Page 1 of 2 1 2 LastLast
Results 1 to 10 of 11
  1. #1
    Mark22's Avatar
    Join Date
    Sep 2009
    Location
    Springfield, MO
    Posts
    191

    Designing a new Rotary Valve

    I need an oppinion from the hard-core racers and builders out there... If you could make a 787 rotary valve different (just the valve), what would you do different?

    I recently bought a `97 XP with a trashed crank and cracked block. It had metal shavings all over in the front cylinder and even into the rotary valve and intake manifold. The manifold is scored good, but nothing a good mill can't take care of. The valve itself is scratched and scored good too.

    I have a unique piece of machinery at my college that I am free to use. It is called a wire EDM. For those who are not familar with EDMs, it is basically a CNC hot wire cutter for metal. Similar to a waterjet, but far, far more accurate. It's way slower though... but it loves steel!

    I have become fairly proficient with the EDM and think I might be able to cut a new rotary valve. If anyone has blueprints of one, that would be awesome! Let me know what you all think...


  2. #2
    dghal's Avatar
    Join Date
    Jul 2008
    Location
    League City Texas
    Posts
    280
    The key being you would need blueprints,,

    I just use the Carbon Tech Rotary

  3. #3
    Mark22's Avatar
    Join Date
    Sep 2009
    Location
    Springfield, MO
    Posts
    191
    I don't NEED blueprints, but it would save me a ton of time. Cutting the right splines are the only thing that is gonna trip me up. Finding the right standard for the splines is going to be tricky. If Seadoos were made in America, it would be easy, just use SAE standards. I have no idea what to use for the metric standard.

    Do you have a pic of the rotary valve that you use? Is it thicker or thinner than stock? Lighter or heavier?

  4. #4
    Work Harder, Millions on Wellfare Depend On Us! ultramaxracing05's Avatar
    Join Date
    Aug 2009
    Location
    Beaumont, Texas
    Posts
    2,999
    +1
    123
    buy one or borrow one from someone that might have a spare, it will save you the hassle from finding the right blueprint. where are you located. I'l let you borrow mine.

  5. #5
    blowbyu's Avatar
    Join Date
    Jun 2006
    Location
    San Antonio, TX
    Posts
    635
    Quote Originally Posted by dghal View Post
    The key being you would need blueprints,,

    I just use the Carbon Tech Rotary
    I would use the factory rotary valve. Carbon ones break and chip.

  6. #6
    Work Harder, Millions on Wellfare Depend On Us! ultramaxracing05's Avatar
    Join Date
    Aug 2009
    Location
    Beaumont, Texas
    Posts
    2,999
    +1
    123
    friction will also be a factor. I never touched or experimented with carbon fiber, but you will have some scoring going on.

  7. #7
    The carbon ones absorb fuel and swell up and then drag. Will ruin the rv surface and strip the brass gear.

    My brother has a wire EDM also. It is 8ft by 8ft. Came from the Houston space center and actually cut parts for several space shuttles.

  8. #8
    Mark22's Avatar
    Join Date
    Sep 2009
    Location
    Springfield, MO
    Posts
    191
    EDMs are awesome tools to have. Ditto for a waterjet. I cut some emblems for my boat last year out of 16ga stainless. They're still for sale if anyone wants `em. This is just the kind of stuff an EDM can do. I'd love to be able to make something for my ski with it. Any ideas??
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	1.jpg 
Views:	66 
Size:	3.6 KB 
ID:	151453  

  9. #9
    Work Harder, Millions on Wellfare Depend On Us! ultramaxracing05's Avatar
    Join Date
    Aug 2009
    Location
    Beaumont, Texas
    Posts
    2,999
    +1
    123
    sponsons!!! make me a pair too

  10. #10
    96XPSS's Avatar
    Join Date
    Feb 2006
    Location
    Warner Robins, GA Home of the 2007 All-Star Little League World Champions!
    Posts
    4,361
    Buy a stock valve, and duplicate it if you want. Rossier made a defferent degree RV back in the day, to make up for their inferior bog (which I eliminated using the stock valve) on low end. It gave up max rpms though. There is always a trade off in performance to gain on one end, you lose on the other.

    So the stock, steel RV, by far, is the best.

Page 1 of 2 1 2 LastLast

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Spherical Rotary Valve Engine !
    By RX951 in forum Yamaha Open Discussion
    Replies: 7
    Last Post: 11-21-2008, 04:40 PM
  2. rotary valve
    By evil4g63 in forum 2-Stroke Performance
    Replies: 0
    Last Post: 06-19-2008, 10:02 AM
  3. Water behind intake manifold/rotary valve cover bolt
    By DarthAWM in forum 2-Stroke Performance
    Replies: 4
    Last Post: 05-04-2008, 08:30 PM
  4. rotary valve timing question
    By hotrod_sxty8 in forum 2-Stroke Performance
    Replies: 4
    Last Post: 09-02-2007, 10:17 AM
  5. New Coated Valves and Springs
    By 1 FAST VE in forum 4-Tec Performance
    Replies: 3
    Last Post: 05-28-2007, 07:01 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •