Drouin........Bolt on HP?...

 

PERFORMANCE SUPERCHARGERS

The Drouin dual-purpose supercharger --- here is the hottest motorcycle product to complement your every riding pleasure. Designed specifically for docile city riding, highway touring and drag strip performance applications! All in one neat, compact and easy to bolt on package for stock or modified NORTON, HARLEY DAVIDSON & HONDA Motorcycles. We're experienced motorcylist's, too.

We give you what you expect and want in the way of the best all-round supercharger performance product. You get this including near-stock fuel economy during normal city and highway use...due to the Drouin superchargers freewheeling effect. While accelerating (any speed) the supercharger kicks in automatically every time with smooth turbine-like efficiency that must be experienced to be believed!

Yes, we have taken the hassle and expense out of super-performance for the motorcycle enthusiast at a fraction of the cost...with features that are throughout this country and the world. OVER 10 YEARS OF PRODUCT RELIABILITY!

 

Facts About Supercharging.Supercharging is the alternate to engine modification. It increases the horsepower of an engine by increasing the torque. Internal engine modifications (special camshafts, pistons, etc.) increase the horsepower by increasing the engine speed. A major factor in determining engine reliability is it's mass (reciprocating) stress which increases with the square of RPM.

A supercharged engine does not depend on higher RPM to produce more horsepower. It's air/fuel mixture is compressed and packed into each cylinder...thereby creating a more powerful and efficient charge. Mild pressure supercharging properly engineered has no adverse effect on engine dependability or reliability.

A supercharged engine is subject to less wear due to increased atomisation of fuel, also making for a smoother running and easier starting engine. The supercharged engine provides unmatchable dependability and unbeatable performance above and beyond any internal modified engine of equal displacement.  

This catalogue was dated: Printed in USA 1976 and the cost of the unit then, was $750.00 and the Distributor was H.P. INTERNATIONAL in Garden Grove California.....Can anyone match this price now? (or find one) ....doubt it!!!

But if ANYONE has more info on this...or has or had one of these units fitted...please Email me.

 
I'm very intrigued with this unit & subject.
 

 

 

Copy of the Factory Fitting Instructions (from around 1973-74)

DROUIN SUPERCHARGER INSTALLATION INSTRUCTIONS

FOR ALL 1968-1974 NORTON 750cc - 850cc MOTORCYCLES

(Combat Engine - replace camshaft with mild stock Norton version.)

CAUTION – READ CAREFULLY AND FOLLOW INSTRUCTIONS EXACTLY AS OUTLINED.

TUNE-UP-IMPORTANT: TUNE ENGINE COMPLETELY TO OWNERS MANUAL SPECIFICATIONS. 
(Maximum performance can not be achieved if this is not done.)

 

REMOVE:   REMOVE or DISCONNECT THE FOLLOWING PARTS IN THIS ORDER

1.            Seat

2.       Fuel Tank 

3.            Air Cleaner 

4.       Carburetor Manifold, Fiber.

5.            Left Foot Peg Assembly 

6.       Primary Cover

7.            Crankshaft End-nut and Washer

 

8.       Disconnect Throttle/choke Cables Spacers and Bolts, at Handlebar Controls. 

 INSTALL - INSTALL or CONNECT THE FOLLOWING PARTS IN THIS ORDER;

1.     Supercharger Primary Cover Assembly with Oil and Inspection Caps. 

2.         Left Foot Peg Assembly

3.     Carburetor Manifold, Fiber Spacers and Bolts 

4.        Throttle Cable to Handlebar Control.

5.      Drive Pulley onto Crankshaft,
do not install any washers.
 

6.         Drive Belt; adjust tension to
25-35 lbs. (high pitch tone).

7.      Fuel Tank and Fuel Lines.

8.         Seat.

 ADJUST - ADJUST DRIVE BELT BEFORE INSTALLING OUTER COVER.

Belt must be centrally aligned between flanges of supercharger pulley.

To check belt tracking momentarily, kick-over or idle engine

To Correct Alignment, Follow This Procedure;

To Move Belt Inward

 

Place 1—2 thin washers (.010” - .015” thick) behind idler mount on lower bolt.

 

To Move Belt Outwards

Place washer(s) on top bolt.

Re-adjust belt tension and double check alignment with engine running at different speeds for 5-10 minutes.

Set idle adjustment on supercharger to obtain approximately 1,000 rpm.

 

INSTALL OUTER COVER ONLY AFTER DRIVE BELT IS PROPERLY ALIGNED WHEN TENSIONED. 

Check drive belt after driving first 50 miles. Periodic checking of drive belt should be made every l000 - 2000 miles.
Belt Life: 5000 – 10,000 miles, depending on accuracy of alignment.
(Spare belts are available through authorized distributor or manufacturer at 5.00 ea.)

HIGHLY RECOMMENDED 

A manifold pressure gage to observe supercharger efficiency at a glance.

0-10 psi unit (complete with mount) available for $45.00. 

 

IMPORTANT I NFORMATION

ENGINE REDLINE — 7,000 RPM 

USE HIGH-TEST FUEL

TURN OFF FUELTAPS WHEN ENG1E IS NOT RUNNING

MAIN JET SETEING:

Richer - Raise Needle 1/16”

Leaner - Lower Needle 1/16”

 

PARTS and SERVICE
Write to manufacturer for name and address of nearest authorized service depot. 

 READERS RIDES & COMMENTS

Email from Lloyd P on his experience with the DROUIN. 

 

"I  happened across your site and noted that you wanted information on the drouin from anyone that had any experience.

I have only a little but for here is my experience.

I bought one from the factory in the '75 time frame to put on my '74 that I bought new.
 
It worked.. sort of, but mine couldn't be used easily on the street. 
 
The slide valve carb leaked a lot.  You had to turn the gas on just before you kicked it or it would flood pretty quickly.   It was best to turn the gas off and let it die of starvation to keep gas from drooling on the cases. I tried putting a Mikuni on it but never could get it sorted out. 

The main problem was that the seal on the impeller bearing sees boost pressure and it leaked, you could get one good blast up through the gears, then gas would leak through the bearing on to the flat belt.  Then the belt would slip and all boost would go away until the gas evaporated. It would work ok on a drag strip but not for the street.  I talked to Drouin but they never solved the problem that I knew of.   I spent a lot of time disassembling the bearing and looking for a suitable seal but with little success.  There used to be a guy named George Geonovich (sp?) that had a company in Garden Grove CA called HP International.  As I recall, George spent quite a bit of time trying to fix some Drouins but I don't know if he had any sucess. 
 
I ran/worked on it for a month or so then took it off so I could ride the bike normally (later I put a 900cc bore kit in). I put it away when I went back to college and forgot about it.  In 2005 I was cleaning my garage and found it in a box. I almost threw it away,  (thinking no one will know what this is) but put it on ebay and sold it to a guy in Windsor Ontario Canada. ($1700 US) as I recall.  I found the factory ID tag and some other parts about a year later, sent them to the buyer.  He wrote back that he had never mounted the blower yet. 
 
Well that is all I can recall.  Happy riding.  Lloyd"

 

I received an email from a Michael G with a couple of pics of a "project" he was involed in, so impressed with the workmanship I just had to share..Hope you dont mind Mike :)

 

"Here ya go,

We put this one together a couple of years ago at KK Speed and Sport in Erie, PA.I had a hard time finding bearings that would not self destruct as the originals did. Once I found acceptable bearings everything else was “cake”. The bike is a mover and as you can see one of the finer looking ones out there…if I say so myself."

Mike

 

 

 

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