Twinning Bands - How tight?

[davemanroe]

Hi,
Just a quick question. When assembling twinning bands, how tight do you do them up to hold the cylinders in place? I thought I'd best check if there was any standard 'good practice' out there. I'm assuming it is fairly tight, but not enough to strip the threads!

Cheers

DR

[peteroadie]

If you tighten them up enough to strip the threads you either have substandard bolts or Arnie's arms.

Any movement of the bands should be avoided and you have to factor in the different expansion / contraction rates of the metals involved. Best to do it with empty cylinders and when it's cold.

Take it you are just moving them up / down to adjust your trim ;)

[Howard Payne]

Tight

It's more about the quality of the bands in the first place though TBH

Decent quality, thick beand remove a lot of the stress from the manifold itself, so in some ways - they're the most important bit.

It's well worth paying a bit more for some decent quality bands IMO

[Craig]

Just two clicks of the elbow should do it...

As everyone has said you need to tighten them until there's no discernable movement.

[davemanroe]

Thanks for the answers. I'm using Agir Brockk bands and manifold (came with the twins); it's just I had to adjust the bolts (too short) to incorporate my wing and plate. So it's as I thought, tight enough to stop movement, and no need to break out the old torque wrench.

Cheers

Dave.

[BigBlueTech]

I agree with the tight idea. In addition you should also measure the distance of the gap at the top and bottom of the twin set to make sure it's the same. If not you either have to move the manifold in or out. Also you might want to think about using innertube rubbed between the bands and the tanks to prevent rubbing and pitting your cylinders.