2 into 1 exhaust?

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by BigMac, Jul 15, 2005.

  1. BigMac

    BigMac Been here awhile

    Joined:
    Nov 12, 2004
    Oddometer:
    321
    Location:
    Vacaville, CA
    I know a few fellow 950 owner's and DIY guys had mentioned in the past about fabricating a 2-1 setup on the 950, I had been planning the experiment myself but unfortunately just have not found the time even though I have a friend with the mandrel tubing bender, SS tubing and TIG welder. The projects greatest appeal is opening up the left rear side of bike for a 3rd petrol tank of maybe 8-10 liters which may result in 250mi fuel range...or at least that is my optomistic hope. Anyway, Summer is here, my son and I are looking to do some riding in Central America and I'm still handicapped with 150-160 mile fuel range...maybe 175 if I really nurse her along.

    So, has anybody successfully completed their 2-1 exhaust? If so, would you be interested in your 1st customer? If not, at least be willing to share your experiences, design, pitfalls and maybe success? Take care.
    #1
  2. k7

    k7 Almost retired....tick..tick..tick..

    Joined:
    Jul 15, 2002
    Oddometer:
    24,825
    Location:
    Aridzona
    Wish I could help - it's an admirable goal but is a 150-180 mile range really that much of a handicap? I've traveled in Mexico, Guatemala and Belize and was never (overly) concerned about running out of gas.

    I'll admit I've purchased gas out of a barrel but another 50-miles wouldn't have made a difference in those instances. No flames intended!
    #2
  3. CraigTransalp

    CraigTransalp Been here awhile

    Joined:
    Oct 29, 2004
    Oddometer:
    137
    If you have the cash, these guys will do the 2 into 1 section at very high level of quality. Smooth as a baby's bottom inside and outside welds.
    www.burnsstainless.com
    #3
  4. autorotate

    autorotate Adventurer

    Joined:
    Mar 31, 2005
    Oddometer:
    91
    Location:
    El Paso
    244.3 miles till bone dry


    Configuration: Myself (230 lbs) and the KTM 46L topcase loaded with 25lbs.

    Environment: 50% Paved, the other 50% a mix of gravel/dirt roads.

    Had a gas can, and had to see for myself what the range was.

    Low fuel light came on at 169, 173, and finally stayed illuminated at 177...


    Puttered to a stop and the trip odo read 244.3 miles
    #4
  5. AntWare

    AntWare Lost In Translation

    Joined:
    Oct 10, 2002
    Oddometer:
    16,483
    There was a fella here, I think from one of the Scandanavian countries that had done a nice job on the single exhaust.

    I reckon only having a spare fuel cell on one side might fell odd, especially as the weight fluctuates from full to empty (20lb swing). It would likely need it's own fuel pump as well.

    I've done 220+ and never ran out, might have to try Auto's experiment one day.
    #5
  6. Mack

    Mack Gone, but never forgotten. RIP, Mack...

    Joined:
    Sep 7, 2002
    Oddometer:
    3,797
    Location:
    Austin, Texas USA Native Oregonian
    I had emailed him, and he cross posted to http://www.monomaniacs.nl/smf.htm (might have been 950owners site, but I'm 99% it was mm.) Can't find any of it now.
    #6
  7. autorotate

    autorotate Adventurer

    Joined:
    Mar 31, 2005
    Oddometer:
    91
    Location:
    El Paso
    #7
  8. Fresno

    Fresno Adventurero

    Joined:
    Dec 11, 2004
    Oddometer:
    617
    Location:
    Fresno, California
    I don't think thats what he meant. :rofl
    #8
  9. JediBri

    JediBri Glory to GOD

    Joined:
    Sep 12, 2003
    Oddometer:
    513
    Location:
    Colorado
    Ditto. Shouldn't the 950 be well into the 200s before running out? When Bike did the adventure test last year they had the warning light listed at 170mi and out at 256mi...

    Brian
    #9
  10. Flanny

    Flanny Flanny-it-up!

    Joined:
    Feb 18, 2003
    Oddometer:
    2,739
    Location:
    Ottawa, Ontario, Canada, the World, the Universe
    I need extra range. I can only get about 320 kms out of a tank, and no, that is not enough around here. We often explore areas where it is 280-300 kms to known gas, but with an uncertain route to get there. If we travel 230kms, only to find that a beaver has dammed the road, we need to go back! So, the stock range is not enough.

    We've taken to carrying extra fuel strapped onto the back rack on onto the saddle bags. It's really not that bad...but it's certainly less safe, and not optimal weight placement.

    I would kill for a "low" routed 2-into-1 like on the 950 Rallye...

    [​IMG]
    #10
  11. Mack

    Mack Gone, but never forgotten. RIP, Mack...

    Joined:
    Sep 7, 2002
    Oddometer:
    3,797
    Location:
    Austin, Texas USA Native Oregonian
    #11
  12. SQD8R

    SQD8R Eat squids and be merry

    Joined:
    Jun 16, 2004
    Oddometer:
    7,481
    Location:
    The Village: 52.9144° N, -4.09615° E
    I looked into doing a 2-1 on my RC51 (R.I.P.'s:cry ) like the 1st season AMA bikes were some years back. I checked with local fabricators, living in Windsor, Canada's motor capital, had some advantages, and found that it could be done relatively easily and @ less expense than a pro-job. Also a racer in the Canadian Race series has an RC51 with this configuration. I'm headed to MoSport for the 3rd round tomorrow. If he's there, and still using this configuration, I'll get some pics for you. While not the same degree of angle it can provide for some basics. If nothing else you may have a starting point for some ideas.
    #12
  13. SQD8R

    SQD8R Eat squids and be merry

    Joined:
    Jun 16, 2004
    Oddometer:
    7,481
    Location:
    The Village: 52.9144° N, -4.09615° E
    sorry boys, the guy I knew who did it on the RC51 has switched to an underseat exhaust this season. Good luck with this endeavour and keep posting updates pls.
    #13
  14. BigMac

    BigMac Been here awhile

    Joined:
    Nov 12, 2004
    Oddometer:
    321
    Location:
    Vacaville, CA
    Well since it appears nobody has yet actually built such a system, I'm volunteering to be the guinea pig. In order to get the design hopefully close to ideal for scavenging purposes, I need some engine specs. I already know the cylinder angle, valve sizes and header OD, I cannot however find the cam specs nor port size and shape. Yes, I could simply take things apart and measure but I'm hoping somebody may have the info such that I can still ride my bike while I'm designing and fabricating the new system. I need intake and exhaust port diameters and shape or cross-sectional area, the cam lift for intake & exhaust, cam timing (degrees) at lift centerline, intake and exhaust duration at 0.050" lift or where duration is measured and cam timing for opening of intake and exhaust valves (degrees btdc/atdc).

    If I can recieve the above info by end of this week, I will have a prototype 2-1 system installed and operating by August 1. Please help the cause if you have access to this info.

    As for exhaust can, no problem. I'm going to use a Scorpion SS can designed for R12GS. It's an 18" perf core straight through design that can easily accomodate the exhaust flow of a 950 twin. I'm even going to remove the end cap to install a Pro Moto billet endcap which features a USFS approved spark arrestor and a removable throat collar to attenuate noise levels to within 92db EU regs. Once system is built and has been dyno tuned, I will be happy to share all specs and materials used by posting them on this board. Take care.
    #14
  15. AFekete

    AFekete Long timer

    Joined:
    Apr 9, 2002
    Oddometer:
    3,208
    We're working on the rally two into one setup...stay tuned..

    thanks,
    Andrew
    #15
  16. K2m

    K2m ....58....

    Joined:
    Feb 27, 2005
    Oddometer:
    2,238
    Location:
    Sydney Australia
    I can hardly wait BIG MAC ....... I just wish I could help:clap


    Once the exhaust is sorted we can work on rear fuel tanks FLANNY :smile6
    #16
  17. Flanny

    Flanny Flanny-it-up!

    Joined:
    Feb 18, 2003
    Oddometer:
    2,739
    Location:
    Ottawa, Ontario, Canada, the World, the Universe
    I just scored a second facftory exhaust and a rear sub-frame on E-bay :deal

    Let the games begin... :evil

    Andrew...I wouldn't mind being a guinnea Pig with my new-found spare parts to trash... :deal
    #17
  18. Stephen

    Stephen Long timer Supporter

    Joined:
    Feb 19, 2002
    Oddometer:
    3,445
    Location:
    Austin, Texas, USA
    Most of the time I've spent staring at my 950 has been while trying to suss out a low route for the pipes. The front's easy. The rear ain't bad, but ends up with some odd angles, and kinda short, with a sharp turn at the collector. I'd like to see some decent pics of the rally exhaust, haven't found any.

    My motive is, apparently, different from the rest of y'all: I've gotten 220 miles (365 km) from a tank without suckin' it dry, which is pretty much enough for me. However... I can't stop thinkin' about gettin' luggage four inches closer to the centerline of the bike. Oh, it could be sleek. Same capacity as the Gooobi's, but so slim that you wouldn't even bother takin' it off when you didn't have a load. That means I'm not interested in the rally-style upswept silencer. Just need a can near horizontal behind the collector.

    Of course, I'll have to say bye-bye to the centerstand, unless I get really damn clever and cantilever the base of it off a single upright. Might be feasible.

    Anyway, I'd like a low pipe.
    #18
  19. K2m

    K2m ....58....

    Joined:
    Feb 27, 2005
    Oddometer:
    2,238
    Location:
    Sydney Australia
    STEPHEN
    This photo of the Duke exhaust may help

    Equal length headers would improve the torque higher up the RPM range. At least I am assuming this in the case of the Duke

    Unequal length headers are designed to spread the torque by having one cylinders scavenging tuned for the mid range and the other for further up the rev range. This is would good for desert racing........ (What fun this is :D )

    [​IMG]
    #19
  20. Jeepboy

    Jeepboy Roost

    Joined:
    Feb 9, 2005
    Oddometer:
    560
    Location:
    Champaign, IL
    Why are the race exhausts not made or the design not avaiable? Seems silly to reinvent the wheel when its already been done. On that note, is there any documentation of the exact differences between the dakar race bikes and the stock 950s? Maybe we cannot have all those go fast goodies, but it sure would be interesting to see what changes were made for racing.
    #20