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Help Please...Learning Shim Tuning

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Hi guys how are you all..?

Im looking for help,im no newbie with suspension but shim stack tuning is something i have basically nil experience off other than swapping stacks from pre determined libraries when doing service work for a large brand...

I work predominantly with sports-bikes so from what I've seen most stacks are single stage pyramid stacks in shocks.

Ive studied fluid mechanics years ago at uni (bernoulies etc) also cfd and cad work.

I do not have a dyno and I'm not looking at designing new pistons, so doubt ill be putting my cad/cfd skills to use.

I am about to invest in shim restackor and you guys rave about it, not so much so on the independent suspension forum and that forum is quite taxing im finding. Im not after an answer on a plate but i want to learn and im prepared to put the time in to do so.

I currently have a showa shock with a 40mm hmas piston, its ports look ultra restrictive and it appears to have two stage stacks (is that correct..?) and id like to improve it generally, im told the shock has no general performance issues by my friend but its oem so I'm sure can be improved, its also a bladder shock and not floating piston.

I can write up the stacks and piston data if people like.

My plan was to port the piston or chamfer the ports and to face the pistons with 1200grit wet n dry.

I was led to believe this will improve sealing and i remember fluid flow does not like sharp angles!

I know a stack can take a few goes or more to get spot on, but in general i think sportsbikes would be simpler due to the topography we encounter compared to you mx guys...

Ive read many of the threads here but some of it is over my head as ive jumped in at a level too deep.

Thanks in advance

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