Reducing Decel Popping?

[kaivalagi]

Hi all,

I have a stock roadster with standard air in and header but with straight through 3 into 1 link pipe / end can that frees things up a little

I've loaded the tors map (20776) onto the bike but with only a short length of link pipe and outlaw style can there isn't as much restriction...so I have decel popping.

I understand from some posts that adding some fuel percentage to the map will help reduce this (not being too lean) but I'd like some advice on the edits needed.

Am I right in thinking that upping say 5% on the 20776 F1, F2 and F3 tables is what's been done successfully in the past? Would I need to consider the L and I tables for any reason? Maybe up the idles by 5% too?

I've pinged Hans0 about my bike but haven't managed to get a sensible map through yet so an trying to get to grips with it myself...

If any one has a similar setup and a related map that would help me please let me know...but I really want to understand the basics of adding fuel to maps to reduce decel popping etc when running too lean...

Cheers
Mark

 

[kaivalagi]

Just done comparisons on map files and it does seem that adding 5% on the full range of F1, F2 and F3 numbers found in the 20776 map is what's been done (+8% with ramair), as well as upping the rev limit to 7K, lowering the trigger temp for cooling to 96C and upping the speed limit to 299....

Anything I've missed? If I take the 20776 map and add 5% for all three F tables it should help with the decel popping right?

 

[joesoap]

get it while you can...another 5 years and there will be posts like "how can i get my electric motor to sound like it pops on decel"

 

[Jvheli]

Hi all,

I have a stock roadster with standard air in and header but with straight through 3 into 1 link pipe / end can that frees things up a little

I've loaded the tors map (20776) onto the bike but with only a short length of link pipe and outlaw style can there isn't as much restriction...so I have decel popping.

I understand from some posts that adding some fuel percentage to the map will help reduce this (not being too lean) but I'd like some advice on the edits needed.

Am I right in thinking that upping say 5% on the 20776 F1, F2 and F3 tables is what's been done successfully in the past? Would I need to consider the L and I tables for any reason? Maybe up the idles by 5% too?

I've pinged Hans0 about my bike but haven't managed to get a sensible map through yet so an trying to get to grips with it myself...

If any one has a similar setup and a related map that would help me please let me know...but I really want to understand the basics of adding fuel to maps to reduce decel popping etc when running too lean...

Cheers
Mark

If your only trying to fix decel popping it isn't necessary to add fuel to the entire table, just the area where the popping takes place.

 

[Jvheli]

Hi all,

I have a stock roadster with standard air in and header but with straight through 3 into 1 link pipe / end can that frees things up a little

I've loaded the tors map (20776) onto the bike but with only a short length of link pipe and outlaw style can there isn't as much restriction...so I have decel popping.

I understand from some posts that adding some fuel percentage to the map will help reduce this (not being too lean) but I'd like some advice on the edits needed.

Am I right in thinking that upping say 5% on the 20776 F1, F2 and F3 tables is what's been done successfully in the past? Would I need to consider the L and I tables for any reason? Maybe up the idles by 5% too?

I've pinged Hans0 about my bike but haven't managed to get a sensible map through yet so an trying to get to grips with it myself...

If any one has a similar setup and a related map that would help me please let me know...but I really want to understand the basics of adding fuel to maps to reduce decel popping etc when running too lean...

Cheers
Mark

Also, there are new tools available on the task bar area...labeled resourses. If you are using a smart phone, hold sideways to view. Check there to see if a tune suits your set up. Hanso has asked that we share tunes.

 

[barbagris]

When you say decel popping - what rpms?, what TPS%?

 

[kaivalagi]

So is it bad practice to just apply a small percentage hike on all cells in the F1 to F3 tables? That's what I've seen in some of the modded maps I've gotten a hold of...and to confirm is it just edits to the F tables, whether it be all cells or specific ones for specific rpm/tps? No other tables right?

I'm not sure what RPM exactly my popping was occurring, I need to take the bike out again and see and take note properly...it was low to mid rev range from memory (about 3000 to 5000rpm I'd say), and for TPS% I'm not sure the decel happened in different rev ranges for different gears...might it be best applying the increase for all tps in the rev ranges affected?...if I'm getting TPS and RPM specific (i.e. cell by cell) then it feels like I should just go to a dyno for it.....

For the small mod I have made is it standard practise to just add a few % on all cells in the f1,f2 and f3 tables and test ride?

Here's the bike mod, just from OEM headers to small can. nothing major, just a link pipe from headers to a can:

I think I am getting the gist of it thanks to the little snippets of info but if you guys could give me some reassurance I'd appreciate it....I will dyno later once I've made more changes to the bike but I'd sooner not yet given how little I've changed...

 

[Claviger]

It should pop.

It pops stock, but you can't hear it because of the maze in the mufflers.

It pops because the stock tune is trash.

 

[kaivalagi]

So Dyno on PCV is the only real answer, even near stock? I'll look into that once I've spent more on upgrades for air in and headers...

I think based on all this I'll try and do a rev range increase of f tables bit by bit until the popping is reduced...if that proves too hit hit miss I'll fall back to raising the whole range of numbers equally.

 

[John Miller]

If its decel popping wouldn't it be at 0% TP. I had similar issues with a number of tunes I tried - I had to tweak my own tune no popping now and running sweet as. Turn off your O2 sensor and try it.