Drouin Supercharger - Commando handling (2013)

This has been kicked around in my head for some time but I've never heard from other past or present users of a Drouin supercharger on a Commando.

I ran an older two belt version of the Drouin on my Commando Mk2a back in the 70's and distinctively remember it causing the bike to feel sluggish when turning in. In essence, I felt the Drouin took the nimble feeling out of the Commando.


Though the turbine has little mass at rest it has considerable inertial (gyroscopic) mass as it it turning at 7 times the crankshaft speed. These forces grow by the square of the velocity. My hunch is that this gyroscope high, behind and left of center of the bike may have been the source of the problem.

As a sanity check, has any other user of a Drouin Supercharger on a Commando experienced this?

Dances with Shrapnel said:

This has been kicked around in my head for some time but I've never heard from other past or present users of a Drouin supercharger on a Commando.

I ran an older two belt version of the Drouin on my Commando Mk2a back in the 70's and distinctively remember it causing the bike to feel sluggish when turning in. In essence, I felt the Drouin took the nimble feeling out of the Commando.


Though the turbine has little mass at rest it has considerable inertial (gyroscopic) mass as it it turning at 7 times the crankshaft speed. These forces grow by the square of the velocity. My hunch is that this gyroscope high, behind and left of center of the bike may have been the source of the problem.

As a sanity check, has any other user of a Drouin Supercharger on a Commando experienced this?

Click to expand...

Because Drouin owners are sane... :roll:

swooshdave said:

Dances with Shrapnel said:

This has been kicked around in my head for some time but I've never heard from other past or present users of a Drouin supercharger on a Commando.

I ran an older two belt version of the Drouin on my Commando Mk2a back in the 70's and distinctively remember it causing the bike to feel sluggish when turning in. In essence, I felt the Drouin took the nimble feeling out of the Commando.


Though the turbine has little mass at rest it has considerable inertial (gyroscopic) mass as it it turning at 7 times the crankshaft speed. These forces grow by the square of the velocity. My hunch is that this gyroscope high, behind and left of center of the bike may have been the source of the problem.

As a sanity check, has any other user of a Drouin Supercharger on a Commando experienced this?

Click to expand...

Because Drouin owners are same... :roll:

Click to expand...

Gee, thanks but a major distinction here is there are owners and then there are those that use :lol: Please don't make that mistake again.

So anyone with direct "relevant" experience out there that is willing to share?

Hobot weighs in: Counting down 3.....2.....1.....

Well, actually this inquiry is in support of hobot's endeavors as he has asked about this some time ago and in a recent PM he asked again (which is ok).

So no, this is not baiting although it would have been a perfect platform. :lol:

Just want to see if there's any consensus on Drouin superchargers (on Norton Commandos) and the superchargers impact on their handling.

So everyone else just bugger off

Bruce MacGregor with identical twin of Peel's Drouin said once he got it in the Carolina Smoky Mt's twisties a couple years ago instead of his bee line home base, he distinctly noticed it resisting leans so didn't explore that very much. To me the modern balloon tire beasts are a hassle to tip over or pick back up in time, so to over come that bothersome work load I just trip the SOB's down with power fast as a crash. [read my punch line sign off] One of my big hopes for the Drouin is to make Peel trip out in 4th to save the poor sleeve bushes turning to dry ceramic grinding paste. I've read up on this gyroscopic business and how to cancel by another gryoscope to find there ain't a quantum computer yet to figure out all the factors to predict when > gyro's ain't on same shaft or same level vertically or horizontally. The ones used in stablization in boat are gimbled to sensors to motors to fins not its mass resisting hull motion and rotation aim in satellites is done by changing speed of one or more gyro up or down. I have expert instructors signed proof I don't ride cycles like any one else and after Peel which don't handle like nothing else, I think the impeller may be a benefit to her flight envelopes as one of Peel most magic acts was not changing lean angle on drifts or leaps, only pilot iput changed lean angle once set it just stayed there, so no athletics no surprises, to such ease and security road racing was boring but for the blind surprises, so real mystery to me is how THE Gravel and Woods handle the blower. Flywheel inertial is another subject.

Hi,
I don't know about the Smokie Mountains as I ride mostly in New England.

But, I do notice a resistance from the bike to want to lay over when initiating a turn by counter steering thru a twisty especially above 4000 RPM.
It wants a little more push on the handle bar to lay over.

Not enough to cause a problem. But i can feel a difference between running the Drouin verses carbs.

I used to ride my Norton from Rangely Lake in Maine to Lake Placid NY, back roads twisties with some friends who rode modern bikes.
It was much easier on ME with out the Drouin.
We still do this ride or similar every year, But now I do it on my Ducati.

Bruce MacGregor

Thanks Bruce. This was what I was looking for. Any other Drouin users on the forum interested in chiming in here?

Almost sounds like Drouin support group.

YES, still alive (and Kickin`)
https://photobucket.com/gallery/use...m91aW4tYnJlbWVuMjAxNC9QODE1MDA3NC5qcGc=/?ref=

Nice!

Any comments on how it affected the feel of the bikes handling?

Supercharger and standard drum brakes?

Wow!

Fast Eddie said:

Supercharger and standard drum brakes?

Wow!

Click to expand...

Yup, and He's still alive and Kickin.
I say good for him......