Topic: Crappy RMPS continue...

[kurtanton]

Hi,

So, I cleaned the bowls, took off the tops of the carbs - the caps?- flushed the carbs  out w/ carb cleaner. Flushed the tank, cleaned the fuel cock, put it all back together, and while on the center stand it ran very smoothly, clean rpms all the way. Put it down, and I get the crappy rpms again! Same range around 4k. So I decided to take it for a ride. I can force through the rough range with some garble and chokes and the bike will move pretty quick once I am through. Since it runs well on the center stand, and crappy off, could it be something to do with the position of the floats? Level ground? uphill vs downhill? Thoughts?

Thanks,
-Kurt

[KB02]

First of all, what year & model?

You said you can force it through the crappy section? Does it run better up above a certain RPM?
Have you checked the timing and the valves for adjustment? Have you checked the timing chain?
When you cleaned out the carbs, do you physically remove the jets and check them for blockages?

I'm not sure what else to ask.

Angle (on the center stand vs. off) shouldn't make that much of a difference.

Do you have an inline fule filter? If you do, take it off and clean it out. I once torn down and essencially ruined an old snowmobile engine all because I never checked the fule line for blockages.

[TwoTired]

I'm going to make a couple of assumptions.  You're talking about the 73 CB350F in your avatar.  And, that you've made exhaust and air filter changes from stock.

Have you checked your plug deposits for deposit color?  See:
http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html

This will tell you if you are running rich or lean.

Do all the tuneup items and be absolutely certain they are spot on adjusted before mucking with the carbs:
Compression test numbers
point gap/condition
ignition timing
Spark plug gap/ condition, correct number plug
Cam chain tension
Valve tappet adjust.
Clean air filter
Carb synchronization.
pilot screw settings.

With the knowledge about these items, steps can be taken to deal with specific performance issues at noted throttle settings.  Don't gloss over the above.  Unless, you like you butt bitten. 
Cheers,

[eldar]

What rmp does this happen? That will also tell us where the problem lies.

[kurtanton]

Hi,

That's where it gets spotty, can't really work past it anymore, just slows the ride down. I notice I have some small holes/loose seems in the exhaust, would that cause it. Sometimes it is perfect, but rarely on the road, usually in the garage on the center stand...

Thanks,
-Kurt