Throttle problem/Surging
- Thread starter HyperPhil
- Start date
This may not be your problem, but, I was noticing some surging / stumbling on my 2015 821. Most noticeable at 80mph or above, it seemed that if I got off the throttle slightly it'd decelerate abruptly and then recover. I also noticed very subtle stumbling under steady throttle. It wasn't consistent for me either. Dealer took a week to go over the bike and found there was a short in the o2 sensor wiring, hidden inside the protective sheath. New o2 sensor and it's a different bike.
-- Nathan
-- Nathan
Joined Oct 2015
545 Posts | 0+
Minnesota
I'm not sure, I'll try to remember to dig up the paperwork tonight when I'm home and post here. They had a hard time finding it as the short was hidden by the sheath, but it sure made a difference!
-- Nathan
if it really is an o2sensor you easy can test by your own.
disconnect both connectors to the o2sensors and drive.
lambda regulation is disabled with this, but bike will run smoother, you will see.
yellow check engine light will burn, but this does not matter for testing. bike completly runs via internal map, also in closed loop, as it always does in open loop. now it does not run with lambda 1 = about AFR 14.7 but richer in closed loop.
if it runs fine without o2regulation, you know that 1 or both o2sensors are faulty.
disconnect both connectors to the o2sensors and drive.
lambda regulation is disabled with this, but bike will run smoother, you will see.
yellow check engine light will burn, but this does not matter for testing. bike completly runs via internal map, also in closed loop, as it always does in open loop. now it does not run with lambda 1 = about AFR 14.7 but richer in closed loop.
if it runs fine without o2regulation, you know that 1 or both o2sensors are faulty.
I think the ideal setup would be to disconnect O2 sensors, and then use a fuel module to create a custom map.
If only there is a way to easily disable the O2 sensor without spending $500 on a Rexxer Evo.
exactly
but for quick testing, just disabling o2sensors by disconnecting the cables to them is an easy way to check if o2sensors are faulty
the advantage for a direct mapping like rexxer is, that it's stored in the bikes ecu directly and nobody sees you have modified anything because you have no additional hardware installed. and they are able to disable o2sensors and exhaust flap.
the advantage of a fuel module is that you can create and test your own mappings until you are completly satisfied. the disadvantage of it is, regardless which brand, that it has a little time delay to adjust fueling. if this matters or not ? i suppose in road use not. and of course the additionl hardware.
so, it's up to personal preferences what to prefer
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Hey guys, does anyone know if removing the battery from the bike affect the rapid bike system?
I have to remove my battery between rides to hook it up to the tender. Do you know if this is gonna be an issue ?
Thanks
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I have to remove my battery between rides to hook it up to the tender. Do you know if this is gonna be an issue ?
Thanks
Sent from my iPad using Tapatalk
Just ordered the rapid bike evo off of eBay for $275. Took me a while to haggle with the seller but finally got it down. I hope it does the trick and makes the bike less jerky.
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Sent from my iPhone using Tapatalk
Joined Oct 2015
545 Posts | 0+
Minnesota
Was that the used one on there? I thought about messaging the seller. Damn good price!
Yeah it was the used one. He wanted $400 but I talked him down to 275.
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