Starting problems

[Everpix]

With all the knowledge on this site I hope someone knows a solution.
When I try to start, many times there is a lot of rattling sound without rotating of the engine.
As if the starter sprocket doesn't get into the right position.
I already bought a better better starter motor and new battery.
The former owner explained that during a large maintenance job he replaced the starter sprocket in the engine by a better one with rollers, specially made by Six Center in the Netherlands.
But that was some years ago.
What may be the cause of the rattling problem?

[aahrens1]

This is caused by wear of the surface where the rollers are in contact with. I had the same problem, diameter was at service limit.
I bought this :
https://remotion.jp/archives/8232
They also offer new primary chain guides and tensioners.
https://store.remotion.jp/products/detail/208

[Jeff Bennetts]

Do you know if synthetic oil has been used in the motor lately, this has been known to cause the starter gear not to engage. Regardless a quick way to clean the rollers of the gear is to remove your sump pan, remove your starter and spray carb cleaner into the case onto the starter gear, hopefully cleaning any varnish, or left over residue.

[Dynamohum]

My 82 did that using Amsoil but only if I hadn’t started it in a week or so. On tour starting daily even on cold mornings it always started. This only began after reaching 100,000 miles though.

[Everpix]

Thank you all for the tips, when it gets worse I will figure out what the next step will be.