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J3NNINGS_024

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hey guys, at the start of the year i bought a "Dirtmax 150cc Avenger version 2" for my perimeter build. As soon as i got the engine in the bike i dropped the shipping oil and put in castrol activ 4t and did the valves. I ran it in hard and serviced it when it needed to. so as you can see the engine has had a good life . I only rode it for about 5-10 hours and it started to loose alot of compression. i did the valves and checked them like 5 times, then i gave up. i pulled the head off because my mates dad offerd to do some porting for me. so a month passed and he got back to me 2 days ago and he said its f****d. cam stuffed, valves stuffed valve seals stuffed. I took my cylinder and piston off and its stuffed, the piston skirts are scuffed and the cylinder is scratched up. So pretty much the whole top end has destroyed itself after 5-10 hours. Shite head design by dirtmax:mad:. it doesnt even have the updated center cases. ive thrown up a few pics of the cam and piston. (sorry couldnt resize pics guys)

as you can see the cam lobes are scratched or "gouged"
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piston is scuffed
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Never buying dirtmax again:flipa:
 

no_crf50_here

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IMO - piston is normal and still very much useable (typically those scuff marks are from over reving in my experience), same for the cam wear marks but nothing that'll stop it from being rideable.
 

thump*140

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Hmm, that's slightly embarrassing, Dirtmax have a heaps good name on here...
 

TyD

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Dirtmax don't design motors, they just import them with their logo like every other company... So sorry, but you fail.
 

sean01

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unfortuneatley it doesnt look like a dirtmax fault, wish i could say other wise cause there a bloody AWESOME brand...lol... (bill you suck)..

anyways, well the cam looks like it has been cooked( ran too hot) or run dry from oil.. its rooted.. you can see the wear lip on the edges of the cam and it looks like it has lost alot of lift..
but dont stress and you can replace the cam and the seals... maybe a good opportunity to buy something better.

did you have an oil cooler fitted to this and if so can you explain where you connected it?

pistons scuff if you dont use a high quality and well serviced air cleaner or again if the engine has an oil problem or cooked..

only thing i can confirm is that the valve guides and seals are the only fault in these heads, the guides stick up too far for the camshafts valve lift.
everything else seems like a maintenance/servicing/accessory fitting fault..

oh and apparently dirtmax (australia) are spose to have some sort of connection to some of the design of their engine/parts.. true or false? couldnt tell ya
 

thump*140

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either way, it's still an Epic Fail, ANY engine should last more than 10 hours.....
 

sean01

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well that is true but if it caused from an oil issue from day dot then i think 10hrs is a miracle..
 

J3NNINGS_024

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unfortuneatley it doesnt look like a dirtmax fault, wish i could say other wise cause there a bloody AWESOME brand...lol... (bill you suck)..

anyways, well the cam looks like it has been cooked( ran too hot) or run dry from oil.. its rooted.. you can see the wear lip on the edges of the cam and it looks like it has lost alot of lift..
but dont stress and you can replace the cam and the seals... maybe a good opportunity to buy something better.

did you have an oil cooler fitted to this and if so can you explain where you connected it?

pistons scuff if you dont use a high quality and well serviced air cleaner or again if the engine has an oil problem or cooked..

only thing i can confirm is that the valve guides and seals are the only fault in these heads, the guides stick up too far for the camshafts valve lift.
everything else seems like a maintenance/servicing/accessory fitting fault..

oh and apparently dirtmax (australia) are spose to have some sort of connection to some of the design of their engine/parts.. true or false? couldnt tell ya
yeap, its always had an oil cooler and filter. im buying z160 anyways as the 150 had crap torque.
 

sean01

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yeah cooked oil or overheating is the most common cause..

and WAT the dirtmax 150 had crap torque.. but here ment to have a whopping 16hp...bahahhahaaa
 

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