Hey, thanks for ur help guys. I did posted a thread about performance and I did lowered the gear like some people suggested and it is going great!! I do like it more than before now. I have a small question. I have a 2004 RC51 nicky edition. I changed the spurkplugs, chain, sprockets, air filter, and oil as well, and it runs good, but when I be riding the bike at 15 or 20 or 25 speed. the bike shake in a weird way like its gonna die on me!!!!! is that normal?? or there is something wrong? cus I noticed that couple days ago when I was stuck in a rush hour! i was riding 20 and it was shaking weird till i give it more speed to 30 or 35 to stop shaking and goes normally!?

thanks for help guys :D

I have an 03 with stock gearing and my bike does that too. I think it's just a matter of having a twin and the bike being geard high in first gear. I'm relatively new to the RC so I find myself constantly searching for gears..

mine was doing the same thing. is the clutch completly disengaged when this is happening?if not, change your fluid. Also when you put new filters in did they reguire you to adjust the air/fuel? Do you have a power commander? Did you put the recomended spark plugs in and did you gap them correctly?

I didnt even touch the clutch when I am riding 20
and change what fluid and filter? yes I do have power commander 3 and the dealer put the sparkplugs for me so I guess they put the recommended ones

air filter is K&N and I put it couple weeks ago. the clutch and front break oil looks on the streering are red like new! and they didnt tell me anything else..

I've found that anytime you get below 3500 RPM, you can get into a engine lurch situation.
Usually a combination of two large pistons, two very large throttle bodies, drive line slop, and sensitive fuel injection, and much lighter flywheels than a Harley.
I've got 15/41 and I find it hard to even do 35 MPH in 1st gear without the bike acting up. At 4000 RPM, no problem.

The fact that it runs relatively well at all with dual 62mm throttle bodies at low RPM is a wonder of modern fuel injection.
Try this with dual 62mm carbs at 3000-3500 RPM and it will give you a whole new definition of the word driveability (not).

The RC just isn't happy at low RPMs, which is one of the benefits of re-gearing, less time trying to ride around under 3k. K&Ns shouldn't really change anything, but finding out what PC3 map you're using is useful. What exhaust system?

I am usuing yoshi stainless! and its V-twins tho
subsailor, can u explain more what should i do? I kinda got lost lol

RC's are definatly not happy chugging below 3k rpm. It took some getting used to for me coming off 15yrs of I4's

so you guys think thats normal?? and nothing wrong with the bike at all?

Don't think so from what you're describing. Just try not to lug the motor down.

A gearing change should have helped that out a lot. You said you changed the gearing? What did you go with?

15/41, and it does the same with 16/40 the normal stock too!
it shake like its gonna die, like when u go out or fuel and the bike shaking front and back LOL

It's the nature of the beast.
I used to have an old Buell X-1 (fuel injected) that had both cylinders breathing through only one throttle body that was smaller than on the RC51.
And it would snort and backfire through the intake in better riding conditions than the RC51 puts up with.
Compared to it, the RC51 is very mild mannered for such a state of tune.
With 8 years of development, Ducati's FI systems on their monsters and 1198's is amazing.
If Honda had persisted with development (we wish), no doubt it would be just as refined.

yep!! i think thats normal for the RC51 tho. good thing its normal so I dont have to worry about it

I have heard it is normal a lot!

On mine I can let the clutch out in first gear until the bike is moving, not add throttle, shift into second gear without adding throttle and the bike still chuggs along, no surging. I can cruise in second gear at idle with no throttle input.

If I add throttle the bike accelerates, no surging.

You're lugging the motor.
Don't do that.

I didnt even touch the clutch when I am riding 20
and change what fluid and filter? yes I do have power commander 3 and the dealer put the sparkplugs for me so I guess they put the recommended ones

air filter is K&N and I put it couple weeks ago. the clutch and front break oil looks on the streering are red like new! and they didnt tell me anything else..