Trials conversions

Discussion in 'Trials' started by plane_ben, Mar 7, 2011.

  1. plane_ben

    plane_ben Adventurer

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    Anyone out there in the trials world that remembers a trials conversion using a '72/'73 XL250 Honda? I have access to a pretty cheap XL250 and was thinking of doing such a project.

    I know, I know. I could find a cheap TL250 and save myself the trouble. But I like doing stuff the hard way.:D
    #1
  2. grizzzly

    grizzzly The Pre-Banned Version

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    i am pretty sure that i have ridden one back in the day and honestly i think you would be better off trying to convert a 250 ninja into a trials bike and you wouldnt be killing an old thumper, i have put a 54 tooth rear on my 82 xl500 and that does make it slow but it still wont turn or balance very well, and the clutch is not meant for that type of abuse, and when you get it into the tight stuff it develops this buick like feel
    #2
  3. lamotovita

    lamotovita Ageing Adventurer

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    Any bike is a Trials bike, if you ride Trials on it.
    Gear it down, grind the steering stops, put good tires on it and go!
    #3
  4. Brunow - 007

    Brunow - 007 Bantam Fever

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    Hell yeah!... Would be cool to win a trails event on a 250 ninja :D
    #4
  5. plane_ben

    plane_ben Adventurer

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    :rofl:rofl:roflThat Ninja stuff is pretty funny. But in reality, trials motorcycle were developed over time from regular motorcycles modified for the task. Being a Honda mechanic back in the mid '70s I owned and rode both XL and TL 250s. XLs had a heavier flywheel and different internal gearing, TL had a smaller carb. But overall they were identical. Most of us that rode the TLs in compertion bored our cylinders for 305cc and stole the flywheel off an XL for better grunt, a little trick I learned at the Honda tech center in Gardena. The factory trials and MX teams were right next door to the tech school building.

    Anyway, with that being said. I'm more interested in a trail bike with some minor trials ability, than a trials bike. I had two modern trials, a Gas Gas and a Montesa 4RT. They are not to trail worthy when you can't sit down, and I'm old.:D I also have a pretty ragged XL250 of '72 vintage that would be a money pit to restore, but would make a nice trials/trail bike conversion. Our trials club would let me ride the vintage twin shock class on it, and they ride the novice sections. So it wouldn't be like I was going after some big narley sections, doing the stop and hop type of riding.

    I do remember a cycle mag did an article on this very subject about a year before Honda came out with the original TL 250. So any old timers/trials historians out there to lead me in the right direction would be of great help.:D
    #5
  6. OneAUout

    OneAUout One AU out

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    Try Googling for this: Peter Gaunt and Alan Jeffries converted several XL Motorsport Enduros to trials. They changed the angle of the head, cut the bottom tube, put the engine higher in the frame and dropped the weight to around a little over a 100+ kg I believe.
    #6
  7. Thumpermeister

    Thumpermeister roost maker

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    TL's started out as XL conversions, however with any number of the former available these days it's hard to see the appeal of going through a whole bunch of trouble to end up with a trials bike still inferior to a TL?

    If you want a project, start with a TL and perhaps a Miller or Seely type kit frame to make a better trials bike then a stock TL! :thumb

    [​IMG]
    #7
  8. GarageRat

    GarageRat Been here awhile

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    This is an interesting idea. I have an old motosport worth experimenting with, a few DT1's as well. The DT may be a better prospect just based on weight, or lack of weight.
    #8
  9. PSchrauber

    PSchrauber Been here awhile

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    Just go ahead, it will be very interesting to see the result, the main problem will not be the engine as I understood.
    There you have a lot of knowledge. But the frame and the weight, this is the tricky part I think.

    Here a conversion with a 350ccm Husqvarna engine, just to see what is possible. The frame was made around the engine:

    [​IMG]

    [​IMG]

    Bike was still a little bit overpowerd.:lol3
    #9
  10. roninwva

    roninwva Been here awhile

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    I've been thinking about the same thing so keep us informed and show some pics of the progress. I think it would be as good as some of the old thumper trials bikes from years ago. Maybe a little twin shock, vintage, novice trials for fun.

    Check this out. I like it!
    http://www.twnclub.ch/classic_trial_files/honda_files/XL250/JeffriesXL250.htm

    Attached Files:

    #10
  11. roadholder

    roadholder Long timer

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    Neil Gaunt has done some interesting projects as well...even getting heavyweught pre-65 classic trials bikes down under that weight.

    http://www.classicdirtbike.co.uk/news/gaunt-ariel-classic-expert
    #11
  12. grizzzly

    grizzzly The Pre-Banned Version

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    the engine isn't the big problem its the suspension it sucked on those bikes.
    there were several people in our club (i think Bud Cole built most of them) took the engine out of a TL 250 and put it into a bull taco frame we called them hontaco's i was riding one before i got my first mono shock the 86 TY350
    try to find a copy of "how to ride Observed Trials just for fun!" by Carl Shipman, there is a section "how to improve your enduro bike for riding trials" (page 117)

    it is a great book
    another good book by the same guy
    [​IMG]
    #12
  13. plane_ben

    plane_ben Adventurer

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    Thank you gentlemen. That is exactly the info I'm looking for. I'm going to go aquire an XL250 tomarrow.:clap
    #13
  14. GarageRat

    GarageRat Been here awhile

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    Good luck Ben, I know I'll be watching!
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  15. plane_ben

    plane_ben Adventurer

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    Well, it was still there and I had a green light from the wife, just have to finish her CT90 first.:cry So here it is.

    [​IMG]

    [​IMG]
    #15
  16. Megamoto

    Megamoto Yes, I do look like this.

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    You know...I think I've been here before.
    Nice. Nice Dub also.
    #16
  17. Brunow - 007

    Brunow - 007 Bantam Fever

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    Sweet bike! i'm so subscribed to this one.
    Strip what you don't need & get her going!

    I bought an old honda cb125s base of a trails bike.

    A couple of things:
    -You need a soft clutch!
    -Easy to work on (clean & maintain)
    -Lightweight
    -Heigher ground clearance
    -low rake angle -> for those tight turns one observed trails! (WATCH OUT WITH HIGH SPEEDS!)
    -Low gearing! (i'm thinking of 2 different front sprockets one for cruising & 1 for trails)

    http://bikearama.com/theory/motorcycle-rake-trail-explained/

    :freaky:freaky
    #17
  18. roninwva

    roninwva Been here awhile

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    Looks good for a trials conversion. By the way is that an old VW pickup?
    #18
  19. plane_ben

    plane_ben Adventurer

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     By the way is that an old VW pickup?
    Yea. That's my shorty VW truck. Took four feet out of the middle. The XL barely fits in the bed.:D
    #19
  20. nevgriff64

    nevgriff64 ɹǝpun uʍop ɯoɹɟ buıppoɯ Super Moderator

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    I really like the look of this one.. :clap

    [​IMG]

    [​IMG]
    #20