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RS125-effects of highway abuse

Discussion in 'Technical and Troubleshooting Torque' started by loki, Dec 26, 2009.

  1. Hi all.
    This is a bit of a comeback for me, I've taken a bit of a hiatus from Netrider as it's painful to talk about bikes whilst enduring half a year of public transport.

    Last Autumn, I destroyed the engine of my RS125 in a story I like to call "How Can It Possibly Over-Heat When I'm Riding Through Heavy 2am Fog". In a nutshell, Aprilia's "GP Engineering" doesn't extend to 15 minutes of redlining down a highway. Which is fair enough, I was warned by a company rep. not to take it onto motorways, advice I chose not to follow on the night. While I was lucky enough to find a slightly-used crankcase from Germany's eBay for $250 (local wreckers were charging $2,000), this has still been a costly excercise for me with labour costs and electrosilling setting me back $1600. Which is a stupid amount of money to spend on a silly little 125, I agree.

    But after much patience, and several 'relaxing' drives in some more hired sportscars, my prayers to God (which consisted mostly of tearful promises to stop desecrating his Churches, and blackmail attempts concerning THOSE photos) were finally answered, and Santa gave me my bike back for Christmas, as well as a rider training course off my folks and a GoPro helmet-cam off my dear girlfriend.

    I'm planning on turning the old Rotax lump into some kind of bedside lamp or coffee table, but in the meantime I've taken some snaps showing the internal damage


    Amazing to be back on the road :)
    I've missed riding terribly. Hoping to meet-up for a couple NR rides over Summer, I have to wear the new engine in so the license is momentarily safe.
    Till then...
  2. Damn evil two strokes...Sell it as soon as you can and buy a 4 stroke before it does it again. Welcome back.
  3. Yup, those 4 strokes, they're indestructible they are!



  4. Cheers, Phil.
    Trying to avoid the often-regretted decision of selling that cherished first bike.
    As some of you may remember, I was assaulted last Christmas before citizen-arresting some shoplifters. Meeting with my blood-sucking lawyers after the Christmas break concerning a compensation case, buying me a new bike is the least he could do after rudely splitting my lip with a cheap punch.

    oh, I like a challenge ;)
  5. Mmm, both valid points of course. OK, keep the 125cc for old times sake and roll it out every now and then and rev it as much as you dare. But buy something that's not like hand grenade with a loose pin to ride all the time. Problem solved.
  6. Hmm, that piston looks similar to one that I pulled out of my RD350A the day after my last ride on it.... damn external oiling lines...
  7. That does look like a nasty 4 point seizure. When you get everything rebuilt, make sure you check your 2T pump settings.

    You didn't trust Mitaka enough to get one of their top end kits? They seem to be reasonable on the Aprilia, but shocking on the Cagiva.
  8. Thanks, definately be double checking the pump today

    Had a Mitaka on previously, it gave up the ghost :(
  9. Oooh! You'll be needing the bastard file on that ;).
  10. So this one was genuine Aprilia barrel and piston?

    What was your mitaka setup (barrel and piston or piston only) and what happened to it last time? I'm interested to know how good/bad they really are.
  11. not too sure how it died last time, it did get a few highway miles on it though which wouldn't have helped it. riding from Penrith to Botony for work, and it died on me as I reached Mascot... Think it was the standard barrel with the Mitaka piston. No way I'm going back to genuine Aprilia, I want to ride my bike NOW not in 4 months time when they've finished making some spare parts and shipped it out. New piston was through PJ Engineering in the UK
  12. Welcome back loki, and yeah...that damage looks pretty crazy! My brothers piston and bore destruction was bad but this takes the cake. He was ripping up the freeway past redline when it happened, on dodgy rings no less.

    As far as Mitaka piston kits go, I've done a few thou on mine and it seems to be fine - even as the original cylinder reaches an unmolested 30,000km. Anyway hope the PJ stuff does the job and you're back on the road soon.

    Out of curiosity, what oil/fuel combo do you run? I'm partial to Caltex 98 and Valvoline '2T Racing Oil' myself.

    Cheers - boingk
  13. hmmm, it sounds like the mitaka pistons are out of tolerance relative to an Aprilia bore.

    Interesting. I will one day (if I get the bike registered) try a Mitaka barrel and piston and see what the life is like in that setup.
  14. premium 98ron and Motul 710 is the standard...
    going okay so far. hoping it lasts out the summer :)
  15. just stay away from long boring highways :p