Rings gave up on my 954 at 23k, trying to only have it apart one time, getting the cylinders re nikasiled and running 1000rr 13.5:1 pistons, is it worth boring to a 980? I was told to run an 06-07 cbr1000 intake cam on the exhaust side and a custom grind intake, anyone know where I could send the 1000 cam to get the cam position sensor welded on and balanced? Will dual valve springs on intake and exhaust side be stiff enough? Open to suggestions and opinions just trying to learn as much as I can about these engines. Just joined too so here’s a few pictures of my baby, thanks in advance!



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Sounds like a cool project. If you haven't already, make sure to check the 929/954 section for other owners that may have done similar mods

As far as the bore goes, it's going to be a tradeoff between power and reliability. The risk of overboring is increased chance of warpage and heat deformation which is fine for a race bike, but may be undesireable for a daily. If I'm not mistaken, the 954 is just a bored out 929, so she might already be a bit thin. That said, if your rings let go, you might be looking at cylinder wall damage anyway, so you might already need a bore. I'd reserve judgement until it comes apart. Once you've got the jugs off, you can walk em down to a machine shop and get their opinion. Those guys will know a hell of a lot more than us common plebs. They'll also be able to handle the camshaft modification. If not, they'll know who will

As far as the valvetrain, you've got a couple of risks that you need to weigh out. High compression + increased lift + high heat & rpms can equal trouble if things aren't spec'd out right. The last thing you want is for the pistons to crash into your valves. Make sure to leave room for timing advance (if any) along with heat expansion. As always with engine modification, the biggest gains come with the biggest risks, but if you're diligent or follow a known working formula, you can get some great results

The spring specs will be available in the FSM for the respective models, but it's probably good practice to have them measured. You may also need to look at the head gasket and other potential 'weak links.' If it's your first rebuild, I'd really recommend getting a professional opinion before proceeding with valvetrain modifications. I'd start at a machine shop or qualified rebuilder. Just remember that they're a business not a charity, so do your homework and try not to waste their time

If you want to learn about the engine, you're on the right path. May as well start ripping it apart and checking for damage. Make sure to clean out any of the oil passages where bits of ring may be lodged or else you'll get a drastically shortened service interval

Good luck and keep us posted on your progress