really like the way you used what was there and made it work for your purposes.

It fits and sits perfectly. Can't ask for more.
('ceptin' staying there, LoL)

Gonna be tiring with the st8 handle bars. For long riding, I personally would use cow horned ones. so I was sitting upright and not resting on my arms. Buts I be lazy, yo.
Thanks Dan! And thanks for your "bumble-bee, Transformer's look".
I did make the motor mount. I bought the downtube clamp, machined a flat and taped it 1/4-20 as the torque resist. Hope the boss on the motor holds up...time will tell.

I always seem to have a problem with the bars. I think the more comfortable bars look curiserish and I always seem to want a cafe racer or more straight bar look. And truth is that the look I seek is not a fun ride, as it's hard on the arms and wrists...Looking for a compromise that looks cool and is also comfortable.
Thanks again for your kind words.
 
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