[AFP]

I was looking around for engine mods for more speed and came across this:

DHM High Compression Stock Bore Piston for 2022+ Honda Grom/ Monkey

Big Time Small Bore

mnnthbx.com

Has anyone done it? Is it easy? Will I need to get my ECU reflashed again? I have the CJR ECU flash but with just aftermarket intake so far.

Anything else to consider with this upgrade?

 

[Johnnie5]

Check the fb groups and youll see plenty of those pistons have failed supposedly due to low quality gas

imho if you are going to go to the effort then put the full bigbore kit which has more meat on the piston

 

[AFP]

Check the fb groups and youll see plenty of those pistons have failed supposedly due to low quality gas

imho if you are going to go to the effort then put the full bigbore kit which has more meat on the piston

Do you mean from running less than 91 octane? I could definitely see detonation breaking a piston due to higher compression ratios and low octane fuel. I already run 91 octane with my ECU tune.

I haven't really considered doing the big bore kit. Is it a ton of work? Are they reliable? How much additional power can you pick up from it?

 

[Johnnie5]

Do you mean from running less than 91 octane? I could definitely see detonation breaking a piston due to higher compression ratios and low octane fuel. I already run 91 octane with my ECU tune.

I haven't really considered doing the big bore kit. Is it a ton of work? Are they reliable? How much additional power can you pick up from it?

well theres various opinions about why they went pop, they all crack the same way

have a look at the fb groups and theres plenty as well as reviews on those that have done the bbk as well as rhe graphs etc , in particular the 2022+grom group

bbk is exactly the same amount of work as doing a piston change

no brainer imho if you are considering doing the piston anyway just go bbk otherwise just stay stock

and while you are at if do the cam for the full experience