does "lean stumble" develop over time

[user 31223]

i have a new , just 4k miles 2012, and thought i may have got some bad gas (not me the bike) but after reading this thread https://www.fjrforum.com/forum//index.php/topic/147559-misfire-at-steady-cruise

im beginning to think i, or the bike , have developed "lean stumble-itis"

i have put a couple of tanks worth of gas in and also added seafoam, not really made much difference.

it accellerates fine, but at 3.5k revs in 4th i get what feels like a bumpy ride.

i ordered a pc5 today as that seems like it would help.

anyway, interested in what you all thought. it is getting close to its 5k service, and had the 600 mile done at roseville yamaha, well respected service dept based on posts here.

should i try other stuff before i stalling the pc 5 or do it anyway.

thanks in advance

 

[a.droid]

Mine seems to be much smoother after the Jumper Mod. Tried that?

 

[escapefjrtist]

The '08s and up are pretty well sorted out regarding fueling issues. Lots of folks add PC's to cure what's left of perceived off idle throttle abruptness, IMO they're really not doing much other than using more fuel. I can't think of any technical reason for the bike to develop a lean stumble over time.

Barbarian mod is something to try, but you'll get many opinions as to its effectiveness. The BM definitely helped my '06 off idle. My '09 fuels great throughout the rev range so I really don't have any complaints.

Just my $.02

Good luck!

--G

 

[SkooterG]

The '08s and up are pretty well sorted out regarding fueling issues. Lots of folks add PC's to cure what's left of perceived off idle throttle abruptness, IMO they're really not doing much other than using more fuel. I can't think of any technical reason for the bike to develop a lean stumble over time.
Barbarian mod is something to try, but you'll get many opinions as to its effectiveness. The BM definitely helped my '06 off idle. My '09 fuels great throughout the rev range so I really don't have any complaints.

Just my $.02

Good luck!

--G

What that ^^^^ Fart Smeller said.

I am not a big fan of the Barbarian Jumper mod unless you are using an Exhaust Gas Analyzer to do it right. Otherwise it's just a SWAG. But your 2010 really shouldn't have any of those issues as things were pretty well sorted by 2010. Still, PCV might help. I will be interested to hear the results.

 

[LAF]

Well thinking a lean stumble could develop under the "right" circumstances. Bad gas, bad riding habits as in lugging the motor, anything that could fowl the TB plates with carbon. I am not a advocator of TB syncs cure the worlds ills, but cleaning and a sync just might.

I know my bike changes TB syncs in a very short time,like 5 0r 6 k miles. Not sure why?

I would guess valve seat issues of being carbonated could cause this also?

I run a PC V and auto tune and while I do consume more gas then most post up here I do not suffer from any lean or performance issues that I can tell.

I also would wonder of the definition of lean surge? Mine will still hunt and peck a bit at times and vary RPM a few hundred but nothing that is an issue for me. This is while stopped at idle.

Could it be heat soak?

Just something I never give a thought to as it is just "normal" to my bike and no issue. It never stalls and is always ready for the grip to get twisted and always responds like a champ.

I got a bad tank of 93 in my turbo car and it took a few tanks to really come back up to snuff. At the risk of repeating myself, Star Tron and Ring Free are your friends.

 

[user 31223]

ok thanks - as im a new rider on the FJR maybe i am guiilty of "lugging" the engine, as i had a scooter before and so am still developing my clutch skills - i will try a couple more tanks of gas and will give ring free a go - i tried seafoam but i guess ring free is different

Also the service is coming up so maybe do that a little early - I do 2-500 miles a week - so its only a week or so early

 

[Mihalis fjr]

The barbarian mode helps only at the idle circuit and max at about 1500 rpm.

Like Skooter said only if you have an Exhaust Gas Analyzer then you can adjust correctly the mixture and only in the idle..!

At 3.5k surely the barbarian mode will don't any difference!I believe also the PC5 with a good map in will resolve your trouble!

 

[Bounce]

I've liked Ringfree and Techron (which is cheaper and available at nearly any auto store). I've used Seafoam but find it less effective.

 

[Fred W]

The definition of lean surging is when riding at a steady throttle the bike feels like it is irregularly bucking, i.e. slowing down or stumbling slightly, almost as if you are running into a gusty headwind, or hitting irregularities in the road that aren't there. Some people are more or less insensitive to the phenomenon even when it is clearly there. Others find it annoying and objectionable even in lighter amounts.

This is not a unique condition to the FJR. It happens on many bikes that are delivered with intentionally lean fueling from the factory. The bike that I owned that was the very worst in this regard, and the one that has made me perhaps overly sensitive to it on any other bikes, was a 1994 BMW R1100RS. It had an early version of fuel injection installed and the fuel map was set way too lean to help it pass emissions qualification. Installing a Techlusion TFI fuel injection box, and adjusting it to add more fuel was the eventual fix.

I later had it on a 2001 Kawasaki Concours to a lesser extent. Increasing the pilot jets size was the fix there, same story with a 2001 Triumph Trophy 900. Both my 2005 FJR and 2004 V-strom had the phenomenon when I bought them. They both now run Power Commander III units and the added fuel from those devices have eliminated the surging.

The only modern fuel injected bike I've owned that doesn't have lean surging in its stock form is a '98 Honda VFR800, which is an odd type of fuel injection system that has no cats in the exhaust and no O2 sensors. I suspect they set the fueling rich enough in the stock ECU map to have avoided it.

 

[user 31223]

Fred, yep that describes what im feeling exactly - my very first thought was i should look at adjusting the front forks - but then i tested that by just dipping the clutch and coasting at highway speeds and the "stumble" diminished enormously _ the rest was true road unevenness - As i mentioned i seem to have developed a sensitivity to it and hence my "does it develop over time" question - but i must have just been so impressed with everything else on my new bike that i ignored it

- I am on my second tank of gas with Seafaom - i cant say its improved at all - so im still leaning towards the PC 5. I already had seafoam in the garage which is why i havent tried the other suggestions yet.

Appreciate all your patience with the newbie (in almost every sense) question - but i think you guys have helped me diagnose "our" (bike and me) issue - i will update the thread when i have the install done, wont arrive till monday next week so will be a couple of weeks

 

[user 31223]

Took the bike for 4k service, to Yamaha Roseville, and zac test drove it, he said it drove pretty much as he expected, I don't have the power commander on yet, wll try that next, but wanted to get a tbs done and 2nd opinion before I started messing with it.

Interesting conversation about the jerky drive after standing outside In the warm sun , he mentioned, that the charcoal, canister in the fuel system can cause this, and the fix is either disconnect the canister, as he has, , or give the bike couple of decent throttle twists before starting off.

Didn't follow that 100% but will look into it.

 

[pcarnut]

I've had very good luck getting rid of pretty much all my leanness with a tb sync and installing the PC V w/ autotune. After installing them I refined the air/fuel ratios a little with help from their one of their support guys and am very pleased with the bike now. I actually had a slight gain in fuel economy, so icing on the cake. ymmv

 

[user 31223]

I finally got round to installing the PC v today, o2 sensor disconnected, using the calculated smoothness map. Made some difference I think, not perfect , so probably need the auto tune, just couldn't afford it right now, so I' ll take the improvement or now.

On the Pc v map , the pc iii version seeme to have a ignition table, but the when converted by power commander app it caused an app error, so I had to basically copy and paste the fuel mapping, but can't do the ignition, is that going to be a problem ? Does it need an ignition map too .?

Clearly auto tune is the answer, but wondered if anybody knew ?

 

[Kc5]

I installed the PCV today, on my 2012. My bike is just about to roll 5000 miles. I don't know if it just started developing the surge, between 2500 and 3000, or I just started noticing it, but it annoyed me.

I would say it was about a 75% improvement. Trying to find a place to ride today, where there was not 35 MPH wind gusts, was a challenge. I will give it a more fair evaluation if the wind slows down.

Is it likely that a TB sync might finish smoothing things out or should I tweak the fuel maps?

Should it already need syncing at 5000 miles?

 

[escapefjrtist]

You're not going to need a TBS at 5K miles. From our experience at Tech Days, late model FJRs are rock steady in that regard.

Not likely a TB sync will do anything to smooth things out. A good map for the PCV is what you're looking for...

Good luck!

--G