The ground up yz/wr/xt/tt adventure build

Discussion in 'Thumpers' started by yamahaman, Oct 27, 2010.

  1. Zecatfish

    Zecatfish XTique Rider

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    Have you looked or thought about the secondary snorkel issue your going to have from the Shock Resevoir?
    I was looking at something similar for the XT350 and mating a YZ490 suspension to it.
    I remember reading mothef's issues with his build and building a new snorkel.
    #21
  2. B.Curvin

    B.Curvin Feral Chia Tamer

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    #22
  3. yamahaman

    yamahaman wannabe bike builder

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    MTOTHEF
    here is what I am planning!
    The manifold is just taped on with duct tape so it is protruding out in to the engine area a bit to much (just done this as a representaion). This manifold will be one of the last things I do because I has to wait untill the motor is in the frame. This is one of the reasons why I put the wr subframe on the tt frame. As the air box and air duct was premade so this made half of the job easier. I have poured over your build and I am trying to find a suitable solution to the lower linkage and the position of the bolt frame relationship I have an idea but it's a bit confusing to explain so keep your eyes peeled

    [​IMG]

    This is a repesentation ony the carb is only supported by the rubber boot so it is drooping down a bit but you get the general idea as what is going on

    :1drink :1drink :1drink
    #23
  4. mtothef

    mtothef Been here awhile

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    yeah, the lower link can be a pain, but you are at least going about it with a fair bit more forethought than we did. still, is the tt lower main frame about the same as the xt - as in, fuck all places to maneuver when it comes to placing the lower link? if so, i feel your pain. remember, if it all goes wrong down there, i can at least recommend spring rates to compensate for the leverage discrepancy. :lol3

    as for the carb, is that an intake off a yamaha quad? if you can adapt some way of allowing the carb to mount into it on an angle, you should be golden. i was looking for one of those to play around with during my build, but came up empty handed. really interested to see how it all comes together for you.

    by the way, that's a super nice way of dealing with the front end. takes care of the xt frame having a short headtube, bearing differences, steering stops, AND a place to mount a steering damper all in one pass. mighty nice!
    #24
  5. yamahaman

    yamahaman wannabe bike builder

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    #25
  6. yamahaman

    yamahaman wannabe bike builder

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    I was trawling around and I found this

    http://www.horizonsunlimited.com/hubb/yamaha-tech/my-1990-2003-xt600e-mods-43008-8

    Turns out the single carb got too hard for old mate not so sure about the k&n filter in the dirt, they have been attributed to a few engine blow ups here due to the drought conditions over the last few years (inadequate filterage)

    Check out the duct work made of plastic??????:puke2
    #26
  7. mtothef

    mtothef Been here awhile

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    ah yes, our azorean friend with many questions and imaginative capabilities unburdened at times by the constraints of reality. i was wondering how his progress had been going...

    regarding carb placement, if i recall, the 2-1 manifold pushes the carb back a bit, and there will be some interesting space/fit issues to contend with there. another option you could consider would be trying to find/fit a shock with a remote reservoir, which would allow you to route boots around both sides of the shock if you ended up having to revert to the twin carb setup.

    if i had the chance to do it all over again, i would probably try to wedge a ktm swingarm in there and go linkless with the shock offset to one side. crude, and not as good a suspension as a properly designed linkage, but a no-brainer with respect to the carb and airbox...
    #27
  8. yamahaman

    yamahaman wannabe bike builder

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    Well I managed to get the donor bike/engine running today after a new set of rings and valve stem seals so this made room on the bike stand for the project build.
    [​IMG]

    So I have had some expert input from a couple of scottish/irish/italian friends of mine who's input has been invaluable. Some good ideas from these two nutbags. Managed to work out the linkage angles for the lower dogbone and I have a solution for the lower bolt removal but all I did was prepare for the linkage to be installed and prepared the tubing to fit the wr subframe

    [​IMG]

    All I have to do is tack this tube in and make the lower sub frame mounting points and the lower linkage mounting points. Easy!!!!!!!!!!!!!!!:1drink :1drink :1drink :1drink
    #28
  9. mtothef

    mtothef Been here awhile

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    i was all set to post how you might want to test fit the engine before you get all carried away with that placement, then i realized what you had done. nice scalloping out of the right side plate there! very clean, you'd hardly notice it wasn't stock.

    crafty...:evil
    #29
  10. yamahaman

    yamahaman wannabe bike builder

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    When we (myself and two experts) put the bike on the work stand we noticed that the two frame rails are asymetrical the right side has more of a curve to it and it was not necassary to cut any thing from the frame this is how it was. I have managed to get the lower link into place (almost) it is only 5mm (3/16 in) in front of the original position. This is going to have little or no effect on the suspension travel all the forward position does is raise the frame off the ground by about 3mm (1/8 in). The linkage/swingarm and shock location relationship is identical to that of an 04 yz/wr which was the donor swing arm and linkage.

    [​IMG]

    I have tested the suspension through full range of movements and all is good (so far) seems to be all ok

    I have welded a piece of tube onto the frame (rather than change the subframe) so I can mount the subframe onto the frame un-modifyed this was done so that if I damage the subframe on my travels one can be purchased or shipped to my location and fitted straight up.

    [​IMG]

    All that is required is to make the tags to mount the lower portion of the subframe and weld them on.

    Please excuse the poor welding I was having problems with the mig at work it has a hard life and gets no maintenance so when I make the final brackets I will investigate the problem and give it a bit of maintenance.

    :1drink :1drink :1drink :1drink
    #30
  11. yamahaman

    yamahaman wannabe bike builder

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    So I got home and put the back end together and was putting some thought into the fuel tanks??? yeah I got a rear sub tank and I was messing around with the set up of the bike and I put the ex-army main tank on the bike and it looked absolutly terrible! SO BAD I DARE NOT POST PICTURES. I started to mess about with some wr tank shrouds and I think I am going to make my own tank out of aluminium (this is my vanity) using the shrouds to make it look pretty.

    [​IMG]

    Yeah its a pretty poor representation of what im going to do but computers are not my speciality

    [​IMG]

    Here is the rear end set up for the big girls long distance rig any input for the tank setup would be appreciated

    :1drink
    #31
  12. a1fa

    a1fa Throttle Jockey™

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    #32
  13. andyhol

    andyhol volcano rider

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    this mate is way TOO SEXY for its own good. i wish i had a bike this when i was working up north chasing cows through the bush............:clap
    #33
  14. PhiSig1071

    PhiSig1071 What's ******width?

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    Your work up to this point looks amazing, but I have to ask, what's with the exhaust can mounted pointing up like that? I've seen it on Rally bikes, but I would think it would create problems. To me it would be more prone to collect water, harder to expel water and it would have a lot more bends in the mid-pipe, which would reduce exhaust flow. What am I missing? Obviously there's a reason for it.
    #34
  15. mtothef

    mtothef Been here awhile

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    go on, run a low pipe, you know you want to!
    #35
  16. yamahaman

    yamahaman wannabe bike builder

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    The exhaust is here because when it is more parallel to the ground it is very vulnerable to crash damage, when it is here and you lay the bike on the ground and it contacts the ground in a more even manner

    [​IMG]

    When the pipe is low and parallel to to the ground to clear all of the swing arm and pivots it protrudes ou too far and the end of the pipe is way past the rear axel. Just looks weird, wobbles heaps and is vulerable to damage


    Oh and I like the way it looks!

    :1drink :1drink :1drink
    Off to see crowded house tonight at rod laver arena
    #36
  17. PhiSig1071

    PhiSig1071 What's ******width?

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    Gotcha. I figured there was a reason, just couldn't figure out what it was.
    #37
  18. BIG ED XT FAN

    BIG ED XT FAN Long timer

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    #38
  19. trackhead

    trackhead Utard Wankster

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    When people do the low pipe thing, does it change engine tuning or back pressure dynamics at all?
    #39
  20. mtothef

    mtothef Been here awhile

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    there's a lot of variables in response to your question. ideally, the pipe routing shouldn't make much of an impact on pipe tuning at all. theoretically, a straight pipe with no bends at all in it will be the most efficient at getting exhaust from the valve to the other end of the tailpipe, but if the bends are done without kinks or sharp changes it has been proven that some mighty twisted spaghetti bowls do a fine job as well.

    header pipe diameter has a huge impact on tuning - larger headers generally allow better wide open throttle behavior, but usually at the expense of lower rpm power and throttle response. smaller headers, within reason, do the opposite. total length of the pipe also has some impact on tuning, as does how much the pipe widens or constricts at the muffler end of things.

    my reasoning for going with a low pipe was purely about looks. if anything, i have lost some power, and am in the midst of jetting it back into the right ballpark.
    #40