Surging?

[blowndodge]

The last 2 rides I've been on I've noticed that my Nomad seems to have a slight "surging" to it.

I don't notice it on the freeways or interstates but around town. Like 3rd gear at 40-45MPH. I'll hit my throttle lock and my speed moves around like it "might" be missing.

Mileage seems to have fallen off a little. with my TFI set at 2:45 and 5:30 1st and 2nd pot I've managed to sneek into the 40's for MPG's if I don't speed much.

Last 2 tankfuls and not speeding I've got 36MPG's. This happens to be the time I "think" I've noticed this slight surging.

Before I rack too many unused brain cells has anyone here had this malady and found a simple fix? Hoses are all fine, checked them all. Bike accelerates hard wide open. Can still hit 110 if I really tried but I don't. Wide open she runs free...

Wondering if it's something in the gas? Pulled my plugs and they look perfect. they are original plugs but no need to change them when they are this clean.

Thought about turning my #1 pot to 3:30 like I used to have it when I was running regular fuel but that seems like it would crush my mileage more... I'm confused.

Air cleaner is clean. Injectors cleaned. ::)

[Cajunrider]

Brad, I agree with your thought of bumping up pot #1 maybe to 3:00 to see if it helps. Your symptoms are similar to my Nomad's before installing the TFI. Have you run any Sea Foam or MMO lately. Maybe give that a try also.

[blowndodge]

Done all that Mitch.......

[ringadingh]

My bike was doing something very similar up until a few weeks ago. It was intermittent, sometimes good for 2-3 weeks ata time.
While connecting the new gauges in my fairing I had to remove the fuel tank, and noticed the the coil wire terminal was loose were I connected the tach and cruise control wires, I replaced the connector with another one, and the bike hasn't stumbled since.

[blowndodge]

I'll go check that Ring, but you'd "think"?? that it would affect all speeds? My bike idles nice and smooth and runs great wide open. I'm thinking a loose connection would cause a slight miss across the board? ... just thinkin aloud..

[dank]

Brad, how many miles do you have on the plugs? I know you said they look good. I had a similar symptom of slight surging and mpg had dropped off. Didn't associate it with plugs. Checked mine at 36,000 miles. They looked good, clean, gaps were good, but I decided to go ahead and change them before a big trip I was taking. Surging went away. Motor ran with a new smoothness, and my mpg went up by 3.

Last month I changed the plugs on my ST at 19,000 because I had decided to not wait as long this time. Once again they looked good and gaps were fine. Difference wasn't as noticeable as on the Nomad at 36,000 miles, but my mpg went back up to what it had been at earlier.

Again, though, I am not sure how many miles you have on it, based on your other posts it sounds like you are in the mid-20's. That's plenty for the first set of plugs. thank them for their faithful service and retire them.

[rewindgy]

Probably this is not what it is but I found my throttle cable was a little sticky ( had'nt lubed in a while) and it was slightly pulling on the throttle arm at the TPS. There was slack at the hand throttle but not at the EFI body - gave it some wonder oil and it stopped the surging! Just for sh-ts and giggles I tried something ( when it works fine - just give slightly engage the throttle at idle - don;t make it rev just some pressure - you should notice that the engine will start to surge - back it off and it clears right up.

[blowndodge]

dank, 20K on the plugs...

I'd thought about changing them and spending extra to try the "Iridium" NGK plugs that lots have claimed to work real well in their bikes but haven't done it yet.

Rewindgy, I too have slack in the throttle cable at the grip but if you look at how the TPS is hooked up with the throttle you'll see that all the slack in the world wouldn't take the TPS out of sync with the injectors... I've adjusted that TPS many times before giving up and just buying a TFI !!!

[dank]

Originally Posted by Blowndodge "Darksider"

dank, 20K on the plugs...

Change them. Whether or not they are the problem, it is time, it's easy, and I think some or all of your problems will disappear.

[Dave]

This may be a dumb question but with the TFI does the spark plug gap stay the same as without?

[blowndodge]

Yes Dave...

[lonewolf]

did ya fuel up anywhere different ?? on way to sturgis got some bad gas, made bike run like crap til it was gone .

[markpenn1]

Just a thought; main ground and or battery just starting to go south can cause some weird issues. Have heard many issues as hesitations; surges; radio fade;etc.; etc; because of grounds; but mostly batteries. And at different loads; speeds; turns; etc.. However this was mostly on a wing forum. Traveling with a Harley dude one time and his speedo started going back-wards, because his battery just died. We had just left getting gas and it started just fine and then 10 miles down the road; whamo; battery dead!! These electronic driven scooters/devices do some weird stuff without proper voltage/current.

[dank]

Maybe it's just that powerful, fast car tire occasionally out accelerating the engine and then having to wait for the motor to catch up. But parsimony says change your plugs.

[blowndodge]

battery is fairly new and connectors are all clean and tight..