Cam belt Tension
 

Hi there. Just setting the tension on my new belts on the 620ie. I'm using the Allen key method. 5 mm for the horizontal and the same for the vertical. I've heard people using 6 mm instead. What's the path of the righteous?!

As the rear usually runs hotter they recommend setting the Vertical cylinder belt tension with a little less tension than the Front Horizontal cylinder.
I set the Vertical 15Hz less than the Horizontal

The point of using 6mm on the vertical is because it gets less airflow than the horizontal and runs hotter. This means it expands more, so the "running tension" will be greater than the horiz cylinder.

Kev beat me to it!

So what frequencies do you use? I use the sonic method on my 996 belts, but haven't tried it for the DD because I couldn't find the frequencies to use.

2v (Non DS) 145Hz for the Vertical and 160Hz for the Horizontal

Nice one - thanks!

No problem Simon, figures were sent to me by Gates

Do you check it with a sonic screwdriver :lol:

Well I used a 5 mm on the horizontal and a six on the vertical. Making sure it fits through snugly but a 6 and 7mm doesn't

Of course! Don't you? :D

WHO does use one :p

harry potter and mr zulu use one (on star trek)i tried it but 160 hz is radio 3 i think !.
:lol:

Ahhh. The Pandora's Box that is belt tension. I guess if you're using a Frequency Meter of some sort, then things are pretty definitive, if not just a little bit anal, especially on the 2 valvers. As regards the Allen key method, then I reckon your 5mm is my 3mm or perhaps my 8mm! The point being, the acceptable parameters are quite large. Don't fret (pardon the pun), just don't over tighten it, get out there and thrash it! After all, you're changing 'em every few hundred miles.
:frog:

Ps. My Missus has got a Sonic Screwdriver. I think she keeps it in her bedside drawer?
:roll: