Lean vs Rich, Exhausts and the lust for more performance. Honest Question.

Hatata

.060 Over
Joined
May 12, 2020
Messages
103
Location
Calgary, AB
Ride
Triumph RocketR
Hello everyone.. I have seen quite an influx of exhaust posts recently and lots of folks lusting over squeezing every inch of performance from the 2020 Rocket. Nothing new really almost every bike with a forum has people agonizing over fuel maps and getting their engine to perform above factory. I am not a mechanically inclined person but wanted to share my mindset and tell me if I am right or wrong in my fears to mod any engine components above stock. So.. yes I would love to have my 2020 R sound a little more aggressive... I see a lot of people commenting on how lean the bike is running to meet emissions standards ..etc. Everyone wants a new tune to get around this obviously. My question is... if Triumph engineered the bike to have a certain type of fueling wouldn't the entire engine's longevity and performance be built with that in mind? Meaning if I re-tune my bike there are no guarantees that internal components or oil change intervals are now accurate or have been tested by Triumph to be parameters the engine can sustain for its life time? That is what always worries me when I am like every one here wanting to hot rod the bike further. Not to mention give Triumph an excuse to duck out of any warranty claim related to the engine or power train.

My point is in my mind Manufacturers likely design the entire bike around the engine. The transmission has to be able to accept a certain amount of power without over stressing. So I am always worried that mod'ing an engine is just a pathway to less reliability and especially with a new platform like this not enough mileage on the engine to understand how components will fail, and not enough third party manufacturers selling strengthened components.

Am i totally off base to feel this way? is it a risk vs reward at the end of the day? Or are Engines not as sensitive as I think?

Looking forward to your thoughts and discussion. I do not claim to be an expert on any of this.
 
@Hatata you pose and excellent question about longevity. With some engines, that may be a great concern. However, with the 2.3L or 2.5L engines, i do not think they can be really stressed enough with regular riding to be a concern. Now for those who race more than the just ride, there could be. But those engines usually get more care due to oil change intervals being closer than OEM.
With running lean, that all by itself can cause any engine to fatigue early and of course most of the exhaust you ahve been reading about will cause a leaner situation. Without having scientific data to abck it up, I think one should absolutely change the fueling to me less lean.
 
Fueling is important. It must be balanced between the intake and exhaust for most efficient burn. As the bikes come lean from Triumph, adding a little fuel to correct the AFR will only naturally ad power and improve efficiency. I would not fear an AFR modifier when they become available.

You are correct the 2.5L engine has been made a little less stout than the 2.3 L engine. Several components have been lightened as they were way overbuilt in the 2.3 L engine. However both of these engines are robust enough to make up to double the output Triumph has set for the OEM numbers. Most engineered things made for the general public to use are rated at 50% to 70% of actual stress tolerances. (Except for something that is used for a special purpose and weight is a factor. (Like a spacecraft or beer can one time use.)
 
I work for Harley as a dyno tech in research and engineering. It’s an amazingly complex task to design a compliant vehicle that works. Beyond making a fun, safe, reliable vehicle, it must also meet regulatory laws for a variety of things like noise, emissions, lighting, electrical interference, in some countries max power, fuel economy......and on and on!

The end product is a compromise. Changing things doesn’t necessarily make anything bad, unless poorly executed. It might not be legal, adding fueling and a better flowing exhaust makes motors happy. It also increases tailpipe emissions! Can’t have it all!
 
Hello everyone.. I have seen quite an influx of exhaust posts recently and lots of folks lusting over squeezing every inch of performance from the 2020 Rocket. Nothing new really almost every bike with a forum has people agonizing over fuel maps and getting their engine to perform above factory. I am not a mechanically inclined person but wanted to share my mindset and tell me if I am right or wrong in my fears to mod any engine components above stock. So.. yes I would love to have my 2020 R sound a little more aggressive... I see a lot of people commenting on how lean the bike is running to meet emissions standards ..etc. Everyone wants a new tune to get around this obviously. My question is... if Triumph engineered the bike to have a certain type of fueling wouldn't the entire engine's longevity and performance be built with that in mind? Meaning if I re-tune my bike there are no guarantees that internal components or oil change intervals are now accurate or have been tested by Triumph to be parameters the engine can sustain for its life time? That is what always worries me when I am like every one here wanting to hot rod the bike further. Not to mention give Triumph an excuse to duck out of any warranty claim related to the engine or power train.

My point is in my mind Manufacturers likely design the entire bike around the engine. The transmission has to be able to accept a certain amount of power without over stressing. So I am always worried that mod'ing an engine is just a pathway to less reliability and especially with a new platform like this not enough mileage on the engine to understand how components will fail, and not enough third party manufacturers selling strengthened components.

Am i totally off base to feel this way? is it a risk vs reward at the end of the day? Or are Engines not as sensitive as I think?

Looking forward to your thoughts and discussion. I do not claim to be an expert on any of this.
Really liked this post.
 
so.....if we change the exhaust from the headers back...get rid of the cat box and make a nicer flowing set of pipes, im guessing the bike will run leaner right?...Has anyone checked how lean the bike is at stock on a dyno???..not sure...If you piggyback a PCV and use it as a fuel injector would this help?
Also...once the exhaust has been altered....leave the nb02 sensor in place and do the 12 min tune b4 twisting the throttle. I understand the o2 sensor only trims at idle right?...so would the ecu adjust as the 02 sensor is telling it to do cos now things are a bit leaner..
Would a WB02 sensor tell more information to the ecu...which also could be too much info i guess highlighting other fuelling problems.
So much to learn...
 
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