I have a rattle behind the starter clutch on a gs850 Suzuki. What could it be? Bearings?

I would normally it is probably stuck, but the starter motor doesn't have the normal bendix on a spiral grooved shaft. It looks like it is permanently connected. I tried to see if there was some type of starter clutch behind it, and there is. It should release when the starter stops spinning.

Suzuki Gsxr600 Srad Gsxr750 Oem Gsx1300R Starter ...

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SUZUKI GSXR600 SRAD Gsxr750 Oem Gsx1300R Starter Clutch - $99.99. FOR SALE! 1999 Hayabusa (GSX1300R) - STARTER CLUTCH (MODEL K3).

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Starter clutch

https://www.google.com/search?q=1999+Suzuki+GSX-R+750+starter+clutch

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It is on the outside of the engine and just unbolts.

the cable or the ratio

Duplicate question. Keep in mind unless kept on a battery tender these batteries are good for one or two years max, no matter the brand.

Check the compression on each cylinder. Chances are good the bike needs a valve job.

Sounds like the starter clutch is worn out its a one way clutch and when it will slip and catch making noise.

Obviously the CDI is picking up power from the starter button. Check the ignition key switch for proper operation. Chances are that whatever fried the loom also fried part of the switch. Alternate to that, trace the wire powering the CDI system, disconnect it at the source (starter button connection), then find a power source that is live only when the key is turned on and then hook the CDI wire up there.

an I get a “very helpful” rating on this answer?

It is not a big job if you know what to do and you have a rotor puller. But you may likely cause big $ damage if you don't.
The "starter clutch" is on the end of the starter motor and when activated turns an idler cog, which then turns the clutch starter set. This clutch starter set is behind the magneto rotor (flywheel) and should not be the problem. To remove the rotor you will require an appropriate size rotor puller available from most larger bike accessories stores for under $20, or the Suzuki Special Tool for 10x the price!
Your problem most likely lies with the starter clutch pack itself and is a parts replacement item.
The link below will provide by exploded view, diagrams of the parts you need to check, at least you can have an idea when you talk to your parts dealer. Cheers.
http://www.cmsnl.com/suzuki-dr650-se-usa_model15962/partslist/