engine noise on my Z

[twgranger]

On my 85 Z when i am putting around i will hear a knocking noise from my engine but when i hammer on it and when it is ideling it does not make that sound. Is it normal or is something going bad????

[YTZ250#1]

What kind of motor mods are done?Could it be a spark knock from not having high enough octane fuel?

[twgranger]

What kind of motor mods are done?Could it be a spark knock from not having high enough octane fuel?Nothing special. Dg exhaust and reeds and a mild port job. Should i try some octane booster that they sell for cars???

[03 ORANGE SHEE]

not to burst your bubble,but mine did that same thing,and two rides later that lower crank bearing broke and through all those pieces into the cylinder and tore up the bottom off the head,$293 dollars later its running fine now!!

[TimSr]

How many hours are on your bore? Sounds like the infamous low end piston slap. As long as youve got good compression, I wouldnt worry about it, but when your rings wear and compression drops, your looking at a bore instead of a ring change. Im in the same boat. Mine needed bored but I needed it for Trikefest. Ill get by all season before getting it bored now.

[twgranger]

There is not many hours on the bore. I had it done during winter and never started riding it entill spring but not that much. So you think my crank bearings are bad??

[twgranger]

I just dropped it off at my machanics so i guess ill wait and see what he says is making that noise. :(