DT230 2 piece power valve?

[marks]

the DT has been running like shite and rattling at the front of the engine.

The power valve has snapped right through the middle - hopefully I can get a new one but should I be looking for a cause or just throwing the new bits in??

[Motu]

I guess the thin part is a weak spot,but there isn't a lot of load on it to cause a break.I'd look to tightness or wear in the bushes...the only lube they get is the thick puss coming out the exhaust.I used to get a drop of black puss on my boot sometimes because of a worn seal,which is common on this type of Yamaha power valves.Maybe some sort of maintenance program....clean and lube.Still less work than doing the valves on a 4 stroke.

[tri boy]

Check for slop in the housing/cyl/bearing surfaces.
Normally, only excess bearing/bush clearance allows for fracture type vibration.
Also check actuator condition, and excess build up of carbon in exhaust port that could of added turning resistance.


That will be $300 consult fee.
Please pay before end of oct, or pay for all my drinks on your trailer trash ride.
(oh yes sunshine, I plan on crashing the party)

[tri boy]

I used to get a drop of black puss on my boot sometimes because of a worn ........

I'd see a specialist about that.
Does it burn when you pee?

[marks]

That will be $300 consult fee.
Please pay before end of oct, or pay for all my drinks on your trailer trash ride.
(oh yes sunshine, I plan on crashing the party)

the $300 will be cheaper than paying for your drinks....



thanks guys for the responses

everything (bushes etc) appeared good and the break looked old - it had all worn very smooth at the break point

I'll get a new valve (hopefully I won't have to wait for ages) and see if its all good.

[XF650]

Remember to wear rubbers Mark - you don't want to catch what Motu's got.

[marks]

Remember to wear rubbers Mark - you don't want to catch what Motu's got.

the dreaded black puss