Hey guys... I need some help here... yesterday I was driving my bike 1990 XT600E at 50mph and suddenly it went dead, the engine stopped running, it just turned off... so I stopped on the side of the road and tried kickstarting and felt no compression... by guess is that the piston rings went kaput... I won´t be able to fix it until I get back home in a couple of months but my best guess is that I'll need to bore the cylinder and order a piston kit..

I'm thinking of buying a Wiseco piston but until I go back home I just can´t know the extension of the damage and can't order the piston kit and gaskets...

I think this happened because last time I came here I left the bike without the cover of the left side of the engine due to not being able to push the kickstart stopper into the little hole it is supposed to go into... I know I know I'm an idiot.


Or could it be anything else? valve timing?



I only kicked it twice slowly just to try 'n finding TDC...

The last time something similar happened to me it was the spark plug that stripped its' thread and flew through the night air like a glowing meteorite!

But, I guess if that had happened you would notice it just as much as I did, so maybe it is the valves!

Good luck in the fault finding,

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Dave

I used to own a KX 250 MX bike that did the exact same thing. Very dodgy indeed,I once almost took my mate out with a sniper shot riding through some fields at about 50mph,The noise when that thing poped out was very disturbing to say the least.

Sorry to hear about your problems bacardi,Check the plugs screwed in properly for sure,Is it the right plug for the bike (Heat range).Ive heard of wrong type plugs warping/burning holes in pistons etc.Hopefully it's something much simpler to fix.~(Im sure it will be).

Good luck.

Darren

just to start with easy things, you say xt600e and then kickstarter, is it a modded thing? Check if you have any problem with decompressor cable, maybe disconnect it the cable, and then check the spark plug as said. For the spark plug, if it's stripped, a good service can use an helicoil or timesert (better) to fix it.

Hi. darren_m The plug is the NGK DPR8EA-9 just like the one listed on the manual that I am sure off cause I'm the one who put it there =P

cyberzar xt600e and then kickstarter, is it a modded thing? Yes I fitted it but I didn't put any of the decompression parts, just plain old leg power

I'll have to tell my brother to take the plug off to check it....

BTW, what is helicoil or timesert?? I do have a thing to check the compression in the cylinder that looks like a sparkplug and fits like one in the sparkplug hole but I would have to kick the bike but it might damage the cylinder sleeve if any of the rings did break...

If you got anymore ideas, let me know

Thank you all =)

There are so many things but as you say you were traveling at 50 and it cut out theni would say that its not going to be a valve problem as it shold have still run but badly but doubt it would restart. but still worth a try check valve gaps see if any have got really slack valve could have got stuck or seat moved. one quick try for a ring problem isremove plug squirt some oil in the cylinder (not too much just to seal). replace the plug and see if its ant harder to kick over. Hope its something silly and you get it sorted

They are both methods of repairing damaged threads, based on replacing the thread with another one of the same nominal diameter; search on the internet if you want to know more about them - they come as a kit if you are going to do a few of them, but workshops can do an individual one for you.

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Dave

Ohhh.. Just took me a few seconds to find out what they are and which one is better lol.... I already new what they were but just didn't "see" it by those names If it is this problem, I'll fix it with a Timesert which is much stronger

Thanks

Hey guys. I ain't gonna need that timesert nor the helicoil because the sparkplug is where it is firmly in the sparkplug hole.. if my brother wasn't so damn lazy I'd be knowing already what the bike needs.. I'm gonna keep with the piston theory because it's the most likely..

One question, do you think I should change the bearings of it.. the bike only has a little under 11000miles but she is a 1990 model and has never been "in surgery" besides once (see thread comment #1)

Thanks

For my 2 cents worth, sort out what is the current problem before looking for more! (See above).
Check things logically, adjusting one thing at a time, if it is necessary, to see what difference that makes.

Bearings:
11000 miles is not much, if it is genuine??! And which bearings anyway? - a rebore is much less work than getting into the crankcases.

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Dave

Yes, the bike and the kickstart parts are Yamaha genuine.. all the bearings.. because they could've rusted? the engine, right side cover, was open for almost two months :\ tho always inside my garage and the weather was dry.... I will probably have to put an oversized piston on the bike,the smallest possible...but untill I get back home..maybe 1st February or just in beginning of March.. and I'll check everything maybe I'm just being paranoid about the bearings lol =)