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my VTR250cc back on the road

Discussion in 'New Riders and Riding Tips' at netrider.net.au started by Komunista, Sep 28, 2007.

  1. hey guys finally got around to getting my VTR 250 back on the road. The cosmetic mods i done are

    single seat look by adding a custom made cowl
    flat bar handlebar
    very tiny blinkers
    staintune pipe
    new tear drop mirrors
    new custom fender

    the mechanical mods that were done are

    bored out by 1ml ( which makes it technically a 400cc i think )
    changed pistons and carby accordingly
    re-jet

    pics of it are in the below links

    http://www.netrider.com/forum/download.php?id=15&mode=view

    http://www.netrider.com/forum/download.php?id=16&mode=view

    http://www.netrider.com/forum/download.php?id=17&mode=view

    http://www.netrider.com/forum/download.php?id=18&mode=view



    for anyone interested where i got any of the parts just ask me and i can point you in the right direction
     
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  2. AWESOME mate. 400cc? Thats a great looking bike!
     
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  3. yes because it has been bored out ... making the bore bigger.. making it no longer a 250cc .. and making it approx a 400cc
     
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  4. :rofl: :rofl: :rofl:

    no it acutally makes it around 257.64cc. 400cc, is that what they told you to justify the $1500 or so it would have taken to do that? you are still learner legal in victoria with that displacement

    V=3.14(given rounding for pie) x (r x r) x h / 1000
    the NT400 Bros, has a (bore/stroke) of 64x62 and that is 399cc. and it put out 34ps.

    nice looking bike though.
     
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  5. i work for a motorcycle company so it costed me nothing.. the guys in the work shop are actually race mechanics so they thought it would be fun to play around with my bikes engine.. benefits of working for a motorcycle company :) all the work basically costed me ( at cost ) for parts and for labour a case of beer :grin:
     
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  6. cowl looks good
     
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  7. Why bother boring it out by 1mm? Where the pistons rooted? Thought about turbo'ing it? Do the flat handle bars change the riding position by much?
     
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  8. oh fair enough, if a rebore only cost me a slab id do it too :LOL:
    have you got it dynod?
     
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  9. next up is put some superlows on it, stroke it to 355 and put a 2.5 catback on it and your laughin.
     
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  10. Bored it out because the guys in the work shop were just wanting to experiment

    The pistons were changed accordingly

    the flat handlebars change the handling alot in a very good way.. The turing circle aint as big but i can dip into corners much easier and the ride position is more aggressive... feels more controlled and responsive......
     
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  11. Nope dont have it dynod yet ... will do it soon tho... i will let u guys know the results... I actually raced a stock VTR 250 yesterday ( my mate's ) we had about 20 or so attemps ( straight line only ) about 1/4 mile.. and my VTR beat his everytime... even when we switched bikes my VTR always beat his... So i know for certain that the mods that were done to the engine has helped with the performance... It actually feels asif if has more top end speed :?

    ( and just to for all the do gooders we raced in a back street at about 10:00pm in an industrial area )
     
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  12. Yeah I agree with you, with the flatter handle bars your weight would be more over the front wheel like sports bikes.

    I would say the biggest increase you have is your race pipe which would give you a few more hp over your friends!
     
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  13. yeah as long as you keep the revs over 6k, pipe is good. my VTR250 will beat an XR400 in a straight line easy.

    yeah even with only 10cc extra, everything is relative, you would get a bit more torque

    ohh and just to add go up 3-4 teeth on the rear sprocket. makes a massive difference. how often do you need to go at $1.60 anyway?
     
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  14. adding 3 or 4 teeth will do what exactly ??? more bottom end or top end speed ?
     
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  15. bottom end quicker, lower top end speed, probably be able to wheelie much easier
     
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  16. mmm wheelies :grin:
     
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  17. yep mono easier it will. over a crest, changing up to fourth has lifted the front wheel up enough to keep me entertained. i can still pull better monos on the 250 than the thou
     
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  18. It will rev higher a 100 km/h though. With the sprocket change what will it rev at 100km/h and how much left is there until red line?
     
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  19. Looks hot mate. Wish I still had my license so i could see it in action, would be a sighth to see!

    Have you thaught about adding something like this
    Would make your bike almost unrecognisable to most and would make it look hotter imo. Maybe worth looking into what different fronts you could find.
     
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  20. i dunno about 4 teeth, but up 7 on the rear means rev limiter @ 103 in third, 122 in 4th and 148 in 5th. i dunno what it will rev at 100kms in top, but im guessing around 8 grand
     
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