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 Post subject: RE: NEW Cast cylinders or Top Case for the RZ500???
PostPosted: Thu Oct 27, 2005 6:30 am 
Hello Fellow Club Members and Future Club Members:<p>I've spoken to the foundry yesterday and discussed some more ideas with them. It's nice that he has a 500 engine at his shop, some friend of his dropped it off a while back to discuss this very thing with him. I'm not sure if the owner of the engine is a club member or knows of us though.<p>To make a long story short the top case idea is not a good idea, at least from his costing standpoint. However, he is more keen to revamping some of his existing cylinder line to possibly fit them onto the current case.<p>My thought now is to set it up similar to Mike C. bike done by BJ McDonald a few years back "Out in Front" section. This is four upper cylinder piston inducted intakes. Rather than messing with 4 individual carbs, have two billet intakes connecting one upper and one lower together similar to the Banshee single carb intakes. Banshee's are known for their power and even with this intake setup they are formidable. The cylinders would loose the servo actuated powervalve and use a spring loaded baffle guillotine type valve with adjustment most likely. I've got a pipe builder that can produce pipes at or near similar cost to the currect aftermarket price range as well.<p>My concern for this project stems to the fact that most members either won't work on the bike themselves, or are fearful of having others, tuners that is, build it for them. And without some simplicity to the "kit" they probably won't buy. Making this something for the overachiever do it yourself kind of guys which I've found only make up about 10% of the club anyway. So it needs to be simple within the context of the average mechanically inclined person to perform without to many additional custom pieces to have fabricated to complete the kit.<p>Any additional thoughts???<p>Regards,<br>Bill Wilson<br>Wilson Performance<br>Lee's Summit, MO<br>Member RZ500 Owners Group #573
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WVWRZ500N@aol.com


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 Post subject: Re: RE: NEW Cast cylinders or Top Case for the RZ500???
PostPosted: Thu Oct 27, 2005 8:10 am 
When I first saw the post about Ralf's work, I was<br>hoping that one of the tuners here in the States would<br>take notice.<p>My pipe dream continued with the thought that since<br>we are such a small group, it would actully require<br>all of the well known tuners/builders to participate.<br>One for cost, and two to answer the question about<br>who installs the kit.<p>I know I could handle the task of installing it, but<br>time and space to work on the bike are limited. It<br>would be reassuring to know that I could turn to one<br>(or more) of the better known tuners and not end up<br>with a crotch grenade.<p>Oh, and I love the idea of a manifold joining upper and lower cylinders. That might be worthwhile <br>regardless of new cases or cylinders.
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dan_austin@fitawi.com


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 Post subject: Re: RE: NEW Cast cylinders or Top Case for the RZ500???
PostPosted: Thu Oct 27, 2005 3:25 pm 
Bill that sounds good and you make a number of good points. I would like to have something I could install myself so I'd prefer something that didn't require machining or welding. Hopefully you can come up with something that anyone who can assemble/dissasemble the engine would be able to install it. I'm psyched!
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gpkotbh@aol.com


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 Post subject: Re: RE: NEW Cast cylinders or Top Case for the RZ500???
PostPosted: Sat Oct 29, 2005 11:09 am 
Hi Bill,<p>I appreciate your enthusiasm for re-engineering the RZ500 motor.<p>Regarding the proposal of a manifold connecting the an upper and lower cylinder to one shared carburetor, I would be somewhat concerned about the upper cylinder running lean and the lower cylinder running rich. Some of the fuel that goes into the engine is in a vapor state, and the rest in a liquid state (but in the process of evaporating). In old Detroit V-8 car engines there was always an issue with liquid fuel flow and mal-distribution. Many NASCAR engine tuners mount engines on a pivoting frame so they can see how the engine runs when there is a lot of G forces on the vehicle causing fuel to flow more to the outside cylinders. Thus I would be a bit concerned about gravity effects with your proposed manifold design. Of course I may be just overly concerned and it may work just fine.<p>I tend to agree with Dirk in Portland; that is, a CNC approach may be better than casting. In the last five years rapid prototyping technology has huge progress in capability and cost reduction. If you can make a CAD file of your design you can email it out to a supplier who will use computer aided equipment to make a lost-foam pattern, pour a casting, machine it, and FedEx it to your door in less than two weeks. It may require some investment in SolidWorks (great for CAD) or SurfCAM (great for CNC CAM), which may run you a few thousand dollars (hint: take a vacation to Thailand and you may find a vendor that is much cheaper). If you want to play around with rapid prototyping, have a look-see at www.emachineshop.com. There you can download a parametric CAD program for FREE, complete with a pricing file. The only limitation with this program is that it does not support complex designs.<p>You may also want to look on the internet for the guy in Europe that made a billet engine for his Kawasaki H2, and the guys in the U.S. that make billet cases for Banshees that will take snowmobile cylinders (scary). In essence they faced the same problem as you: how to update an old two-stroke design to modern performance levels, thus the info may be of value.<p>Best regards,<p>Tracy Hagen
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tracy_hagen@hotmail.com


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 Post subject: Re: RE: NEW Cast cylinders or Top Case for the RZ500???
PostPosted: Sat Oct 29, 2005 8:32 pm 
Tracy,<p>Great comments. In regards to the G force issue I think we can eliminate that as an issue for now, unless we get an extremely huge amount of accelleration whereby the rear cylinders will be rich and the lowers lean. :) Seriously though in using two cylinders of the same designed intake this should, I stess should, mitigate the problems we've seen with upper/lower jetting irregulatities. I for one jet the uppers richer as many tuners have for years and I think the uppers really do run better then the lowers. In reading comments made by the designers of the 500 recently they wanted to place the carbs in the V with a 50 degree V like the GP bike. And state that the crankcase reed was desired. However, it was not due to how well the bike ran but to engine life under high performance stresses since piston thrust is towards the intake side of the cylinder under power. They don't say entirely why they didn't use in the V carbs, but I speculate it was due to cost. They mention that when the RZV went up for sale in Japan that is was like 2K more Yen than the nearest 4-stroke sportbike, the FZ700 I believe. So cost was critical in their engineering factors throughout the engine and the rest of the bike. Check it out at http://21yamaha.com/mc/historic/rzv500r ... index.html. Moreover the Banshees have been using 2 into 1 intakes for years now, I've seen custom billet pieces to homemade long tube jobs that both performed great. This intake setup will neccesitate a larger single carb likely 38-44mm flat or "D" slide style. Remember these cylinders if they are new cast pieces will be "pre-ported" already top quality Nikasil plated with the high performance porting cast that way. In otherwords no further mofifications needed internally, less a bit of polishing only.<p>Believe me this is not going to be an overnight "get-er-done" approach. Anyone whose delt with me knows I think way to much and for too long sometimes making sure my first attempt is my last. Consider "Project 120HP" from 2001. This was my first attempt at porting to new specs on the 500. With 28mm flats, Toomey pipes and running pump 91 octane it makes over 106HP and 61Lbs. of torque. With the 34mm RS carbs it will make near or over 112Hp and likely 65-67Lbs of torque based on previous dyno pulls with JM pipes and the 34mm carbs. So my first attempt with this set up will be thought out very well and with your help and many others it should be my last.<p>Regards,<br>Bill Wilson<br>Wilson Performance<br>Lee's Summit, MO<br>Member RZ500 Owners Group #573
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WVWRZ500N@aol.com


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 Post subject: Re: RE: NEW Cast cylinders or Top Case for the RZ500???
PostPosted: Mon Oct 31, 2005 4:30 am 
Hi Bill,<p>Regarding my comments on fuel maldistribution, I am mostly concerned about low speed engine conditions, actually (this is the condition the engine spends most of it's time in). At low speed there is a significant amount of fuel that flow down the manifold in a liquid state, in the process of evaporating. I'm concerned that about 100% of the liquid fuel will flow into the lower cylinder, while fuel in a vapor state will flow roughly 50/50 between upper and lower cylinders.<p>Some modified Banshees, as well as some snowmobile engines, have a one-into-two manifold. In these cases the cylinders are side by side rather than up and down, thus I think liquid fuel flow will split somewhat evenly. I suppose my concern could be tested by turning a Banshee on it's side, throttle whipping it for a while, and see if it holds together....<p>Email me for my telephone number if you would like to discuss at length (I live in the Twin Cities, btw).<p>While you are scratching your head about fabricating new engine hardware, there's nothing to prevent you from considering changing the V-angle to provide more room for carbs between the cylinder. this may require more engineering work and a new balance shaft (if folks can make crankshafts and crankcases from billet, they can make balance shafts). This also means making new pipes, but that was probably a given anyway. Sone old Honda NSR250s had carbs between their V-angle so you might be able to take a cople or three sets of NSR250 carbs to make a new four carb set. Used Jap bike parts galore can be found on Yahoo's Japan auction site. Most of the stuff is over-priced junk and you will need someone in Japan to be your buyer and shipper as Japanese sellers generally refuse to do business with foreigners.<p>Best regards,<p>Tracy Hagen
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tracy_hagen@hotmail.com


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 Post subject: Re: RE: NEW Cast cylinders or Top Case for the RZ500???
PostPosted: Mon Oct 31, 2005 10:41 pm 
Why not put 2 lowers on one manifold and 2 uppers on another manifold? 2 Carbs side by side. Even have same length intake tracts if you want. If you are worried about the intake charge coming from the back of the radiator (Like on one bike in "Out in Front") move the rad to the sides. Anthony Dodd
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anthonydodd500@yahoo.com.au


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 Post subject: Re: RE: NEW Cast cylinders or Top Case for the RZ500???
PostPosted: Tue Nov 01, 2005 4:40 am 
Hi Anthony,<p>I think your suggestion would have less problems than the upper and lower into one idea. I suppose there might be some tuning issues and fuel maldistribution issues with this method also, but I think the extent of these issues would be less. Just my opinion.<p>Regards,<p>Tracy Hagen
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tracy_hagen@hotmail.com


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