The CB1100 Community Forum

Pity it doesn't fire 4,3,2,1. God knows what would happen next!

NHCB, one thing that REALLY smooths out the throttle at low openings is controversial: pull your right-hand side cover, disconnect the O2 sensor cable, and plug in a $20 resistor like you can find in a eBay search for "CB1100 O2 eliminator." I say "controversial" because many people think O2 sensors are about power. They're not -- they're about emissions. They only affect the bike at low RPM and small throttle openings, exactly where you're describing the problem. They're designed to keep the bike very lean at those openings for emissions purposes. They're not atmospheric pressure sensors or ambient temperature sensors -- most modern bikes have those, and they've nothing to do with the O2 exhaust sensor. I'm just saying, for the level of frustration you're describing, this is a relatively cheap and easy possible fix. Just unplug (under the side cover -- there's no need to physically remove the sensor from the exhaust, which would be a PITA), plug in the resistor, put the side plate back on, and see if it works. If not, no big whoop, just plug the sensor back in. It's worked for me on snatchy fuel injected bikes.

I tried adjusting the screws on the 1 and 2 throttle bodies.... And as I expected, no better. Siggy, I will try your suggestion. THe bike does run ok on when it is warming up, for the first 5-10 minutes. From what I read online the 02 eliminator basically keeps it in that mode. Only potential down fall is a little bit of fuel milage, which I dont mind that if it solves the problem. I didnt buy this bike for mileage or commuting, I bought it for enjoyment. So we'll see how it goes.

Worked for my brother on his 07 Multistrada 1100 which had run horribly at low rpms. Minus the O2 sensor, it cleared right up. Let's face it, they do choke these engines. opening them up does wonders.

(04-28-2015, 01:21 AM)NHCB_imp Wrote: [ -> ]I tried adjusting the screws on the 1 and 2 throttle bodies.... And as I expected, no better. Siggy, I will try your suggestion. THe bike does run ok on when it is warming up, for the first 5-10 minutes. From what I read online the 02 eliminator basically keeps it in that mode. Only potential down fall is a little bit of fuel milage, which I dont mind that if it solves the problem. I didnt buy this bike for mileage or commuting, I bought it for enjoyment. So we'll see how it goes.

For what it's worth, my fuel mileage got substantially better after the O2 eliminator, in addition to smoothing throttle response. Don't ask me why! Maybe the herky-jerky over-lean stock fueling ends up with more fuel being shoved in there by ham-fisted me. But regardless of the cause: better fuel mileage for me.

Siggy, have you made any other mods such as a re-flash or different exhaust can?

NHCB , have you had a chance to ask a different mechanic for a second opinion?

Many thanks!

(04-28-2015, 12:14 PM)lemontree_imp Wrote: [ -> ]NHCB , have you had a chance to ask a different mechanic for a second opinion?

Many thanks!

I have talked to a few different people, one guy I know at the dealer, a friend that owns a small shop, and just a few days ago found out there is a local guy with a dyno. We've talked about different things but all seem to think its lean fueling. So why did I send the ecu to Guhl twice????? And have it richened twice???? I wish I didn't send it. That's a lot of money that could have been spent elsewhere. I'm going to bring it and have the guy put it on his dyno to see what's going on. He's just waiting for a new part because lightning did some damage to his machine.

I just looked into the O2 eliminator. One being offered came with a threaded plug and copper washer. Are those for the exhaust sensor ?

Yeah the plug and washer are so you can remove the o2 sensor and plug the hole. But you need to drop the headers to get the sensor out so its a little extra work.