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I doubt you will hurt the engine in anyway and it may or may not effect performance. My concern would be the pipes. I have had a lean tune turn a major brand name muffler blue and we all know factory tunes are very lean.
With closed loop ESPFI and riding around mostly within a quarter throttle condition with NB O2, it won’t hurt anything at all. I tested this with my own bike (‘19 EGS) and the performance difference without retuning was substantial. Looking at the AFR and other charts, there’s plenty of range within the factory tune to accommodate uncorking the intake and exhaust.
I didn’t retune until I changed the factory headpipes but I’m still running the factory NB O2. I was thinking I’d re-cam but I have gobs of low end torque the way I’m set up now, but I will be going WB O2 with the Auto Tuner pretty soon because I’ll be 10,000 feet higher in the Summer.
I'm no expert but everything I've read says you'll be way too lean. They're arguably too lean right from the factory, so a pipe will only make it worse. I personally wouldn't run it without a tune, but that's just me. Enter at your own risk.
I'm no expert but everything I've read says you'll be way too lean. They're arguably too lean right from the factory, so a pipe will only make it worse. I personally wouldn't run it without a tune, but that's just me. Enter at your own risk.
Actually, comparing the Air/Fuel Ratio (AFR) charts for the actual tunes, they’re not “too lean” from the factory. There are times the ECM will command a lean or rich condition, but it’s based on numerous variables but never during a cruise condition. And again, I’ve tested this myself and compared the numbers. Additionally, without changing the air cleaner, you’re not allowing any more air into the engine than what was allowed prior to changing the exhaust, so the tune doesn’t need to change.
MB
Last edited by RAVAGE88; Feb 21, 2020 at 12:38 PM.
Actually, comparing the Air/Fuel Ratio (AFR) charts for the actual tunes, theyre not too lean from the factory. There are times the ECM will command a lean or rich condition, but its based on numerous variables but never during a cruise condition. And again, Ive tested this myself and compared the numbers. Additionally, without changing the air cleaner, youre not allowing any more air into the engine than what was allowed prior to changing the exhaust, so the tune doesnt need to change.
MB
I also was seeing reports tgat the m8 is not lean from the factory.
Hm, interesting. I dont know enough to argue lol, but some really reputable tuners on the M8 facebook group have said they've dyno'd them and theyre very lean from the factory. I would tend to believe that considering all the EPA emissions stuff.
My stock bike/pipe gets hot as hell which also tells me its lean, but I've also never had a bike with a cat before.
I am personally waiting to do tune, AC, and pipe all at once, but maybe I'm just paranoid.
If not lean, I would think it'd run poorly? My 08 did just from switching to duals to 2-1 without a tune.
If you do go forward, come back with your results, now I'm curious!
Hm, interesting. I dont know enough to argue lol, but some really reputable tuners on the M8 facebook group have said they've dyno'd them and theyre very lean from the factory. I would tend to believe that considering all the EPA emissions stuff.
My stock bike/pipe gets hot as hell which also tells me its lean, but I've also never had a bike with a cat before.
I am personally waiting to do tune, AC, and pipe all at once, but maybe I'm just paranoid.
If not lean, I would think it'd run poorly? My 08 did just from switching to duals to 2-1 without a tune.
If you do go forward, come back with your results, now I'm curious!
Gotcha, haven't seen any of that but will take a look to see if I can draw a reference. Basing my comments on the many bikes I've built along with the tuning and testing I've done on the TC and M8.
Even though the 5 year old in me wants to bolt up the pipe and run it..... i should get an intake and tune. Prob will just do tune and then once i sell myself on the corner pick up an intake.
Lol.
Thanks for the info guys. Appreciate the responces
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