Not running smooth...help please

[atago22]

Could anyone give me a suggestion what could be wrong here:

I am running my Pitbull 08 with an S&S dual intake on a XXXcarb with a 600 cam with a thunder heart ignition and bigcity thunder baffles in V&H pipes.
The bike idles fine and has whopping power when I tap the throttle however when running around 50mph in 5th gear (2000 rpm), the bike seems to be jerky like its getting insufficient fuel.
Although the rev counter does not change, I can feel it jerking underneath me.:bang:

At a loss here - any suggestions?

 

[woodbutcher]

running the 600, you may just need to downshift at that point. did you put the cam in before or after the triple X? usually they are good about setting the carb up for your situation. if you put the cam in after the carb, you probably need to re-jet.

 

[atago22]

Cam was installed after the XXX

 

[BadBrad]

Just for good measure I would take a bright light and check your tank to make sure your liner is still in tact. It's possible that you have a little trash in your tank or carb that may only show when you have low pressure fuel requirement. Did you change jets after your modifications? What jets are you running?

 

[Five Five]

Could anyone give me a suggestion what could be wrong here:

I am running my Pitbull 08 with an S&S dual intake on a XXXcarb with a 600 cam with a thunder heart ignition and bigcity thunder baffles in V&H pipes.
The bike idles fine and has whopping power when I tap the throttle however when running around 50mph in 5th gear (2000 rpm), the bike seems to be jerky like its getting insufficient fuel.
Although the rev counter does not change, I can feel it jerking underneath me.:bang:

At a loss here - any suggestions?

Thats quite a set up :up:

Is this a new problem or is this a problem in conjunction with your latest mod ?

 

[Little-Boo]

What jets are you running, if you installed the cam after you bought the Carb, you may need to up the your jetting to the next size up. I would say you should be running 31/76 at least that. Is your Thunder Heart the ajustable one and if it is what setting are you running on that. Postition 4 is about what you need. I run Posititon 6 but I am nuts and have a little more on my dog than yours.

Carlos

 

[erldawg]

Your lugging the motor. 5th gear at 50 mph is too high of a gear you should downshift. How's it run at 65 in 5th gear?



Sweet five five....

 

[V]

2000 rpms in a bit of lugging on the engine. As noted check your jetting and try running the engine in the 2500 rpm range.

 

[lee]

I agree - you're lugging it

 

[stlmikie]

Does it cough through the intake?

 

[Perro Grande]

I installed the dual runner a few weeks ago on my Mastiff, ran ok at low speeds , but when I jumped on the freeway and tried to get up to speed it ran real rough, like it was running out of gas, or something. I did some research, and found out I need to pull my bowl vent plug out of my carb., it now runs smooth!! Easy try......just takes an allen wrench, its located on the outside of the carb......if it works great, if not put it back in......Good luck

 

[Daddycool]

You are lugging the motor. Downshift and keep it above 2500 rpm. The only other thing I can think of is possibly a loose primary chain tensioner. Still think you are lugging it.

 

[PaulHart]

Yep I agree probably just lugging it. I just installed pipes, breather and a 600 cam last Tuesday. Started out with 31/78 jets and I think I'm pretty close. Mine will also lug at that RPM. 40MPH is a bitch. The Dog never liked it and doesn't now either. Downshift and run in the 3000 RPM range when that happens.

 

[AddictJ]

that cam does not like 40mph! i keep the bike about 3grand

 

[atago22]

Thanks to all....will ride at higher RPM and lower gear....

Went for a freeway ride....6th gear and 2500RPM is giving me a smooth 75 - 80 mph....

 

[johnstonad]

Hi atago22. 75 to 80 mph looks interesting numbers. I hope to see more progress for it.