Ordered and had installed Screaming Eagle Stage IV upgrade for my 2020 Deluxe from my local dealer, 107 to 128. Collected it today and they mistakenly ordered and installed the wrong kit, 114 to 131. They are very apologetic and it will be back in on Monday to install the correct kit, but having driven it home and back there, I am concerned of any damage to anything on the bike from the incorrect kit?!?
They said the only difference between the two are the pistons, and assure me there is no concern. I don’t know enough about the technical side to be confident it will be ok, I trust the dealer, but do you have an opinion?

 

I have a very dumb question - Why not keep it at 131?

 

Is there actually a difference in the kit? I am pretty sure the different stroke from the 114 and 107 are the difference in CI.

The bore is the same, pretty sure the exact same pistons as well, anyway, I can't see why it would be a problem if nothing happened on start up, except it seems the dealer doesn't have a clue.

 

I'm guessing, but base cylinder thickness might be an issue. If it's too thin, I've heard of the flange breaking off. If that hasn't happened, you should be OK.
I would be concerned about how you get that far into an engine without noticing the parts aren't the right ones.

 

Stroke on the 107 is 4.375, the 114 is 4.5. So even though it bolted on the Compression is going to be real Low.

 

Without knowing for sure the difference in the pistons, I'm betting this is the correct answer.

 

Yes they mentioned this would be the result. My question though is if they now change to the correct kit, is there going to be any long term side effects from their mistake, or no issue at all?

 

Deck height is the issue. Piston pin height is 1/2 of the stroke distance delta (1/8") , so pin height for a 107 piston is 1/2 of 1/8", or 1/16" (.0625"). This drops the compression from 11:1 to 9.75:1.
Let them fix it.

 

if you don't mind an opinion, you have two issues

one....your bike has incompatible parts, the likely outcome is no big deal, get the correction made and you'll probably be fine

second issue....you have a partner who sounds less like a mechanic, and more of what mechanics lovingly refer to as 'parts changers'

it sounds you like you have two changes to make now

 

Comforting to hear once it’s corrected there should be no long term issues.
And you are right about the ‘mechanic’. Pity when you want to support your local dealer.