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Dt125r broken rings ;(


kenDAWG
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Well got the cylinder and head off her!!

Doesn't look nice.

First glance the head looked fine apart from small dents all over the detention surface.

Then the cylinder didn't have any obvious marks or chunks missing but the piston had 1/4 of a ring missing and a few bits lying in bottom end!

Also the small end baring where stuff as hell, I had to get a pin and hammer to knock out pin.

I've test fitted a new piston and I find when I push in the piston there is resistance at the top of exhaust port so I'm guessing that's not good.

Would it be worth getting the dremel out and tryin to smooth over the edge of exhaust port?

Cheers

Ken

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Do you think I could get away with a quick stint on my trusty dremel??

I'm a little gutted as I wanted it sold soonish there's a nice honda ns125 I wouldn't mind taking a look at, comes with a full spare bike (same model just needs painted up and clutch looking at for both for £1.2k)

Ken

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What do you think parts of a ring could do if they have getting into bottom end?

Is it worth getting a magnetic sump plug??

To say I'm fucking gutted is an understatement, also the bolts with the hole in middle used for the heating pipes from head to carb I've snapped one.

Any ideas where to look for one?

Cheers

Ken

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shit ken, a sump plug is nothing to do with it mate, on a 2 stroke the crankcase is a sealed chamber and is nothing to do with the gearbox.

The only sure way is a complete engine strip

There may be alternatives but not as guaranteed as the complete strip down, sorry mate I know it's not what you want to hear but there it is!

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You could hope the bits of ring are in the exhaust Ken but I very much doubt it, plus I have a bolt for the head if it will help you out, pm me

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shit ken, a sump plug is nothing to do with it mate, on a 2 stroke the crankcase is a sealed chamber and is nothing to do with the gearbox.

The only sure way is a complete engine strip

There may be alternatives but not as guaranteed as the complete strip down, sorry mate I know it's not what you want to hear but there it is!

I really don't have time for an engine strip I think I might have to sell her on with problem.

Working 12hrs a day and also DIY in house on weekend.....

Bloody hell-my reliable dt has let me down :(

(Pm sent to nev)

Cheers

Ken

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Rings are much harder so shatter with sharp edges so honestly i think its done the crank seals.

An old dt125mx engine i bought ran without a bottom ring.

On the pluss side. Set of rings. Crank bearings seals and a gaslet set will only be 70quid tops. You will lose more selling it busted. Only take a day.

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They already have. It wont start so the bits of ring have prob done their damage.

The popping you mentioned before indicates an air leak. Like i said it should still run fine with just the top ring. Less power obviously but it should run.

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Nah the other ring was cracked so its not creating a seal with cylinder!!!

One if the rings has gone and nicked exhaust port and that has prob taken out the second ring....

I'm surprised there isn't any scoring or gouges on cylinder liner but there is nothing apart from the nick.

Cheers

Ken

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Maybe all in the exhaust rinse ot out with pertol and see what bits you get.

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