Topic: Adapting a supercharger

[23tbucket]

 That is a sweet ride there Randakk. You guys have it nailed.....the tuning part IS THE MOST DIFFICULT !!!
The little supercharger on my bike was purchased through "japan auction" By the time I bought the "Aisen" supercharger, paid a broker, and shipping..my final cost was around $450.00 to my door. Probably spent another $450.00 on belts, pulleys, bearings and machining.  The blower came off of a fairly new wrecked Japan built car with a supercharged 600cc engine. Japan built many small cars that were never offered out of their country. This same "Aisen" company makes all kinds of transmissions and stuff...lots of "Aisen" parts on American build autos. My "Aisen" supercharger pumps 500cc per rotation...."Aisen" also makes a 300cc per rotation supercharger. I think the smaller one would have better for me.....but you know "penis envy" !!! Bigger is not better when it comes to huffing or puffing a 750cc air-cooled motorcycle engine. The turbocharger in the twinky came from 1/2 of a Mitsubishi Gallant V6.
      For what it's worth...I'll bet I have spent less money and have increased the engine performance more so with my one-off supercharger  than what most would spend on a big bore kit and camshaft?
  This blower is unlimited to boost potential. I have a backfire valve on the intake plenum.... but no boost control system. The harder the engine is working...the more boost is happening. It`s kind of interesting how this works....say you are just cruising along at 110 kpm....engine is at 5500 rpm....boost gauge shows zero......you quickly twist the throttle....boost goes up to 10 psi ...speed and rpm catch up to the throttle and zero boost again. I did bend all four of my Suzuki throttle butterflies when I was first setting things up and inadvertently hit over 20 psi boost. I keep the twinky at 7.5 psi.
If I was to do another boosted engine, I would use a centrifugal supercharger.....rather than another positive displacement. I think a centrifugal blower would be much easier to set up and tune... just one carburator or throttle body on the suction side...the centrifugal blower...a bit of a plenum...and the intake boots.

[Gearheadgreg]

My Eaton M45 lung has a ribbed groove belt drive No pop off valve, if it burbs it will squeak the belt, But it does have a bypass valve that helps it be very street able, 8lbs boost, @ 65 Mph cruising down the road i have 15lbs Vacuum, or at any Hwy speed until i throttle aggressive it boost instantly, I run a very aggressive Initial lead on my advance curve that will instantly back off 8* @ 1.5 Lb of manifold pressure, result ? 35 MPG, well......i have friends that have seen as low as 17mpg dyno     

[23tbucket]

Gearheadgreg:  I have heard similar stories of folks putting superchargers on their vehicles and getting more miles/kilometers per gallon/liter than before....must have something to do with efficiency?

Using ribbed belts is a very good idea...I went with toothed timing belts and pulleys to prevent slippage on the small OD of the external alternator and I thought I wouldn't have to run the timing belts all that tight and ease some of the load on the jack shaft and bearings.....wrong!!! These timing belts have to be good and snug or they will start whipping, vibrating, and will eventually tear themselves apart....lesson learned!!!
   Ribbed belts is the way to go if anyone is thinking of doing something similar.

Sweet dyno video...in my neck we are limited to the 'redneck" dyno....lol

[Randakk]

SNIP

Using ribbed belts is a very good idea...I went with toothed timing belts and pulleys to prevent slippage on the small OD of the external alternator and I thought I wouldn't have to run the timing belts all that tight and ease some of the load on the jack shaft and bearings.....wrong!!! These timing belts have to be good and snug or they will start whipping, vibrating, and will eventually tear themselves apart....lesson learned!!!
   Ribbed belts is the way to go if anyone is thinking of doing something similar.
SNIP

Agreed 100%.

We have used modern serpentine drive belts on all our blower projects with very good results.  Gates makes a line of blue Racing belts that are ideal for blower duty. Serpentine belts wear a very long time and have incredible "grip" without having to dial in unnecessarily high belt tension.

Best of all - compared to a direct-drive cogged belt, a serpentine belt greatly reduces the risk of "backfire" damage and simplifies the design of the "anti-backfire" valve on the plenum. Some folks leave out this design element altogether (not me).

The anti-backfire valve on these set-ups are often mistaken to be "pop-off" valve. They are not. Basically they just ride and are there for insurance.

Backfires can mean instant death to complex (and expensive!) fabricated plenums. But the good news is that under the extreme stress of a backfire, a serpentine belt will "slip" just enough to allow the blower to momentarily rotate back-wards to relieve the pressure of a back-fire.

Back-firing is not really an issue once the carb jetting is dialed in. This is why blower setups must start out very rich on initial start-up. Ditto for eliminating all vacuum leaks!

It takes some creativity to get the belt you need (in the available lengths) to mate up to the drive ratio you select (with pulleys fabricated or purchased) to fit into the available real estate.

[Gearheadgreg]

Belts!! like you guys i have tried them all..LOL! (Goodyear Gator) and a few others, The best so far has always been "Gates Green Stripe" Randakk i have not seen that Blue line Gates Belt?...where did you find that? i have a hell of a time even getting a Green stripe Gates up here. TIA

[Gearheadgreg]

Gearheadgreg:  I have heard similar stories of folks putting superchargers on their vehicles and getting more miles/kilometers per gallon/liter than before....must have something to do with efficiency?

Using ribbed belts is a very good idea...I went with toothed timing belts and pulleys to prevent slippage on the small OD of the external alternator and I thought I wouldn't have to run the timing belts all that tight and ease some of the load on the jack shaft and bearings.....wrong!!! These timing belts have to be good and snug or they will start whipping, vibrating, and will eventually tear themselves apart....lesson learned!!!
   Ribbed belts is the way to go if anyone is thinking of doing something similar.

Sweet dyno video...in my neck we are limited to the 'redneck" dyno....lol

A lot of guys buy Valkyries and then #$%* about gas millage ? WTF it has 6 28mm carbs LOL!! but the stock bike will get about mid thirties MPG, not that good for a MC, 145 hp, 128 tq.......listen to the end of each pull you can hear the belt slipping on that Dyno pull. i have not put her back on the Dyno with the belt tight. But like yourself i use that Redneck Dyno myself LOL!!  that there is good stuff!!!

[Randakk]

Belts!! like you guys i have tried them all..LOL! (Goodyear Gator) and a few others, The best so far has always been "Gates Green Stripe" Randakk i have not seen that Blue line Gates Belt?...where did you find that? i have a hell of a time even getting a Green stripe Gates up here. TIA

I live in NASCAR land (where most of the teams are based).  Go to any race car fabrication shop and sweet talk the head engineer to let you make a copy of the salient pages from his Gates Belt tech literature.  Armed with the right part numbers, you can buy the blue racing belts online from sources like Summit, Pegasus Racing and others.

[Gearheadgreg]

Belts!! like you guys i have tried them all..LOL! (Goodyear Gator) and a few others, The best so far has always been "Gates Green Stripe" Randakk i have not seen that Blue line Gates Belt?...where did you find that? i have a hell of a time even getting a Green stripe Gates up here. TIA

I live in NASCAR land (where most of the teams are based).  Go to any race car fabrication shop and sweet talk the head engineer to let you make a copy of the salient pages from his Gates Belt tech literature.  Armed with the right part numbers, you can buy the blue racing belts online from sources like Summit, Pegasus Racing and others.

Thanks, i will call Summit, looking at your Avatar? with the Downdrafts on it, got any pics of that bike?

[Randakk]

SNIP   looking at your Avatar? with the Downdrafts on it, got any pics of that bike?

Yep.  Plenty of details on that here:

http://www.randakks.com/Dual%20Weber%2040%20IDF%20Conversion%20for%20Honda%20GL1000.htm

[Gearheadgreg]

Great info Randakk, the reason i asked is my neighbor is pulling his heads off his Valk this winter, and we have access to use a friends machine shop to fab intake runners for Porsche Weber downdrafts, They are 30mm and we have 6 28mm carbs on it now, we are sending the heads off for Porting and it already has performance cams in it with racing exhaust, please feel free of some thoughts of this or any recommendations, He does not want a blower. here is what we are looking at> http://www.specialtycarsservicecenter.com/used911parts_folder/used911parts.htm 

[Randakk]

Great info Randakk, the reason i asked is my neighbor is pulling his heads off his Valk this winter, and we have access to use a friends machine shop to fab intake runners for Porsche Weber downdrafts, They are 30mm and we have 6 28mm carbs on it now, we are sending the heads off for Porting and it already has performance cams in it with racing exhaust, please feel free of some thoughts of this or any recommendations, He does not want a blower. here is what we are looking at> http://www.specialtycarsservicecenter.com/used911parts_folder/used911parts.htm 

That should work fine, but the "devil is in the details."

30mm venturis are probably borderline oversize unless you are tuning for max performance at high rpms.

The good thing about Webers though is that they can be can be tuned to run on anything...depending on the expertise of the tuner of course.

I've considered that exact setup if I ever do a hot rod Valk.  It would certainly look and sound awesome!

[Gearheadgreg]

Well went for a last ride last weekend, my neighbor came along with me on his cammer Valk, 23tbucket he did 3 Redneck Dyno pulls!!! LOL!! any way i was getting rubber in all 3 gears trying to feather the throttle.Valkyrie

[RRRToolSolutions]

No helmet.....

[Old Scrambler]

Oldfelt asked and the sohc world delivered.....................BTW, Oldfelt.........do you know Fast Frank from Ray, MN? 

[Gearheadgreg]

No helmet.....

No helmet? Gearheadgreg always wears his helmet, Wildbill is 65 years old and on Oxygen most of his day,,,....He lives Hard and Rides hard,,That side car is built for his Son who had his Helmet on 21 years ago and was a National BMX champion, went over the handlebars and is a Quadriplegic.....Not gonna get into a OIL thread regarding Helmet Laws and one's rights......I Use Honda blend 20-50 with no Moly. Here is our riding group this should pi$$ at least one person off LOL!!.....OH? Wildbill fimed this at over 80 MPH  Starboy slowed on the back tire in a turn at the freeway off ramp to a complete stop. LOL!! well? he has his helmet on LOL!!  starboy if you have seen any Indian commercials on TV Wildbill was hired to do the rolling work. http://www.motorcyclecameradolly.com/

[Randakk]

My supercharged Honda CBX was mentioned above.  It is finally finished ...after a 3 year build. It turned out very nice.
 
It will be unveiled at a Bike Show in Spencer , NC on May 12th.
 
Details here: http://www.randakks.com/Randakk's%20Customer%20Appreciation%20Rally.htm
 
Here's one sneak preview:
 
 
 
Commitments to some editor-types limit my ability to share many more details until after the bike show on May 12th.

[cgswss]

We built a Suzi 1100 with a supercharger (drag bike)  We built the whole engine around having a supercharger which meant lower compression pistons and a special cam grind.  Of course we used a bit more then the 10lbs of boost I have seen on street bike conversions.  We used Webers and ran on alcohol.  (2 valve Suzi- not the 4 valver)  Being a drag bike, the frame was purpose build so there was no problem with where to mount the supercharger.  We spent most of a whole season trying to get it all sorted.  One of our biggest problems was ignition.  As soon as we got up on the boost we would start getting spark shorting out.  We cobbled up an ignition with 4 coils (and real BIG wires)  I wish I could tell you how successful it was, but I can't.  I think I only made it to the finals 2 times and had something go wrong each time.

Near the end of the season we trucked out to Pomona and on my second comp run I grenaded the engine at about 170 There wasn't enough left of it to make it worth hauling back to Michigan so we sold it to another racer for $500... and we got the good side of that deal (BMFG).  I'm glad I had my AA mod bike or I would have gone all season with no win.

I also had a Kowa 750 turbo bike.  It felt like a 500 until the revs came up, then a high revving 1000.  I only kept it for about 6 weeks and went back to an 1100 Suzi.  Guy that bought it from me tried to make it into a drag bike, But I killed him everytime we ran up against each other in practice. (my mod class 1100)  If I remember right he never got the bike even close to the 10s and frankly it was not near as much fun to drive on the street as 1000/1100.

[Gearheadgreg]

Looking forward to seeing the CBX, i see this fella riding this up here in New England all the time,,he has Zoomy drag pipes with vacuum actuated butterflies for controlled back pressure, sounds amazing!!

[Randakk]

The "New England" supercharged CBX pictured above has some interesting details. We did not become aware of that particular bike until ours was nearly completed.

The 2 bikes have very different design approaches, engineering and execution.  They are more probably more different than similar I think....other than both having 6 cylinders and a blower 

For example, to preserve cornering clearance on an already very wide bike, we chose a different spot other than the end of the crankshaft as the PTO to drive the blower.  That single decision drove lots of other details.

I like them both!

[Gearheadgreg]

Bill Bushings "owner" Magnacharger GL 1520 Valk motor, 210 HP, good friend of mine did the design with Bill for this setup.    

[cben750f0]

i always love this vid...lol
http://www.youtube.com/embed/mrxC68yiITg

peace

[luhojs]

This is waiting to be put on a SOHC 750 engine...
..hoping my image insert comes through..



Anyhoo, it's a shorrock supercharger of UK origin.
Details in this link:

http://www.thefang.co.uk/shorrocks.htm

Since it's 750 cc swept volume per rotation i've got an idea about the drive ratio...I also got the manual and the special tools in the deal. Oh and BTW this is the never used reserve blower and the price was in the 2 figure range.

Bummer is that this build is number four in the current standings.
I need to quit work or hire a mechanic