Moulded bead seat (Hans) - review

[erictharg]

Thought I'd let y'all know how my first go at a moulded bead seat went. You may have seen them in the race catalogues - Real and Hans are two of the brands. Imagine a bean bag using a big stretchy plastic bag, with a valve in the top to adjust how much vacuum you can apply and you'll be close. the idea is you trial the bag to get the right position and amount of beads, then chuck in a load of epoxy resin, mix it to cover all the beads and re-fit the seat. When it's where you want apply vacuum to hold it in place. Next day once it's set you have a perfectly shaped rigid seat.
But at c.£200 for the size you need for an Eleven it is expensive. But I couldn't see anything else out there that would fit the bill apart from the smallest Tillet seat. And by the time you'r added the base mount and covering that was £250 plus.
I tried the dry fit process 4 or 5 time and had it pretty much perfect. Then mixed and added the resin. Seems at first as if you'll never get all the beads covered but after 5 mins of kneading it gets there. But the way the bag behaves once all the beads are covered in resin is very different...
You have up to an hour before it starts to set. I got to to where I thought was right and applied the vacuum. Then got out my portable floodlight to keep it warm overnight and ensure it set. Less than 20 degC and it will take forever. And it was cold last weekend.
Next morning it was all set. That's positive. However it was not where I wanted it to be in terms of position. Not good. I think in the self imposed rush to fit it once mixed with resin I'd not checked all the parameters so it was placing me too far forward. Maybe 90mm from the bulkhead instead of the 40 or so I needed. After trimming off the excess bits I took a hand saw to it and cut off a slice about a 50mm slice from the back. Crude, but worked OK - fortunately. Covered it all in duct tape and it's pretty good now. Not pretty looking mind, but feels so different to the factory seat that had me holding onto the wheel and bracing myself aginst the tunnel with my legs in corners.
Would I use one again? I don't think so. I reckon I could get the same result by firstly cutting some polystyrene blocks to go under the driver's bum and behind the back to place you in the right position, then conventional two pack foam to fill the gaps. For about 1/4 of the cost.
Anyway, I now have a good seat and one less excuse for crap lap times! And a car that's moving further and further from a road car.

[adamwilkinson]

You'll be surprised how much confidence you get from being comfortable in the car feeling how the car reacts through your backside - much more natural and your times will tumble.