An idea most of you will reject... (maybe)

[6blueoval9]

Inline twin much easier.

 

[machanic]

Inline twin much easier.

I have a china girl engine apart for a little porting and bearing replacement and I think it would be fairly easy to add another engine with the clutch assembly cut off and use the small crank gear to drive the large clutch gear from the back side.

 

[mattrgray]

2 friction drive engine on both front and rear wheels would be cool

 

[Murkle]

I have a china girl engine apart for a little porting and bearing replacement and I think it would be fairly easy to add another engine with the clutch assembly cut off and use the small crank gear to drive the large clutch gear from the back side.

See! Now this I how I'd do it! Not that I will, but this is how I would if I did.

 

[Frankenstein]

I have a china girl engine apart for a little porting and bearing replacement and I think it would be fairly easy to add another engine with the clutch assembly cut off and use the small crank gear to drive the large clutch gear from the back side.

That would basically be the only way to do it with the least loss in power probably easier to keep in sync just make sure each one is behaving identical.

 

[Murkle]

Ooh, so indeed of having them fire 1,2..1,2...1,2..ect. have them fire at the same time 1 2.....1 2.....1 2..... So you get a "thumpy" engine of coarse, you might get a little imbalanced... So yeah, nevermind.....

 

[Murkle]

In advanced, I apologise for the double post. I can't edit a quote in. Easily...

2 friction drive engine on both front and rear wheels would be cool

It's been done, good idea too. A little more traction.

Here's a question. What would make more power- two 40CCs, or one 80cc?

 

[6blueoval9]

Inline 250s..weird fluttering sound

 

[butre]

Ooh, so indeed of having them fire 1,2..1,2...1,2..ect. have them fire at the same time 1 2.....1 2.....1 2..... So you get a "thumpy" engine of coarse, you might get a little imbalanced... So yeah, nevermind.....

they call that a big bang firing order. makes it easy to break traction, but also easy to regain it. lots of race bikes use such a firing order. look up big bang firing order on wikipedia for a list

 

[5-7HEAVEN]

2 friction drive engine on both front and rear wheels would be cool

I did that on my cruiser bike.

The big difference was the extra torque to climb hills and punch thru headwinds.

That, and the fact that both engines never strained themselves.
They ALWAYS shared the load

And then there was the awesome drone of twin engines.