9 replies to this topic

[Craig89]

Hello all. I'm about ready to send my 1275 engine components off to be machined but the crank damper is giving me a head ache.

The one removed from the donor engine was in a pretty poor state (perished rubber etc) So I sourced a spare but its mass is notacibly larger, it's outside face is about 6mm deeper.

The one removed from the engine, part no. TAM2011, weighs 1.3kg

The other one, part number CAM4902, weighs 1.55kg.

If anybody can offer up some advice on the
subject I would much appreciate it.

Thanks, Craig

Attached Files

•  IMAG0997.jpg   34.89K   25 downloads
•  IMAG0998.jpg   40.94K   26 downloads

[cal844]

Cant you just get the heavy one faced(lightened) to the right weight?

[Craig89]

Cant you just get the heavy one faced(lightened) to the right weight?

I did think of that but I first wanted to make sure that the one that came off the engine is the correct one as it looks very similar to the one currently fitted to my 998.

I do also believe that they're weight effects there damping across the rev range?

[Craig89]

Bump

[cal844]

Cant you just get the heavy one faced(lightened) to the right weight?

I did think of that but I first wanted to make sure that the one that came off the engine is the correct one as it looks very similar to the one currently fitted to my 998.
I do also believe that they're weight effects there damping across the rev range?

Id imagine it would affect the damping

[benjy_18]

AFAIK the smaller of the two were fitted to small bore engines (998 etc) and the larger dampers were fitted to 1275's

Edited by benjy_18, 06 October 2014 - 08:47 PM.

[Craig89]

That sounds logical. Can anyone confirm this?

Cheers

[KernowCooper]

Yes the heavier one was for the 1275 engine to combat a harmonic between around 5800-6200rpm, the 998 engine doesn't suffer from this though and used a lighter damper

[s3swiss]

"a harmonic between around 5800-6200rpm" - yikes!

My ears are bleeding when my 998 get to those rpms - wouldn't be worried about a vibration - more the rods making a break for it!   

[Craig89]

Yes the heavier one was for the 1275 engine to combat a harmonic between around 5800-6200rpm, the 998 engine doesn't suffer from this though and used a lighter damper

Thats great thanks, puts my mind at rest now