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Discussion Starter #1
i have a 91 phazer, its .40 over ,ported, piped, jets are right. b4 i tear my whole motor apart to check timing and lose trail time, is it possible for a 2 stroke to ping? or would this be some type of rod knock... or clutch. clutch has new rollers.

its seems to only do this pinging once it warms up, and only does it when its around 70-80 mph, wide open, and its maxxed out. alot quieter and faster after i let it cool. i run 93 gas, and it didnt do this b4 the crank seals and porting. it used to get up around 100 mph.
 

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Discussion Starter #2
so i tore it down again to check timing, it was actually retarded. so i advanced it. i had the wrong plugs. b9es (thanks autozone) , put br9es and some octane booster, my ping went away but i still cant get over 80mph.

anyone think a worn out reed could cause this? i have boysen reeds....
 

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garage port? or was it someone whom has had luck with that motor? clutches aligned properly?
 

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Discussion Starter #4
i didnt port the skirts but i opened and raised the intake, then i hogged and polished the exhaust. actually made a differance. it was a kitchen port job in my old apartment......

i took my secondary off and saw it was rubbing on the jack shaft. so i definatly have a alignment issue, and im guessing thats my ping noise cuz it came back. was wondering if i could take the shims out of the front of the sheave and put them in the back where its rubbing?
 

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so i tore it down again to check timing, it was actually retarded. so i advanced it. i had the wrong plugs. b9es (thanks autozone) , put br9es and some octane booster, my ping went away but i still cant get over 80mph.

anyone think a worn out reed could cause this? i have boysen reeds....[/b]
Seems to me that with a fan cooled 480cc engine you're lucky to hit 80. Maybe I'm wrong. I know my EXT Special didn't do over 80 and it's a liquid 530. Gearing is a factor, but I find it hard to believe that engine could pull much more than that even in really fast snow.
 

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Discussion Starter #6
you would be suprised, im pretty sure i could beat your vmax if its stock. ide be happy try at least. the reason im posting this is because it use to go 100 and doesnt now. not bad for 500 bucks
 

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there are chances you lost hp with the port job, just as well as gained. you may have seen 100 on the speedo but in reality it was never close to that. get the clutches aligned and let us know what happens.
 

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Discussion Starter #8
well then, i guess i should rephrase this post. my sled used to register 100mph on the speedometer, but now it only registers 80....... :withstupid: gimme a break,
 

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Discussion Starter #10
i got it shimmed right now, still pings, same problem. i did a compression test i got 150 psi each cyl. just seems like its not shifting. gets up to 7000 and thats it. it gets there quick. if i run it on a stand, it will get up over 8000, and i dont hear any noises. just when its got a load.
 

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i got it shimmed right now, still pings, same problem. i did a compression test i got 150 psi each cyl. just seems like its not shifting. gets up to 7000 and thats it. it gets there quick. if i run it on a stand, it will get up over 8000, and i dont hear any noises. just when its got a load.[/b]
I think you should now work on your fuel input.I agree with dooman about the relation to the port job.You have to match up your port job now with a richer air intake or you are going backwards.
Whatever size carb /or intake you are using,you should now increase the intake(air) and maybe even hotter spark.Whenever the passages are increased for airflow if the intake is not increased one would expect a vaccum and a loss of top end.Just a thought.
 
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