GPX 250 running rough as all hell

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GPX 250 running rough as all hell

Postby Matt » Sat Apr 07, 2012 1:53 am

Hi guys, firstly just want to introduce myself, i'm Matt and i've been meaning to join the forum for a long time now and recently got a kick in the pants as to why.

Here's my dilema.

I own a GPX250. It was running fine. Had an ass back into it in a carpark, got it repaired and the mechanic cleaned out the tensioner, had the thing running beautifully.

Until the other day. Was sitting at the lights on Wallgrove road and as the revs dropped just under 2k got a really clunky sound coming from the engine. It stopped shortly there after and didn't think much more of it.

Then tonight happened.

Was riding home from the missuses house and the bike started running horribly. Started out as an annoying pitched whirring sound and developed into a much meater thudding along with the evil little red oil light coming on. Pulled into a servo, grabbed some oil and fed the bike all after checking the oil indicator window which showed me very precious little oil after sittingfor twenty or so minutes. Got back on and headed off.

The noises got a bit worse, engine temp redlined and throttle was unresponsive and stalled out when i pulled over. Then i noticed oil leaking from my air box. Eventually limped home, did an oil change and now she's running just as rough and still stalls out if she starts.

I'm hoping that someone here has some advice seeing as its anlong weekend and the mechanics are all probably closes til tuesday and my baby is my only form of transport.

Thanks,

Matt.
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Re: GPX 250 running rough as all hell

Postby GPZ_Jim » Sat Apr 07, 2012 3:21 pm

Does sound bad :( probably unlikely you'll get it going fine over the next cpl days.. Any signs of oil oozing out of the engine? Good news is that the twofiddys are very common and shouldn't be hard to either get another donk or another bike to yoink one from :) keep in mind the engine is unchanged all the way from the 80s so any gpx or zzr or even the ninja 250s engine will be a straight swap :)
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GPX 250 running rough as all hell

Postby Blurr » Sat Apr 07, 2012 4:25 pm

Did you loose power?
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Re: GPX 250 running rough as all hell

Postby dickfaber » Sat Apr 07, 2012 5:26 pm

I am a bilingual illiterate; i can't read or write in two different languages
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Re: GPX 250 running rough as all hell

Postby Gosling1 » Sat Apr 07, 2012 7:33 pm

sounds to me like the camchain tensioner has failed and the camchain may have jumped a tooth or 2 on the cam sprockets.

Don't start the motor again until you pull the cam-cover off and check the cam timing. If you can't do this you need to get the bike to a bike mechanic ASAP. Problems like this need more than a change of oil.

8)
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Re: GPX 250 running rough as all hell

Postby Matt » Sun Apr 08, 2012 12:03 am

Hey guys,

@jim: on closer inspection of the engine block there did appear to be a bit of oil leaking from a connector on the engine block, right hand side facing along the bike, a few inches from the rocker cover and a very small amount from the rocker cover itself. What would the process with dropping a new engine in? Mainly in regard to camchain adjustment, carbie sync, etc?

@blur: if you meant power as in electrical, no i didn't. Engine is another story, she seemed sluggish and slow to respond and stalled out if i let the revs drop too low. Seemed hesitant to start without cranking the throttle a little.

@dick: thanks for the link mate, saved in ebay watch list and i picked up a headlight mounting bracket from the seller (Bike Parts Sydney) in the past which i was guaranteed was straight, low and behold it was so i'm inclined to think they're trustworthy. Pdf of manual now downloaded and printed :)

@gosling: yeah i have held the desire to keep trying to start her at bay and have avoided trying to sort it out myself, oil changes, spark plugs, etc i can handle. Loud scary engine noises i know i'm out of my depth. Apart from a slight disassemble in an attempt to clean her up a bit i'm leaving it all for the mechanics. While i love tinkering i figured this was well out of my league.

Thanks to all of you, the advice is greatly appreciated so now it's the waiting game til tuesday when i can hopefully organise to have her looked at. Cautiously optomistic that its something a little less intimidating than a munted engine but i'll take it as it comes. And it just had to happen two months out from being able to upgrade to a full licence and a ZX7, bah!
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Re: GPX 250 running rough as all hell

Postby Matt » Fri Apr 13, 2012 1:12 pm

Well guys i'm back again, just thought i'd give you all a quick update of what the story currently.

Sent the old girl off to the guys down at the Bikesmith Blacktown, as per usual they were excellent, had the bike down there the day i called and heard from them this morning even though they had a fairly large back log of work and a couple of mechanics off on holidays.

After my initial conversation with John who was inclined to agree with Gosling the news got a tad worse. Turns out the big end bearings are stuffed. Not the news i was hoping for but still, i suppose it could have been much much worse.

So now the hunt is on, have sourced a number of replacement engines but the best price i have found thus far has been for $700 including a swap of my engine for the one that the wrecker has. Only 10 000 more k's on it than the current engine but in the instance that i am able to upgrade my license in roughly 2 months i'm not going to whinge too much.

Also took a look over the manual to check out the process for removal and installation of the engine and the process is a hell of a lot less daunting than i originally thought. So, once i get this weekend's work shifts out of the way the swap can begin.

I'd just like to say once again thank you to all of you for the advice, links and willingness to help out a fellow rider, i appreciate the help a great deal. If anyone has any extra advice that i may need in regard to the engine swap by all means chime in, it always helps to have a little extra knowledge. Overall whilst this experience isn't one i'd really like to be dealing with in my current situation (had a charming chat the other night with the bloke who damaged the front end of my bike a few months back who is STILL refusing to fork out money to cover the costs i paid for repairs) it is an interesting learning experience and is fueling my interest in picking up a mechanical apprenticeship.

Thanks,

Matt
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