Help Needed MTX125

[markie]

Can anyone help

I have a Honda MTX125 that keeps seizing.

It has done this three times. None of these times has it lost any fluids before stopping it just stops and the head seizes up.

First time it had the head opened and new piston and gaskets in but only ran for three hours. Second time there was no damage to anything inside they just seemed to swell and seize, Once opened taken out and replaced it worked again for two hours. Third time the head was completely redone but again oinly lasted a short time before stopping again. When you try to kick it over it will just not try. I am at my wits end. Any suggestions

markie

[TheShaggyDA]

Is any of the 2 stroke oil actually getting used? Might be the autolube, so premix it and see if that cures it.
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[cagiva gezzer]

Are you just putting new pistons in, or are you getting it honed/plated again?
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"because one stroke isnt enough and four strokes waste two"

[stinkwheel]

If you scrap it can I have the reed valve block for my H100

Finding out why it is seizing in the first place would seem to be a good place to start because they should be a good running little motor.

It is pretty much going to be down to one of the following:

1) Ragging it too hard.

2) Insufficient fuel being delivered due to eg. a blocked main jet.

3) Too much air being delivered due to an air leak, a busted air filter, botched 'tuning' attempts.

4) Insufficient 2-stroke oil due to a blocked/airlocked oil line, faulty pump or forgetting to put any in.

5) Too little back pressure (which causes lean running) due to a leaky/holy exhaust, race exhaust improperly set-up, botched 'tuning'.

6) Timing Way out if points ignition.

7) Something preventing heat dissipation from the cooling vanes such as a thick coat of paint, mud etc.
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I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Kickstart]

Hi

As above, but are you using Honda pistons or pattern ones?

My old MBX125 rarely lasted long enough to run a new pattern piston in, but was OK on Honda ones.

All the best

Keith
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