See also
IK&P Glues and Repairs

They don’t make the Solar 300 anymore – it’s been superseded by the lighter Twists, although the similar full-coat, white-water Safari is still made All these Gumboats and a few others may benefit from the footrest mod as described below, as might bigger Gumboats which both use a similarly mushy footrest pillow.
Our Solar dated from 2006 and although (or because) it doesn’t get used much it still looks like new. And it’s lost no air to speak of lying in the garden for over a month (can’t say the same for my Incept K40).

But the seat/footrest arrangement is poor, like all Gumos from that era. The seat pivots at the right angle base as you lean on it, because the top edge is attached to the bottom edge instead of the actual boat, like any sensible IK. You lean back, it lifts up – no good. I messed around a lot with my old Sunny before I got smart and simply glued some D-rings onto the top of the hull sides, which Gumo started doing soon after. This way when you lean back or brace against the footrest, you’re locked to the boat and so get more drive.

The pillow thwart footrest is OK, but I ditched that at the same time on my Sunny to use a small Otter box. For the Solar, the g-friend is short and can’t reach the footrest pillow even set right back.

I glued on a pair of big D-rings with Aquaseal, bonding much cheaper PVC D-rings to the Nitrilon hull sides to provide a fixed point to tension the seat back. I did this because the price of RIB hypalon D-rings is crazy: from £20 to £40 for one patch!
I Iused single-part Aquasure urethane sealant/adhesive (‘Aquaseal‘ in North America). Allow Aquasure or similar to half-cure in air for 30 minutes, then stick together and let it ‘seal’ to itself is a way of bonding anything – even non-compatible rubber-based Nitrilon to PVC. SeamGrip is a runnier version of Aquasure to get into cracks and seams and though I’ve not tried it yet, British-made Stormsure is the same thing.
That was years ago. Maybe it worked fine but these days, I’d sooner MYO D-rings from hypalon off-cuts and use 2-part glue.

Then on the Solar I removed the footrest pillow and replaced it with a bit of sawn-off four-inch drain pipe, taping the pipe ends to limit any rubbing against the hull. The seat straps were sewn into a loop and clipped to the D-rings.

This mod will improve bracing in the Solar: the bane of all IKs (and SoTs for that matter) which without bracing are like paddling a log. The footrest (the tape goes through a slot under the pipe) can easily be moved, even when inflated and will transform the Solar which is a nippy IK. The next step would be to fit thigh straps as found on the current Safari – then you can do cool stuff like this – but for the use our Solar gets, the current improvements will do.

Recently I also glued on the later style skeg patch to take the plastic fin. No more faffing about with butterfly nuts and bolts and bits of bent alloy. The patch costs £12 and so does the skeg, which I also fitted to my Grabner Amigo.