Superchargers

[shane007]

Hey guys, this site has been a lot of help to me in getting my bike running. When I first got it running right the power scared me. But now I want more... So my question is are there any supercharged xs11's out there?
I've read about some turbo builds and I have a few ideas but have never played with any form of forced induction. I will post later with some of my ideas. Any suggestions would be great. Thanks, Shane

[natemoen]

Never seen one here.

What were you planning for it? We're you going to use the stock carbs? A single carb? Something else? How would you power the supercharger?

I have heard of a handful of supercharged xjr1300s, concept for that may work for the xs.

[shane007]

I haven't picked out any one supercharger yet, but I'm leaning towards blow through on all 4 carbs with an used Eaton. Maybe an m90. I know I have to pressurize the fuel and was thinking of running a pitot tube from the pressurized manifold into the fuel tank.
I'd like to run the supercharger off the timing plate but I don't know how strong that plate is.
I'm thinking of about 5-7 pounds of boost. The reason I chose supercharger over a turbo is for the instantaneous boost. It's always there and doesn't have to spool up and won't scare you when it suddenly comes on.
I have nothing figured out for the vacuum advance though.
Thanks Nate, I will look into how the xjr's are doing it.
...almost forgot but the problems I see with a draw through would be slow throttle response, if you have a backfire it'd be goodbye supercharger.. And probably carb. Also I think options would be more limited although setup and tuning would be much easier with a draw through.

[3Phase]

Shane,

Here's a supercharged nitro XS1100 that might give you a few ideas:-


xs1100.com.au: NITROUS XS1100


.

[TopCatGr58]

Scott,

Supercharged AND Nitrous??

Hey Shane, have we told you about the guy that had his turboed IIRC for 1/4 mile racing, and kept bending driveshafts!?!

You're also loosing about 10% of the power from the engine to the rear wheel via the middle drive/driveshaft and final drive assemblies. Folks wanting a bit more power have gone the Chain Drive conversion route, a bit simpler and possibly a lot cheaper than a TURBO or Supercharger!!

And, John England had NO2'd his machine, I would think that would be about the cheapest easiest way to get some boost...and I think his was a WET system, pushing both NO2 and fuel thru the Synch Ports in the intake boots!?

I've also got a few photos I harvested a years ago, I'll see if I have them on photobucket, and if not, will put them on there and post here!

T.C.

[shane007]

I remember reading that thread on the Aus. Forum. Looks much simpler than the way I was thinking as his is draw through. Definitely tempting to try if I can find a draw through supercharger.
Also I heard about that guy twisting driveshafts but I think there's other people with more power than I could put down. And I kind of like having the driveshaft lol. Maybe I just have tunnel vision right now ha-ha.
I am also looking into N2O but would rather be blown.
I'm going to start looking into a draw through setup that I can swap back to stock if it doesn't work like I hope. Thanks for helping bounce ideas around!

[Rasputin]

Somewhere on this site is a blower shown. I do believe it was in the for sale portion. It was mounted on the left side from the timing cover area and used a belt to drive it. I can not find it yet in my searches, but mayhaps someone remembers it. I also believe that member Math did up a bike but that is a foggy memory so it may not be correct.

[3Phase]

Yeah, that's what I said when I saw it!

That's one XS11 where the rear wheel bead locks are mandatory so it can safely spin the rear wheel and melt right into the ground underneath you as you let out the clutch!

.

[shane007]

Alright guys, I have decided on an eaton m45 out of a Mercedes SLK. I would like to put the carbs in one large plenum but I don't think I have the skills to do that. I may be able to just run piping right to each carb inlet from charger. Still trying to figure out what to do with ignition timing and how to boost reference the fuel supply.
I just want to do this project to learn and expand my skills. I'm going to make everything as reversible as possible in case I can't make it work right. I'll update yall once my supercharger comes in.

[TopCatGr58]

Hey Shane,

I haven't gotten to check my photos yet, but some more info regarding the vac. adv. unit and it's function. Yes, it is an "Advance" unit, but really only comes into play during CRUISE status....low throttle input and load on engine, so that the throttle plates are fairly closed and the fuel is a bit leaner, and so the vac. advance kicks in to increase the timing up to a max of total 52 degrees to take advantage of the lower fuel levels to increase fuel economy. Upon cracking the throttle open, the amount of vac. signal to the advance unit "Decreases" and releases to allow the timing to return to the less advanced position around 35 degrees which is the maximum amount of advance for the maximum amount of POWER at the ~5K+ rpm range.

Some members have run their bikes without the Vac. Advance attached, and have still have plenty of power....they have just lost a little bit of the fuel economy provided by the extreme amount of adv. at cruise rpm/load.

As to the ignition....you might want to look up other electronic ignition devices....can't recall what they are called, but look up Fuel Injected, and you'll find the threads about it.

T.C.

[Eveready1100]

Shane,
you do realise that you won't be able to use the stock carbs with a blow through system as they rely on vacuum from the motor side to make the things work. Even a change of filter types can create tuning issues, let alone having a blower forcing air into them from the outside.

[TopCatGr58]

Photos

Hey again,

Okay, here are the photos I promised.

This first on is an official Yamaha Funny bike, remember, you can click on the photos to view the larger original file.



These next ones are of the Supercharged bike. The ALT cover is a DRY cover, and the Field Coil has space in the middle to allow it being drilled thru to allow a shaft thru it and still retain functionality, just would require a longer bolt to hold both the outer pulley as well as the inner ALT rotor!











And here a few shots of the guy with the TURBO at the track!







T.C.

[Mathh]

I'm curious what you want to do with the bike. I chose for the turbo instead of the supercharger and have never had any regrets. Although I hardly ride it anymore the engine has seen more than 200.000 turbocharged kilometers (125.000 miles) riding fast through Europe. Most of its life the engine proved to be bulletproof. In my early days (1982) I took it to a tuner in Holland (Jan Smit from JSPP who was heavily involved in dragracing). The engine of my XS already had 60.000 kilometers on it and I had told him of my tours through Europe. I already had swapped pistons five times because they tended to melt everytime I looked for more horsepower. More horsepower was easy hahaha, just turn in the bolt on the wastegate to create it. After I asked him everything I wanted to know about superchargers Jan Smit told me I already made the right choice with the turbocharger. When I asked why, he said I could never had done that mileage in such a short time with a supercharger, especially when riding it hard, as I did. Normal things like powershifting and especially hard downshifts are a nono on a beltdrive supercharged street bike. Imagine when downshifting hard your crankshaft tends to slow down enormously, even stopping sometimes and imagine the effect that has on the drive belt. It can snap of course and will by the force created by the stopping crank trying to slow down the supercharger.. As for Nitrous ..... there was a period I had added that as well and the only thing I will almost remember is that it was VERY expensive charging that bottle several times a day....

[shane007]

Eveready1100: I believe that if you show all those little air ports the same same pressure the tuning should not change much as long as fuel is not blown back out of the bowl. One of those ports on the carbs goes right into the slide diaphragm chamber. I think the issue with the pods was blockage of these ports causing a pressure differential of that chamber relative to the amount of vacuum in the carb itself.
Many of the turbo Hardley guys all run keihin cv40's which are very similar to our carbs. I understand there will be tuning issues but hopefully I will be able to make everything work.


Topcat: thanks for those pics! I have never seen either bike before. I never knew that cover was a dry cover lol. That seems like a much better idea than the timing plate. Does that bolt just screw right into the crank? I'm wondering how well that bolt would cope with the stresses of a charger. Bet its stronger than the timing plate though

Nate: The bike is mostly pleasure riding. I dont powershift or anything. Always using clutch lol. Really just looking for a wide strong powerband and want to be scared in a straight line again. Just crack the throttle at any rpm and the boost is there. As I understand it I would be a bit more prone to detonation however being that a supercharger usually has higher output temps than a turbo I guess I just want to try to build something different.
One of my concerns is the stresses placed on the crank from the charger. I completely forgot about accounting for the kinetic energy of the rotating blades though lol. What would be awesome is if I could have some kind of clutch system on one of the pulleys.


All that aside... I am getting together the rest of the parts for the fuel and air system. My welder buddy can help me setup a pulley system and manifolds. So far I have gotten a 9 psi electric and a boost referenced rising fuel pressure regulator along with a drive pulley.
Still needed is a way to let boost bypass my carbs at closed throttle and a relief valve in case of over boosting. Let me know if anyone has any ideas. Thanks, Shane. Pictures will come once I start getting parts in!

[TopCatGr58]

Hey Shane,

When I did my Alternative Alternator Mod, I put a pulley on the ALT rotor, and replaced the bolt with a longer one. I left the rotor/flywheel in place and used it as the base for a plate that I then mounted the pulley into/onto, which from what I was told would take the stresses off of the bolt and put it onto the rotor...which is well secured onto the crank with a cone shaped fitting/interference fit.

See this thread of that mod....it's a bit long, the photos are about 1/2 way into it! http://www.xs11.com/forum/showthread...or+alternative

IF you are going to be keeping the OEM ALT function, then you won't be able to put a plate on the end of the rotor....so you'll need to have a fairly wide base of the pulley to be able to mesh with the rotor and crankshaft end as to minimize the amount of stress on the bolt from the tension of the belt and pulley on there!

T.C.