Modern Buddy

So i still have the issue of the backfiring and sputtering with no power (mostly under load; up hill). I cannot seem to pinpoint the issue and the engine lite never has gone on. One thing that seems to help is the gas...all 93 octane but certian stations seem to have different results? Now another clue just surfaced...the idle has increase so much it almost engages the trans. Is there some kind of idle sensor or something that could be the culprit? Has about 2500 miles on it (I bought last yr with 300). Altho I fear breaking down, when it runs good it is GREAT!! The exhaust has no soot, is white and clean looking. I stopped over filling it and also disconnect the house coming out of the tank to see if it is vape locking. Open for other suggestions to try...

I own the exact same year, color and model Buddys and I'm also in NJ. What a coincidence!

Nice catch...I'm way up north; you?

Do youhave any issues with the 170i?

I think psymple and giddyup98 are the same person with a personality disorder. Lol, just kidding.

Have you looked at the sparkplug color to see if the engine is running lean? It should be a tan color and not white. The symptoms you're describing sounds like the engine might be running lean due to an air leak.

Hmmm, an air leak is something i hadn't considered. When I first got it a chipmunk had eaten the air intake tube and filled the air filter with a seasons worth of grub. I cleaned it out and replaced the tube and hadn't seen any other damage. I hadn't had any issues until this season however. I'll have to look again closer. This issue comes and goes however.

One time, I had met someone for lunch 20 miles away; driving home i had to pull over to relieve myself and only turn the toggle switch off. When I resumed, it was acting up. I stopped and turn the switch and key off and then in reverse order, back on and it ran fine. I thought electric but this hasn't helped again...just coincidence I guess.

Why would the idle pick up suddenly and drastically?

No issues with my 170i. I'm in northwestern NJ near Hackettstown.

psymple wrote:Nice catch...I'm way up north; you?

Do youhave any issues with the 170i?

Two questions:
When is the last time you replaced your spark plug,
Have you done anything involving disconnecting the battery recently? Throttle position sensor is usually my first go-to with the 170.

Also, how many miles are on the bike? You might be getting due for a valve adjustment, though admittedly that would be a steady noise/loss of power rather than an erratic symptom.

there are only 2500 miles on it (bought last yr with only 300) I checked the plug not too long ago. I put the bat tin in the beginning of the season and it pretty much started right away (2 tank full I believe).
I do hear the valves so they are a lil loose. I order the feeler gauge, hope it arrives tomorro so I can adjust this weekend. The symptoms are a bit erratic so I'm hoping that helps. Even when it runs strong, it pops and sputters out the exhaust. The bike runs REAL strong except when....
If that doesn't help, I may try to replace throttle sensor...thanks for that tip.

Have you tried resetting the throttle sensor? If not, try that first. The sensor itself hardly ever goes bad, and especially not on this low-mileage a bike.

In 8,000 miles and two valve checks on my 170i, I never had a loose valve. Intake stayed put. Exhaust was tight both times. Good idea to check them.

I would first try resetting the ECU. This, as mentioned above may reset the sensor.

I did not try to reset the throttle sensor (nor have I looked into it), do I need a scanner to do so? If not is it straight forward?

This morning it struggled to make it over the mountain both ways. On the way back, i thought it was running awesome...until... It is so sporadic

As soon as the feeler gauge gets here, the valves are getting checked..I hope it arrives today for tomorrows project.

despite the trouble, she can't break my love for my Buddy['s]

Thanks for all the input peeps!!

OK, here's the update.

I first filled it with the gas I thought would make a difference...nada

I second disconnected the neg from the batt for a few hours...reset the ECU and throttle sensor?
No change

I then adjusted the valves. they were loose . They are quieter and there is less popping. It still struggles on the mountain!! I also looked for air leaks, none found.

Also...now there is a dead spot in the idle; still fast but it cuts out at intervals. WTF could this be?

Whenever I get unexplained cutting out or intermittent power problems, I immediately suspect a failing stator.

People usually chase their tails checking the fuel side when the problem is on the electrical side.

It's worth checking into.

Here's what the plug looked like...

Since I was tinkering, added the bar end mirrors..

Plugs looks good....nice chocolate brown color.