Piston Slap On TS1?
Posted: Thu Nov 12, 2009 10:30 pm
Has anyone experienced this with TS1 225, 58mm AF crank and Racetour piston? 
Can I ask what the symptom of piston slap is, is it a noise issue?
I often hear of the term.
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Piston Slap On TS1?
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Re: Piston Slap On TS1?
Posted: Fri Nov 13, 2009 1:34 am
Re: Piston Slap On TS1?
Posted: Fri Nov 13, 2009 8:08 am
The reason I ask is that when turning the flywheel by hand a slight knocking can be heard from the cylinder whilst rocking it back and forth around the TDC area. Piston slap, or something else???
Re: Piston Slap On TS1?
Posted: Fri Nov 13, 2009 1:45 pm
hello there
you will find the noise you are hearing is from the big end or small end bearing on the rod
if you have any play in the drive side or mag bearing or on the crank or pin this can also course this noise when you rock the flywheel back and forth
the only way to tell is to strip the top end down and carry out all your checks you will soon find the problem
when you pick up a old crank and give it a wack you can hear the noise
all the best
you will find the noise you are hearing is from the big end or small end bearing on the rod
if you have any play in the drive side or mag bearing or on the crank or pin this can also course this noise when you rock the flywheel back and forth
the only way to tell is to strip the top end down and carry out all your checks you will soon find the problem
when you pick up a old crank and give it a wack you can hear the noise
all the best
Re: Piston Slap On TS1?
Posted: Fri Nov 13, 2009 1:50 pm
also.....if there's a knocking noise by hand then have another look matey before you run it. Make sure piston is not hitting head. Has the ex port been excessively widened? If you are using a head gasket make sure its not touching the piston.
Re: Piston Slap On TS1?
Posted: Fri Nov 13, 2009 2:30 pm
the noise can sometimes be due to excessive piston to bore clearance, which allows the piston to "rock" on the rings at tdc.
This can be quite common, and diminishes/ goes altogether when the engine warms up.
You can sometimes feel it by hand if you whip off the downpipe, and place a finger thru the exhaust port on the piston at tdc and move the flywheel back and forwards around that point.
I always try to run with the minimum piston to bore clearance but it is a trade off to noise vs the possibility of seizing!
Chris
This can be quite common, and diminishes/ goes altogether when the engine warms up.
You can sometimes feel it by hand if you whip off the downpipe, and place a finger thru the exhaust port on the piston at tdc and move the flywheel back and forwards around that point.
I always try to run with the minimum piston to bore clearance but it is a trade off to noise vs the possibility of seizing!
Chris
Re: Piston Slap On TS1?
Posted: Fri Nov 13, 2009 2:34 pm
tony wrote:If you are using a head gasket make sure its not touching the piston.
That's when it started, when I fitted a head gasket (against my preference but needs must) my money's on that 
Cheers chaps
Top on, top off
Re: Piston Slap On TS1?
Posted: Fri Nov 13, 2009 3:45 pm
what is your squish, you can run without a head gasget 
but you must make sure the head and barrel are flat and use lock tight on the face but not much
i ran a ts1 for two years without a head gasget ,but i used a mbd forged head to stop any warping and the the barrel was not doweld
but you must make sure the head and barrel are flat and use lock tight on the face but not muchi ran a ts1 for two years without a head gasget ,but i used a mbd forged head to stop any warping and the the barrel was not doweld