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  • blackbart
    replied
    Anyone got hookups for cheapish dirt bike mechanical shops in Syd? 05 WR250 needs the valves replaced/head service, and fork seals.

    Leave a comment:


  • turbo510
    replied
    I would be contacting the people who replated the cylinder originally.

    That will require a full rebuild to make sure there are no parts of the cylinder coating in the crankcase.

    Hope it isn't too hard a fix.



    Leave a comment:


  • Greg Rust
    replied
    The area of the piston above the ring land looks odd. Got a close up of that now the piston is out?

    Leave a comment:


  • Grungle
    replied
    Yeah, they've quoted $600 and a few days turnaround. Another place says $520 and 3-4 weeks, so I assume they send it to the US.

    I just want to know why it happened after just 10 hours and if there's something I can do to stop it happening again.

    I don't think it overheated, as it had coolant. I didn't measure it, but it seemed about right.

    Leave a comment:


  • buket of water
    replied
    looks like the cylinder needs re-plating.

    I use these guys for my bikes
    https://www.electrosil.com.au

    Leave a comment:


  • no13b_Coupe
    replied
    Originally posted by CA18escort View Post
    Forma make adventure boots that look nice. I would never use them on a dirt bike. I run SIDI boots, crossfire on the WR450 and gortex adventure for normal riding.
    Yeah lol. That's about it. I'd probably use them to ride my dirt bike to work maybe. They are comfy as fuck but.
    I'll have a look at those as well.

    Leave a comment:


  • fnlow
    replied
    I'm not heaps familiar with the 500. any signs of coolant leaking into the bore via head or base gasket? i would have expected to see more carbon on the top of the piston unless it has been getting a good wash and leaned out when out of coolant. have you measured the amount of coolant when pulling it down?

    Leave a comment:


  • Grungle
    replied
    Fuck.
    So you know that KX500 I was considering selling a few posts back? I had someone come and have a look at it. He knew bikes and 500s, so he was keen to start it. He kicked it for a few minutes and couldn't find the right spot, so I jumped on and had it going in 2 kicks.
    It ran for about 30 seconds and then abruptly shut off. We played around with it for 20 minutes, more fuel, checked the carb, cleaned the plug etc, but no go. It also seemed down on compression compared to when it first started. Hmmm. We gave up, he said to give him a call if it can get it going, and I pushed it back in to the shed.
    It bugged me all night. It's a reconditioned cylinder (with new nikasil plating), new piston etc. Has run without a problem for about 10 hours, and now it won't go.

    So I did a compression test. 50psi. Fuck.
    Pulled the head and found this:
    Click image for larger version

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ID:	7107570 that doesn't look good.

    Pulled the whole lot and:
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    So I've hit up some places to see if it can be fixed, but what happened? The rest of the cylinder is fine and the top of the piston looks fine (to me) apart from all the flakes of destroyed liner getting pounded into the rings. It's both sides - intake and exhaust.

    It kind of looks like it failed around the ports and spread from there. It wasn't ported, and the liner appears to 'wrap' around the ports. I assume I would have oriented and gapped the rings correctly, but I haven't checked that yet. The piston is in the right way - arrow towards the exhaust. It never seized and I don't think it overheated. Dodgy liner? It cost about $600 from memory, and was done through a Kawasaki shop. A problem with the bottom end? I've never touched that, but the bottom ends of KX500 are supposedly bulletproof, and I don't think this one had been used much. Shit fuel? Wouldn't that show up on the top of the piston?

    I haven't done a lot with 2 strokes, so has anyone got any ideas? I would prefer for it to not happen again.
    Attached Files

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  • buket of water
    replied
    I broke my femur in fox instinct boots.

    I would recommend them. Had no issues with anything else ... just the femur

    Leave a comment:


  • CA18escort
    replied
    Forma make adventure boots that look nice. I would never use them on a dirt bike. I run SIDI boots, crossfire on the WR450 and gortex adventure for normal riding.

    Leave a comment:


  • no13b_Coupe
    replied
    My father in law bought FORMA branded boots.
    One ride in and he broke his ankle. I got given them to use. The sole wore away from kicking my bike over (perfectly in line with the kicker) and that's me assuming what it was.

    I'll buy some tech 7s after reading the above.

    Leave a comment:


  • darkside
    replied
    Yeah,

    it’s moments like that you learn nothing short of a proper motorcross boot will do for off road riding. Wont be the last time you get belted around the foot/ankle/shin. Recently upgraded all my gear and landed on the tech 7. Really rate them.

    Leave a comment:


  • Greg Rust
    replied
    Was out on a trail ride with some dudes. Had the SX pegged in 3rd up a rocky fire trail. Took the apex and didn’t see a fallen tree that had been sawn off poking into the trail. Hit my boot smack on just above the ankle which flung my leg off the peg.
    expected to look down and see my leg broken, had a few minutes on the ground before riding on.
    thanks to Tech 7 boots for saving me.

    Leave a comment:


  • Greg Rust
    replied
    Sweet, will check the Legion range

    Leave a comment:


  • Beavis
    replied
    Klim is pretty good but the price is high.

    I've used MX gear in the woods, but unless it's top dollar stuff it just disintegrates when you hit something.

    Leave a comment:

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