NRG 140cc twin engine in progress.

Yes, that's pretty much how I saw it in my head - a keyed shaft on each side with a supporting sleeve. It needs a more heavily engineered solution than a splined shaft, as splines might be Ok for final drives through sprockets, but that's after gearing down and power losses through the transmission.

 

The links are not the same machine - the first two are of a complete construction.
The last lot are of a lambretta - which has a twin crank stock. But it does show you that two pipes are required. If This guy used two - you may be sure there is a good reason - because if there was a better way of doing it - he would build it. Look what he did to a pair of sport pro's for the 'Bretta !

 

View attachment 8423 Just a little update on the twin, the second pick-up now mounted/timed and built up. Waiting on reed blocks n manifolds then I'll make a inlet manifold to run a single carb to start with. 80cc starter motor. Getting there slowly!

 

Nice project, enjoyed reading this

 

A little update for those that are interested in my slow moving project! I might actually get it running soon!

 

That's nuts ! I love it.

 

+1
Will engine be for sale too in the future?

 

nobody will want to pay what it cost to build!

 

This is fantastic!

only thing that makes me sad is the 17.5 carbs but what you have 2 i cant see it slowing you down too much, if anything will just make it more usable

 

Loving it! - we helped buil an op-tronic ignition for a a guy who built a KH250 (IIRC) based 7 cyl stroker back in the late 90's lots of fun to be had eh.

You considered doing a faux 'V' twin config wrt crank and ignition firing angles? Suposed to be a really torque-ey set-up and smoother/less vibration than a 180 degree twin...

Cheers bud nice bloody work indeed

Shaun.

 

That wouldn't be Allen Millyard, would it? I remember the first 4-cylinder Kawasaki he did, called "A Little Bit On The Side". he's a legend for what he can do with Kawasakis.

Simon Whitlock also built a few epic Kawasaki bikes.

 

Most likely him, name rings a loud bell but no sure - it was over a decade and a half ago and I used to drink heavily heheheh...

Not sure if he ever got the 7 cyl. working but we also worked with him on a 5 cyl - crazy tings eh ',;~}~

 

You considered doing a faux 'V' twin config wrt crank and ignition firing angles? Suposed to be a really torque-ey set-up and smoother/less vibration than a 180 degree twin...

Cheers bud nice bloody work indeed

Shaun.[/quote]

It wouldn't be easy making a V twin as it would need a balance shaft !

 

It wouldn't be easy making a V twin as it would need a balance shaft ![/quote]

Fair point mate it'd def. need some careful balancing but the Yamaha XS parallel/180 deg. twin crowd seem to have had some tricks up their sleeves from what I recall 'back in the day' - was only my curiosity getting the better of me anyhow.

',;~}~

Cheers!

Shaun.

 

I'm not a good enough engineer to make a V twin.

 

Hey bud you're doing fantastic with this 180 twin - I couldn't do it! I think maybe if you just had the tools ',;~}~

Shaun

 

Update Video of 140cc Twin so far....

 

Pancake filters

 

nice, the way the exhausts are reminds me a bit of the tz750, with exhausts pointing out where ever there was room! have you ridden it yet? how does the balance feel with the cylinder being offset from the wheel like that? i guess its not really noticable

 

I'll re-make the pipes so they are stacked like a formula 125 but just using as is while I'm testing the engine. If it all goes tit shaped again I can just sell the pipes as they'll bolt straight on a std scoot. As for the weight it's no problem, my old 250 twin was heavy and also moved over to the left of the frame but I had to use a wheel spacer, this engine sit's in the original position, you'd hardly feel any difference riding it.