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Too rich - washing cylinder walls?


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I see a lot of talk on how too rich will wash cyl walls and cause glazing/damage. Currently I run 10 afr on boost, 10.5 - 12.8 off boost. My pilots are too big, 47.5. The reason for that was a mysterious hanging idle, which now I'm certain was because it was too rich, not lean, as the idle dips when pulling the clutch in. I'll fix that eventually.

My mains are stage 5 from Eblag, (forgot the exact #) as I was hitting 14 afr on boost. 3 needle shims. Overall it runs pretty great, if I go WOT before boost at low rpms it bogs a bit, but if I roll on and go into boost it feels amazing. Should I be concerned about cylinder damage at these AFRs? gas is very iffy here (bumfuck America) and other tuners don't trust the 91/93 at all. For this reason I'd much rather keep it rich, but I don't want it to be too rich. Thanks.

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Personally I'd try to not go richer than about 11:1 and with decent EFI control maybe 12:1, but with carbs AFR is a crap shoot! IMO as long as everything else is ok ie. Ignition retard on boost, boost control, cooling a 14:1 AFR on boost isn't bad just not optimal but if one of those things gets out of whack then that's why richer mixtures are recommended but tooo far is also not good - excess fuel through the turbine can burn up blades!

Eblag jetting - stage 5 means nothing! Garage and seat of the pants tuning can only take you so far - put the bike on a dyno and get it set right without guesswork!

Edited by Gixer1460
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Posted (edited)
5 hours ago, Gixer1460 said:

Personally I'd try to not go richer than about 11:1 and with decent EFI control maybe 12:1, but with carbs AFR is a crap shoot! IMO as long as everything else is ok ie. Ignition retard on boost, boost control, cooling a 14:1 AFR on boost isn't bad just not optimal but if one of those things gets out of whack then that's why richer mixtures are recommended but tooo far is also not good - excess fuel through the turbine can burn up blades!

Eblag jetting - stage 5 means nothing! Garage and seat of the pants tuning can only take you so far - put the bike on a dyno and get it set right without guesswork!

I want to dyno it, I'm just worried it'll get too hot being ran up so hard without good airflow. 

 

To lean it out, would adjust base pressure on the fpr help at all? or will that not really affect mixture 

Edited by rerb
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10 minutes ago, rerb said:

I want to dyno it, I'm just worried it'll get too hot being ran up so hard without good airflow. 

If a dyno doesn't have decent cooling fans - i'd find a better dyno! Insufficient cooling is never good whether its NA or turbo !

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16 hours ago, Reinhoud said:

Is it blowing black smoke?

Not that I can tell. Again, if it wasnt for people telling me that I could be washing my cylinder walls I'd be happy to run it the way it is. 

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On 8/5/2021 at 11:36 AM, rerb said:

Not that I can tell. Again, if it wasnt for people telling me that I could be washing my cylinder walls I'd be happy to run it the way it is. 

I don't think it will wash the cylinders..

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