Hi,
I have a 2018 Street Bob (work in progress) and a S&S teardrop air cleaner that I really would like to install (I prefer how it looks compared to the stock one).
I would like to do it now and do the tuning later (I also have a Two Brothers Racing exhaust installed).
I read all the discussions on the need to tune/re map... and I could theoretically wait.
But it seems the bike is already running pretty lean, so more airflow will increase the engine heat... and I really don't need that since I live in Thailand and the weather is super hot.
The S&S teardrop increases the airflow by about 38% compared to stock.
So I am thinking that if I block approx. 38% of the air intake (with tape or something), I can keep the air/fuel ratio as is and take the time to properly think the tuning through (possibly buy a tuner if I decide to do it myself etc...).

Has anyone some experience with this, or another solution?

thanks

 

You dont need a retune on an M8 to run an aircleaner and pipes.
DKCustoms tested this extensively.
A tune will get you more power, but no re-tune will still be good.

 

I still haven't tuned my FXLR and it is running just fine.

 

Thanks guys!
These videos from DK custom are really interesting.
Their point is clear. The M8 engine does't run too lean if one adds a high flow air cleaner or/and a performance exhaust.
A pity though, they don't show the air/fuel ratio chart with both a high flow air cleaner and a performance exhaust.
They only prove their point showing an air/fuel ratio chart with high flow air cleaner.

Am I missing something?

 

They've done more videos than this about it, along with dyno runs. I just didn't link all of them. They have a lot of videos.

 

Cheers mate! You are absolutely right. I am watching them 😉

 

Put away the duct tape and listen to these guys.
Besides, your mathematical assumption is incorrect. And, S&S's claim may be suspect.

 

True!... the maths calculation is wrong.
Thanks for correcting me ;-)
DK Custom and Doc Harley are both confirming that no tuner is required.

 

If the stock air cleaner flowed enough for the engines requirement, then the new air cleaner won't magically push more air in. They can state 38% more flow, but unless you increase your engines requirement with a cam or headwork or displacement I wouldn't worry too much.

 

Thanks Tozco.
I initially thought the combinaison performance exhaust and high flow air filter was enough to get more air flowing and change the air/fuel ratio to a point where a tuner was required.
But it seems not, which is good because at this stage I only do it for aesthetic reasons and I am happy to save some cash.