So I got my inlet rubbers from China for 15 quid last week. I'm finally at the point of putting them back together so I made a little album and have some info on them.
In short, I was very happy with them until I was fitting the last one and the post to connect a balancing tool came out.
In long, I started with cylinder 1 on the left of the bike. As per the photos on the eBay ad they do not come with the caps to cover the vacuum gauge connection points, but that's no matter, the ones from my original rubbers are still OK. I did one at a time to try and work out which ones went where. I think there are basically 2 left ones and 2 right ones not necessarily one per each cylinder. They are labelled incorrectly on the rubbers themselves.
I have my carbs off right now so I was able to try them on the carb ends with space to get a good view and they looked pretty decent. I put a bit of engine oil around the engine side, cleaned up the metal of the block with a rag and some solvent and they fitted very well.
Until I got to the last one, for some reason I fitted the vacuum gauge cap and then decided to pull it off again. The whole post came off with it. There is a reasonable chance this will happen with the others as well although I haven't checked them yet. It looks like they are only secured in place with some resin of some sort and this one did not receive a good enough dollop in the right place to hold it in. In comparison to the original Yamaha ones they are also held in with some kind of adhesive resin but it looks much more robust. It's a square evenly placed around the whole post like a machine did it. The Chinese ones just have a dollop like somebody applied it with a syringe.
I cannot try them with the engine running yet as I have just fitted a new cam chain and I'm waiting for a new tensioner gasket.
I'm going to attempt to fix it as I think it might be OK, this is where I ask for some advice, I have to hand fibreglass resin (for boat repairs and whatnot) vulcanizing rubber glue (for bicycle inner tubes) or superglue. What do you guys recommend?