Jump to content

Supercharged Banshee?


Paulie B

Recommended Posts

There are SOME people out there who think that a blower on a bike is the cats ass... Now lets all remember that I know nothing. The first (of many) major issues is that there is no "pulse" with a blower it is constantly pushing air, thusly you get none of the pulse action that the 2 stroke exhaust creates.. With that being said, there is a company that is super charging LATE MODEL 2 stroke snowmobiles that are both fuel injected, and have power valves. The kit is limited to 5psi, and as I understand it they are manipulating the timing of the PVs to help keep some pressure in the cylds rather than it simply just blowing right through. The idea that the blowers use too much HP to turn is pretty far out there these days with the technology of the pro-charger and the roterx blowers. Although they do infact take SOME power its rather minimal. Theres a whole host of other issues that come into play with the blower stuff, from the weight, to the belt systems, the gyro affect, and many others. Coming from a guy that has owned, ran, tuned, delt with 2 stroke boosted stuff I would RUN the other way from this crap. If you want boost, use a turbo. JMO and I know nothing.

Link to comment
Share on other sites

  • Replies 34
  • Created
  • Last Reply

Top Posters In This Topic

To be clear I know even less lol. I'm just wondering why this isn't done more often especially the guys who do 300ft drags with $$$$ to spend.

I do know the thermactor air pumps are good to 5 psi.

A real controllable powervalve is genious! I suppose it would have to be electronic to work right for this.

Link to comment
Share on other sites

The problem with supercharger on a 2 stroke is the fuel charge gets blown out the exhaust. With a turbo it creates its own back pressure to keep the charge in the cylinders.

 

I think you need to learn more on how a two stroke works. Also how an expansion chamber works. This happens regardless of what type of compressor, even happens without a compressor or a pipe.

 

@ n2o, how many psi will stock seals hold back? And do you use different seals for your applications?

Link to comment
Share on other sites

I understand how 2 strokes work and pipes i was into snowmobiles for years had a turbo sled. So like all motor heads I want more like a supercharger no turbo lag. When I did research into superchargers on 2 strokes the problem was getting the pipe to work with the charger. To get good power you need 12 to 20 psi think of the nightmare tuning that pipe and jetting. Here is a link http://www.snowmobileforum.com/engine-drivetrain/67972-supercharged-2-stroke-sleds.html From what I got out of it is they have a valve on the stinger.

Link to comment
Share on other sites

Ok long version lets say you got the supercharger on the bike working carburetor is mounted to the supercharger (So supercharger is sucking through the carburetor) The carburetor is now a valve for the supercharger closed its under vacuum trying to make boost at idle. (Note gas is being compressed and heated bye the supercharger). Getting it to idle wont be a problem but at 3000 RPM and you open the carburetor up you have 10Lbs of boost or more now your 350 cc is like a 700 cc engine a normal pipe is not up to this task. The 10Lbs of boost in the crank case gets amplified when the piston compresses it more. So now the pipe will need a sonic wave in the chamber strong enough to stuff gas back in cylinder. Now it revs to 10,000 rpm and 15lbs boost. I hope your jetting and pipe are in good tune she may melt down at this point. When off boost its going to be a dog because the engine is a 350 cc again and the pipe is tuned for boost or 700cc I don't see how a normal expansion chamber and stinger can handle all the low to high boost with out some kind of valve on the stinger to change the back pressure in the expansion chamber. Turbos make there own back pressure when it spools more boost more back pressure in the pipe. That's my $.02 hope this helps some one.

Link to comment
Share on other sites

There are SOME people out there who think that a blower on a bike is the cats ass... Now lets all remember that I know nothing. The first (of many) major issues is that there is no "pulse" with a blower it is constantly pushing air, thusly you get none of the pulse action that the 2 stroke exhaust creates.. With that being said, there is a company that is super charging LATE MODEL 2 stroke snowmobiles that are both fuel injected, and have power valves. The kit is limited to 5psi, and as I understand it they are manipulating the timing of the PVs to help keep some pressure in the cylds rather than it simply just blowing right through. The idea that the blowers use too much HP to turn is pretty far out there these days with the technology of the pro-charger and the roterx blowers. Although they do infact take SOME power its rather minimal. Theres a whole host of other issues that come into play with the blower stuff, from the weight, to the belt systems, the gyro affect, and many others. Coming from a guy that has owned, ran, tuned, delt with 2 stroke boosted stuff I would RUN the other way from this crap. If you want boost, use a turbo. JMO and I know nothing.

 

Can you elaborate on the gyro effect with a sc?

 

Sent from my DROID RAZR using Tapatalk 2

 

 

Link to comment
Share on other sites

I think you need to learn more on how a two stroke works. Also how an expansion chamber works. This happens regardless of what type of compressor, even happens without a compressor or a pipe.

 

@ n2o, how many psi will stock seals hold back? And do you use different seals for your applications?

 

My turbo bike would spike around 18 at the hit of the nitrous and sustain the 12 pound range down track and I had zero issue with seals. Jordys is spiking a bit higher and sustaining a bit more down track and hes had some crank seal issues. There are remedies for the seal issue that Jordy will be implementing for next year that will solve the seal problems. 

 

Can you elaborate on the gyro effect with a sc? Sent from my DROID RAZR using Tapatalk 2

 

Just like when you were a kid with a bicycle wheel in your hand and you spun it, it would "gyro" (I think this is the proper term) as you moved it back and fourth it was harder  to turn and the wheel the faster you spun it. The same principal applied to the blower, and as you know because you own one they are over driven to crazy RPM inside the case so the blower acts just like your bike wheel did when it was in your hand. In say a sled the affect is somewhat less noticed because of the size/weight of the sled (but it sill affects it) but say on a banshee with a blower that turning a trillion RPMs strapped to a machine that weighs 300 pounds the noticed affect is going to be much more. 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

×
×
  • Create New...