[Nitro]

I'm wondering if you guys ever experienced your RC jerking or maybe a better term sputtering even when the trottle is in constant speed. Since I'm the 2nd owner and since I bought the bike, I notice my RC jerk or sputtering a lot especially if I'm on a lower RPM, even with the correct gears. I've been riding sportbikes for many years and went thru many bikes but I never encountered this kind of sputtering, so I'll say it is not me at all. Thou, this is my first V-Twin sportbikes, most my bikes before were Inline-4. Anyway, the worst is when I'm in a lower gear like 2nd or 3rd even with the right amount of speed. Unless if it's design like that since the torque is in low-mid range? Any ideas what's goin on???

Oh btw, I also notice my bike ran smooth (no jerking or sputtering) when I'm on the mountain twisty. But then when I come down then it will start the jerking again. Also, on a hot weather, the bike will just jerk or sputtering again!

 

[Nitro]

Forgot to add from my previous thread, my bike is pure stock, no modification as far as the 1st owner. I only added a slip-on exhaust. But the sputtering is already exist before I added the slip-on.

 

[jgos929]

I don't know if we're talking about the same thing but my bike jerked real bad in the lower rpm's really anything below 4K. Then I changed the gearing and it doesn't do it anymore.

 

[CORRELL1000]

sounds like a fueling problem if it ran fine at elevation........

 

[SubSailor]

Well first off, RC51's don't particularly like to be lugged around.
I know mine doesn't like me much at 3000-3500 RPM with lightly cracked throttle in 2nd or 3rd gear when behind cars in traffic.

And frankly, I feel sorry for it too.
Like a thoroughbred, they love to run.
If I run mine at 4000 or above, it runs fine.

Is the reason the bike no longer exhibits the behavior in the mountains due to the engine being under more load than on level terrain?

What year is your bike?
The SP1's had 4-hole injectors that might cause fueling issues at low RPMs.
That's why Honda went to 12-hole injectors on the SP2s to try and atomize the fuel better.
Under more throttle, either bike should run fine.

 

[Leadfinger]

IMHO, it is probably the tune. That would explain the change in performance at elevation and temp differences. Many people will get a pipe and you need a new tune usually after that, and the problem largely goes away. Most RC-51’s exhibit these problems stock from what I hear and I can see how. There are differences in the SP-2's that will help in that area also as mentioned. A chain conversion will help too. That will keep it from wanting to load up and lug as much. Good luck and don't get discouraged. They do not all run that way and it can be fixed pretty easily.

 

[sr2-e]

Fuel-air-mixture is too fatly the voted of Honda.
With the right Map to the Powercomander is then OK.

Das Kraftstoff Luft Gemisch ist von Honda zu fett gewählt .
Mit einem Powercomander und einer richtig abgestimmten Map ist es weg.

 

[Leadfinger]

That looks like a good board, sr2-e. VTR1000.de Germany Forum

 

[jgos929]

Pc3 will help tremendously!!! Best $250 you'll ever spend on your bike anyways.

Yo Lead you not talkin to me no more bro???

 

[Nitro]

Thanks for all the inputs/suggestions! I'm humbled to hear all your inputs. Anyway, the bike is 2005. I think all that problems you guys indicated make a lot of sense and surely it can be one of those item. For example, the cause of the problems (sputtering/jerking) indicated by JGOS929I, and SubSailor are pretty close to what I'm suspecting. Then I started thinking maybe I need PC3 to have it tune right or check the Fuel line suggested by SR2-E. Correll1000, and Leadfinger. However, I started questioning myself like since the bike is stock and no modification per the 1st owner, then why it is acting like this? So, I'll check your suggestions and hope to fix the problems. I'll keep you guys posted. Thanks again guys!

 

[Leadfinger]

No. I don't talk to anyone. Thanks. =)

 

[jgos929]

????????????

 

[sr2-e]

With 13,1-12,9 Air Fuel it is better.
If too lean, then very aggressive the gas assumption.

Mit 13,1-12,9 Air-Fuel ist es besser.
Wenn zu mager, dann sehr agressiv die Gasannahme.

 

[SubSailor]

With 13,1-12,9 Air Fuel it is better.
If too lean, then very aggressive the gas assumption.

Mit 13,1-12,9 Air-Fuel ist es besser.
Wenn zu mager, dann sehr agressiv die Gasannahme.

Correct. I believe most Dynojet centers try for 13.2:1 air/fuel ratio as that is suppose to be optimal.

 

[sr2-e]

The best is, brought it with a WBC on the street .

Mit einer WBC auf der Strasse eingefahren ist das beste.

 

[sr2-e]

The bike has more performance and less petrol consumption.
The Air RAM effect is not available on the test bed.


Dabei hat das bike mehr Leistung und weniger Benzin Verbrauch.
Auf dem Prüfstand ist der Air Ram effekt nicht Vorhanden.

 

[Leadfinger]

I need to plug in my PC3 to my computer and install the software to see what tuning and datalogging I can do. I do not have a laptop with serial so it is a PITA. I need to get a PC serial card.

 

[sr2-e]

there are adapters serially to USB.
es gibt Adapter mit seriel zu USB.

 

[sr2-e]

but not everyone works properly.
Aber nicht alle funktionieren richtig.

 

[sr2-e]

here my adapters serially