Bike sputters a little bit on hot days

[BB1000]

mines doing the same thing ... have checked vacuum hoses .... bloody bike

[TexasFly]

Mine does the same thing. For the record - it's a 2007 that was un-crated last April. Has 3100 miles (5000kms). Leo Vince slip-ons, Map2. I won't have a chance to check on hoses for a while, but I'll keep checking this thread to see if there is any resolve. I'd be surprised if there are bad hoses on a bike that only has 3100 miles. Granted they're 5 yrs old, but they weren't subjected to any engine heat or other abuse until this time last year.

Mine is 2008 configured as yours and, every once in a while, when the engine is fully warmed up, it "bucks" under a steady throttle - much like a misfire or a momentary lack of fuel. It can be a bit unerving if you are not expecting. I will be following this with much interest ..

[Galaxian]

Alright,
Not running I got 11.3 and running when warmed up was 13.5.

Was this checked at the battery, with a good meter or using the dash readout? These values are a bit on the low side if it was measured at the battery.

[ride10]

Mine ONLY happens at ~4000 rpms (when warm only). And when holding steady on the highway. If I'm accelerating then no....never a hiccup. I'm planning to install a bazzaz next year, but I would really like this resolved for this year at least. I know at the 1000 km first service the aprilia tech said it was running lean, and to put the baffles in the exhaust. I did that....and overall things improved a bit, but still has the 4000 rpm hiccup.

[ecan]

Fuel pump...my tuono had the same symptoms. Just replaced the fuel pump about an hour ago......took it for a ride in very slow traffic so the engine would get good and hot. Seems to run like a champ now. The true test will be this weekend on my way to Road America.

[lanes luck]

I just replaced my fuel pump too, still runs weird at 4000rpm.

[asb2106]

Fuel pump...my tuono had the same symptoms. Just replaced the fuel pump about an hour ago......took it for a ride in very slow traffic so the engine would get good and hot. Seems to run like a champ now. The true test will be this weekend on my way to Road America.

I didnt see any Tuono's there!!?!

Bummer I was looking hard too. Seen a nice RSV4, an 07+ RSVR, and a blue and yellow RSV Mille, on top of my factory Better Aprilia turnout than last year!

**OP

Could be the fuel lines on the pump in the tank. I had that same issue on mine for about.. ten minutes, then i just completely shut off. No more. Thank goodness i was only a couple blocks from home.

The fuel lines had cracked and come disconnected from the fuel reservoir in the bottom of the fuel sending unit. Replaced the lines, replaced the hose clamps, and all better.

could just be a small crack in the hose maybe pulling in air from time to time causing a miss? I know its a guess out of left field, but it never hurts to check those hoses anyways. Especially if they have never been replaced.

[ride10]

I'm going to check it all over as soon as I get the chance....but that won't be for a while yet. I'll post up if I find anything.

[Wharewolf]

Was this checked at the battery, with a good meter or using the dash readout? These values are a bit on the low side if it was measured at the battery.

This was check on bike display

[Wharewolf]

Mine ONLY happens at ~4000 rpms (when warm only). And when holding steady on the highway. If I'm accelerating then no....never a hiccup. I'm planning to install a bazzaz next year, but I would really like this resolved for this year at least. I know at the 1000 km first service the aprilia tech said it was running lean, and to put the baffles in the exhaust. I did that....and overall things improved a bit, but still has the 4000 rpm hiccup.

I think that is what we should officially call it " the 4000 RPM hiccup"

[Wharewolf]

Got a brake from the hundred degree weather yesterday and just like in the winter the hiccup went away maybe to do with the air temp

[ecan]

I didnt see any Tuono's there!!?!

Bummer I was looking hard too. Seen a nice RSV4, an 07+ RSVR, and a blue and yellow RSV Mille, on top of my factory Better Aprilia turnout than last year!

**OP

Could be the fuel lines on the pump in the tank. I had that same issue on mine for about.. ten minutes, then i just completely shut off. No more. Thank goodness i was only a couple blocks from home.

The fuel lines had cracked and come disconnected from the fuel reservoir in the bottom of the fuel sending unit. Replaced the lines, replaced the hose clamps, and all better.

could just be a small crack in the hose maybe pulling in air from time to time causing a miss? I know its a guess out of left field, but it never hurts to check those hoses anyways. Especially if they have never been replaced.

Oh yeah I was there with another Tuono. I only saw one other tuoldo and a Black RSVR riding around. The bike ran great all the way out there and back. Now it is acting up again and the only thing left is the stator. I'm really starting to get sick of this thing.

[ride10]

Bump. Anyone had any success in solving the 4000rpm hiccup issue? I was hoping someone posted saying that it was as simple as a bad vacuum line. I myself want to install a bazzaz, but I'd really hate to go to all the expense to find the hiccup remains....

[Wharewolf]

It's wierd, only when it's hot out, last summer it started, then winter did not do it, and now again. Have anyone else noticed that?

[ride10]

Has anyone here that has the 4000rpm hiccup removed the charcoal canister? I just had my bike serviced today (props to Gord at Valley Yamaha by the way). As a matter of course, they removed the charcoal canister, which was on my list of things to do anyway. Gord explained what it does...but the only thing I think I heard was "...it makes the bike do stupid things when running hot". Well...it was hot today, and the whole ride home (1 hour) I tried to see if the hiccup remained. It seems to be gone. I can't say for sure until I ride some more, but good first run. Plus....the tank doesn't blast me with fuel vapour when I open the filler cap anymore. I should've removed that canister ages ago.