Overgrown Offroad Zombie

Discussion in 'Some Assembly Required' started by larryboy, Sep 18, 2011.

  1. larryboy

    larryboy Chopper Rider

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    Motion "Pro" provided a splitter, single from the throttle tube to splitter, two cables from there to the carbs.
  2. kellymac530

    kellymac530 motorcycle addict

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    Larryboy,
    What a great build and thanks for posting this link in my frame thread. Been a great read and some great things to look for and look OUT for if I do a similar build.

    As far as the slide opening under less spring preload, I am curious how that happens with a push pull throttle? The can not move if the return cable is set at the right tension....at least as far as my experience with the flat slide carbs on my Yz450s and KTMs.

    In the desert we often run with only the pull cable if we bust one. We use the push/return cable like it is a spare cable.

    It seems like I saw a Harley in your garage in one pic, they have very drag on the throtlle and sometimes require you to manually return the throttle, that always works. Not saying you would ever want to use that in the dirt, manual return I mean, but a lighter spring on the throttle return springs should not stop the return.

    I agree with Pool, if you use a block and tackle or different leverage system for the throttle Ys that would work, but it will definately add distance to the twist of the grip.

    On my KTM 530 EXCR I went to Moose throttle tube with different cams on the lobe for shorter throttle pull more like a MX bike. I never like the long twist on the EXCR, it was almost 180* rotation for full throttle. With the switchable cam systems I was able to get it down to about a 90* full throttle twist and it reall added to the snappy feel of the bike, more MX/SX bike like I am ussed to.
  3. larryboy

    larryboy Chopper Rider

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    Good points, kellymac!! I don't have a ton of experience with these carbs, but I tried reducing the spring pressure past the last adjustment nub and at idle without a hand on the throttle it revs itself. With a hand on the throttle tube I can use the push cable to hold the idle. Like you say, manual return isn't what you want on a motorcycle and it's downright dangerous.

    I haven't done anything to her, just been riding it.

    Last trip:

    http://www.advrider.com/forums/showthread.php?t=842291


    [​IMG]
  4. kellymac530

    kellymac530 motorcycle addict

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    I am wondering if changing to the different cams on the Moose style TT would help or hurt????

    It sounds as though you have already tried to take some tension off of the rotary springs on the carbs themselves with little effect.
    I am wondering of eliminating those round springs on the carbs themselves and trying some slightly longer but softer straight springs, more like an old car carburetor would use, might work.
    My reasoning, possibly flawed, is that a rotary spring must have a certain amount of preload to be effective and the rising rate of the spring is pretty steep making a tough pull when that is doubled on your twin carn setup. Whereas a longer straight spring could in effect have the same initial tension but by being longer you could keep the pull tension a little more linear...I hope that makes sense...?

    On one side carb that might be easy, but on the one side that the linkage arm is outboard this may not work very well with a long spring sticking out in space....Possible with some finagling and planing though. Might be worth a try.

    I am absolutely sure you have checked and double checked but it may be worth a mention, have you made sure there is no bind on the cable anywhere? Rotated the throttle tube with the ends both disconnected fron the carbs to make sure there is not some pull or friction adding to the issue?

    I think the issue stems from just having 2 carbs pulling on your hand.

    You are a real inspiation for me right now...I am close to pulling the trigger and stripping my RT down and going for it.
  5. larryboy

    larryboy Chopper Rider

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    That's about what it boils down to. In hindsight I should have gone with CV carbs, but these things were only $250 each and brand new. On the plus side, if I swap the BringMoreWrenches over to CV's I can use the TM's on a couple of XRR's. :wink:
  6. kellymac530

    kellymac530 motorcycle addict

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  7. kellymac530

    kellymac530 motorcycle addict

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    NOOOOOOOOO

    I hate CV carbs and would NEVER consider riding any real dirt with them again....I almost got killed 3 or 4 times on a KTM that had a CV carb on it, a 2000 SXC 400 Lc4 motor bike had one on it for smog reasons and the bog out on any hard hit in the dirt. Not even jumping it, just any hard G-out where the suspensing compresses hard or bottoms out the vacum slides slam shut causing the carbs to right when you need acceleration to drive through the G-out. Instead it bogs and causes the rearend to buck violently spitting you over the bars...all fixed with a $400.00 Sudco kit. Never happened again and ran WAY better.

    You still would have a return spring on a CV carb anyway on each carb so I am not sure it would stop the issue you are fighting.....not sure though.
  8. larryboy

    larryboy Chopper Rider

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    I ain't jumping this thing, the earth would crack right down the middle if I did. :lol3

    Return spring on a CV doesn't have to return the slide, just the throttle plate, that's why the spring is so small on the CV carb...like BMW used to do their bikes, CV Bings or whatever they used.
  9. kellymac530

    kellymac530 motorcycle addict

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    No I know you are not "planning" on jumping this thing, but sometimes you hit whoops hard or there is a washout you do not expect or other odd scenerios, that is WHY you added more suspension Right?

    It does not have to be a jump, ANY harder hit can close those slides, not sure about the diaphram Bings, I am talking about the Mikuni CVs like a Harley has or most DRZs....I would not run those on a battle scooter.

    I have an '86 R80G/S that has the Bings on it with the vacum diaphrams on it and those are NOT that easy to pull either. The throttle is alot tougher twist than my R1100RT FI is. My KTM 530 with the FCR flatslide carbs similar to yors was VERY light throttle pull, albeit only 1 carb.

    I hope you find a fix to lighten it to a more comfortable pull.
    Keep us posted
  10. larryboy

    larryboy Chopper Rider

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    Nope, it doesn't have any more travel or ground clearance than it did before...it's just lighter and the front suspension travels like a motorcycle now.

    I had a KLR with the same carb that a Harley has, CV and I never slammed the slide closed on it during a g-out.
  11. kellymac530

    kellymac530 motorcycle addict

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    Larryboy, I love Social D and Mike Ness. On almost all of my other regularly visited forums my sig line is "Your shakin my hand while your pissin on my leg" Mike Ness" That is one of my favorite lyrical quotes of all times. A bit synical but often true unfortunatly.
  12. Racegun

    Racegun Single Track Mind!

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    Howz the bike working out?
  13. larryboy

    larryboy Chopper Rider

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  14. larryboy

    larryboy Chopper Rider

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    All loaded up for a long weekend two-up.

    [​IMG]


    We're chatting about what a great bike I've created here and how we're gonna keep it for awhile.

    [​IMG]


    I run the bike while I air up the mattresses, but the bike dies and won't idle anymore. Can't be fuel, ran fine all day. Can't be air, filter is clean. Must be spark, runs poorly...thinking plug wire or a fouled plug.

    [​IMG]


    Fiddled around with it, checked this and that...screw it, it still runs, let's limp it home.

    [​IMG]


    Left cylinder is cold...:cry

    [​IMG]


    Made it home, plug wires ohm as good. Pickup and ignition box are good, need to pull the coil and test it out...98% sure one side of the dual output coil croaked, totally my fault...it was a $14 part and I should have bought a better quality one. Note to self; carry a spare coil.


    Next round of mods is coming up...3.20 rear gears in place of the 2.82's, more fuel capacity and stiffer springs front and back.
  15. slackmeyer

    slackmeyer Don't mean sheeit. .

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    Nice to see that it's still getting used now that you've got the 100mph sofa in the garage. . . .

    I think I'll be up in that area on bear valley road tomorrow.
  16. larryboy

    larryboy Chopper Rider

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    Yup, it's a great bike!! Oh yeah, just put a new starter on the thing too...got tired of hearing the screeching sound everytime I started the engine and it really made me think of walking all the time. :lol3

    Have a good ride!!

    :ricky
  17. slowpoke69

    slowpoke69 Been here awhile

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    I love this bike, you definitely created a monster. It looks GREAT too, without the beak and all. The exposed driveshaft on that one bike looked sweet. After reading this I've no doubt you can do it.:clap:clap

    I'm trying to find an 1150 myself, I like the fact the you can work on them yourself, less money going to the dealer, plus it's a good feeling knowing that it runs due to your own work.

    I'm off to read a couple of your RR's now, stay safe.:D
  18. duxrneet

    duxrneet Been here awhile

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    Ha, and I thought the zombie was running like an un-dead racehorse, hence the quiet thread....

    Good to see it's nothing major, though.:D
  19. Coachgeo

    Coachgeo Diesel Adventurer

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    in AWE. Great thread, great fabrication, great patience. I only can hope that between me and Curtis I end up with something as sweet.

    PS- and thanks for the info earlier.
  20. larryboy

    larryboy Chopper Rider

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    It's been quiet because it's been done and sits awaiting the next trip. :deal


    Went through some super old emails looking for the coil that Poolside had suggested I use...found it, Dyna 3 ohm dual tower DC6-1. Of course I asked him if I could just use a stock Harley coil at $14 instead of the $85 Dyna coil, get what ya pay for I suppose. :lol3


    Thanks Coach and slowpoke, can't wait to try out the new final drive with the lower gears.

    Might rebuild the driveshaft while I have it apart, over 60,000 miles on the bike now.