Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Drive belt tension

Hi all--I notice my drive belt is running about 1/8 closer to the near side than the middle of the sprocket. It is fairly easy to get the belt to run true, but I was wondering if any one has heard any thing other than what is mentioned in the handbook (10mm) for belt deflection? I've ordered a belt tension scale from Motion Pro as that is what most of the Harley guys use.

Oh no, not something else to worry about?

In hindsight, mine was way too tight when new, but now it's given up some of its newness (3000 miles) it has what appears to be about 10mm of play in it which feel about right, mechanically. The drive is quieter and more smooth now, albeit still with banshee screaming from the BB of course. Reckon they should not be setup too tight overall.

You should get about 10mm when pressed in the centre of the belt. The belt does give a little after a while. You'll know when it's moved on the pulled to far it gets very noisy.

My dealer told me the belt is too loose if you are able to twist it 90 degrees when it is in place on the car...

Agree that it's hard to judge 10mm of deflection...

i've wondered how to properly measure the 10mm as well as my car's had 7 belt adjustments by the dealer and we both laugh about trying to dial in 10mm. My belt struggled to stay true and alway found it's way flush against the pulley which makes a hell of a lot of noise. i'm on bevel box #3 and 2nd pulley and things seem good so far. fingers crossed.

That's a good way to tell ...

According to the PDI check list point 31 a 1/4 turn is correct.

To measure 10mm I would think it would be possible to use a wooden dowel or thin baton held up to the belt & against some fixed point on the car or ground, mark where the belt sits & a second mark 10mm apart & then check the deflection. I have not tried this

Hello all, my first post.

I've been a gear head all my life and tension on belts and chains have popped from time to time.

I've just become interested in the M3W and thought I'd get the real info from the horse's mouth instead of the other end.

I've been into street rods for many years and have been riding two wheelers for 50 years or so. Right now I have three Harleys and the latest '09 CVO Road Glide has the Gates type Polychain like used on the M3W.

This may sound very basic, but the main thing to remember is that you cannot properly check belt tension when the rear tyre is on the ground. The chance that side of the belt that you're checking tension on is in a bind by vehicle loading one side of the belt making checking that side almost impossible.

Harley belts tend to loosen up as the bike warms up with some mileage, which I'm sure the M3W will do as well.

I'm enjoying reading about the M3W hear.

Thanks from a novist.

Welcome to TM, I am sure the M3W members will respond in more detail.