Carb adjustments for trail riding, TLR200

Discussion in 'Trials' started by Irish John, Jun 3, 2013.

  1. Twin-shocker

    Twin-shocker Long timer

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    I would advise that the best possible alteration for any TLR still equipped with EPA type induction system parts is to remove them and fit Taiwan made carb that comes perfectly jetted for the TLR, and remove flame trap from stock air box, and fit pod type filter. Its very very difficult to tune a carb if its worn out (which many OE ones are), and if you have fixed pilot its impossible, unless you have machining facilities to get that sorted. Last time I bought one the Taiwan carbs were around $24.
    #61
  2. lineaway

    lineaway Long timer

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  3. Twin-shocker

    Twin-shocker Long timer

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    The Taiwan carbs are available from Shedworks and from Ebay. They are a genuine bolt on replacement, and in combination with removal of the flame trap, and intake silencer are something that really does improve the way a TLR runs.
    #63
  4. UtahGuido

    UtahGuido Long timer

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    So where is this flame trap? As far as I can tell there's the cylindrical grating arrangement around which the filter element fits, and then the intake passage into the carb. If I remember correctly when I stuck my fingers in there I felt the innards of the carb - nothing that might be a flame trap or a backfire screen.
    #64
  5. Twin-shocker

    Twin-shocker Long timer

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    The metal gauze cylinder which the OE foam filter fits over is the flame trap. This tends to very much reduce flow at higher rpm, and removing it as well as the intake silencer parts is a good way to increase performance.
    #65
  6. UtahGuido

    UtahGuido Long timer

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    Got it, I think. I'll figure it out when next I'm in there.

    I did remove the intake silencer and the bike went from starting on the first or second kick with little choke to starting on the second or third kick with full choke, to yesterday not starting at all with a fouled plug. I will not whine about having no time at the moment to tear into this thing but I sure am looking forward to a couple days free to get this carburetor sorted out.

    BTW the carb offered by Shedworks (I assume its the chinese unit of which you have spoken) is offered at £80, plus post. I'm thinking OEM rebuild kit.
    #66
  7. Twin-shocker

    Twin-shocker Long timer

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    I would suggest taking a close look at your carby.............it seems to me like you may well have a porous float? The carbs sold by Shedworks are made in Taiwan, and while quite as well made as OE are pretty close. They can also be found on Ebay for $24.

    The flame trap removal is not difficult and simply requires a stub making which faces into the air box, and fits into the intake hose, which a KN or foam type pod filter can be fitted to.
    #67
  8. UtahGuido

    UtahGuido Long timer

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    Something is dreadfully wrong for I can't
    Kick the bike over without
    Fou-ow-ling the plug...

    Marty Robbins just took a few spins in his grave.

    Tomorrow the carb comes out.
    #68
  9. Twin-shocker

    Twin-shocker Long timer

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    Might be an idea to check whether you have a perforated float? You dont even need to take carb off bike to do this, and it takes less than 5 minutes.
    #69
  10. UtahGuido

    UtahGuido Long timer

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    So Iron John, what was the outcome of your high altitude jetting experience?
    #70
  11. Sting32

    Sting32 Trials Evangelist

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    I could be out of line, but I think he hasn't gone yet, or might be out there now? He was supposed to make it to our event week before last, that is the last I heard from him for a while now.
    #71
  12. UtahGuido

    UtahGuido Long timer

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    While we're waiting for IJ to check back in I will share with you that I fixed my plug fouling problem. My buddy Tom stopped by (on his very loud Suzuki Intruder) and just Tom's presence seems to clarify most mechanical and/or electrical problems. I explained my problem, that being the fouling of the plug after merely kicking over the machine, and his diagnostic strategy went something like this: "It worked before, right?" Yes. "And then you made a change?" Yes. "Try undoing the change." See, Tom is a genius.

    What I had done was take out the baffle/snorkel/organ pipe thingy from the air box leaving that 2 inch square hole behind which hole I then proceeded to plug with a bit of air filter foam, figuring that more air filtration had to be a good thing. Uh, nope. Basically it had the effect of sticking a sock in someone's mouth and holding their nose. The poor little beast couldn't breathe! So out came the offending filter and voile' - after a few kicks she (he?) roared to life. Amazing how sensitive that ai/fuel mixture can be, and how dense I can be. Now it starts first kick again. The plug is still blackish and Tom's suggestion is that I remove the air filter altogether and run it around for a while in the clean urban mountain air we are blessed with and see if the plug lightens up. Might do that later today.
    #72
  13. laser17

    laser17 Been here awhile

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    Great write-up UG!
    #73
  14. UtahGuido

    UtahGuido Long timer

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    Thanks Laser. Hopefully we can learn from each other's misadventures!
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  15. lineaway

    lineaway Long timer

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    +1 for being honest.
    #75
  16. Irish John

    Irish John Been here awhile

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    Long delay in getting back to everyone on this thread. I did indeed take the TLR out to CO for a week of riding. I never did locate the necessary jets. That said, aside from being a bit harder to start and of course down on power, it ran just fine.

    I ended up playing with idle/air mixture screw when I got to camp. Elevation there is approximately 7200 ft. In crossing one pass, at 11,000 ft. I made the mistake of shutting the engine off to take some photos. Very hard to get it restarted. I ended up coasting down and bump starting it although it took a couple tries. Because of that experience, I'll not take it back out the CO to ride again unless I can rejet it. My leg is still tired from kicking it over.

    A few mods were made for the trip. Installed some bark busters, I fabbed up a rear rack and had an extra seat pan redone into a long ride seat. The later worked pretty well but I want to have it redone again with stiffer foam. For riding around KS, I had installed a 14T countershaft sprocket. I took the stock 13T with me and ended up putting it back on out in CO.

    While in the mountains, I averaged about 110mpg. I did carry a couple 1 liter MSR fuel bottles in a tail bag I put on the rack. If I can get the jetting and seat sorted, the TLR would make a really nice little trail bike.
    #76
  17. UtahGuido

    UtahGuido Long timer

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    Cool. 110 mpg? Wow!

    And yeah, that carburetor... seems to be a bit of a crux issue with these bikes.
    #77
  18. Irish John

    Irish John Been here awhile

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    I am very seriously considering swapping for a Mikuni. Much easier to find jets.

    Yea, I was shocked by the gas mileage. Of course your mileage may vary, but I have found that mpg seems to jump up at the higher elevations in CO, but 20+ mpg was shocking.
    #78
  19. Twin-shocker

    Twin-shocker Long timer

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    Mikuni VM22 will fit the TLR, but needs to be modified slightly. The best possible option is a Taiwan made direct OE replacement, which I think are currently selling for around £24. Comes jetted perfectly, and is direct bolt on replacement part.
    #79
  20. Irish John

    Irish John Been here awhile

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    Twin Shocker, where can I find one of these Taiwan copies?
    #80