bike wont rev past 3500rpm!

[bradsegee]

hey guys
I have cleaned my carbs well (tho the need to be re-jetted because I put pod filters on) but even before that the bike wont rev above 3500. It just sputters. like its not getting fuel. It sometimes will rev above 3500 but there is a major dead spot between 3500 and 5500 rmp. Any ideas on what this could be.

[IanDMacDonald]

Tons of ideas, and tons of threads on it. Fuel/Air, spark, compression. I always assume electrical before mechanical. So, knowing the electrical system on these bikes more & more as I read and contribute, first things to check are:

1 Pickup coil wires. Remove left-hand ignition cover and slightly tug on the pickup wires. Ohm check them.

2 Spark plugs & wires.

3 TCI solder joints

4 Thorough cleaning of carbs per site standards

5 Sync and mixture settings set properly.

6 Cheap pods? Intake bell blocked?

7 Mufflers blocked?

8 Proper jetting?

9 Gas tank cap filter dirty?

10 Petcock filter towers dirty?

Number one and six stand-out for me.

[motoman]

Likely got secondary ignition issues(pick-up coil wires, weak coil input voltages, failing coils,etc.). "carbs cleaned" can mean alot of different things. Were emulsion tubes, all jets removed prior to "cleaning", float levels(8) verified correct and all identcally the same height?

Best to get running properly having stock intake before changing things.

[DGXSER]

So, did it run well at all since you have owned it? Changing to POD filters alone often will not require rejetting.

Are the POD filters the EMGO or other economy type? Some of those have a lip on the rubber that seats in the inlet bell. That lip can block off portions of the air vents and air jets in the inlet bell. That will cause very poor performance.

When it stumbles is it like running out of gas? Or more like a bad miss. If it is running well at lower revs and only shows the issue at higher revs it probably is not coils or TCI. Try running it in that mid range where it loses power for a half mile or so. Then check if all the headers are hot, and check plug color. If it is pickup coils,

I would make sure you got the floats at the right height. Also check the needle clip position, start with it centered.

[mikubuilder]

Seems like symptoms of float levels to me , probably set to brass type height. ..my 2 cents

[bradsegee]

thanks guys, I'll try those things and see what happens. the needles are on the highest setting. The fella at the bike shop where I bought the bike said to raise them up if I was going to put pod filters on. but the bike was doing the same strange things then, and it was 100% stock at the time.

[mack]

carbs

I have a set of "clean" carbs, stocfk for an SF and a stock air box I will send you for diagnostic purposes. Try them and see if you still have an issue. If so then you've ruled out carbs and pods. PM me if your interested.

[BA80]

I'm with Ian, I think it's ignition possibly the pods. Take the pods off and see if it makes a difference. If not, check the pickup wires for breakage, vacuum advance for proper operation, and the centrifugal advance for proper operation.

[DGXSER]

So prior to putting on POD filters, it was doing the same thing?

Here is a guide to tuning these types of carbs...see if any of this helps you sort it out. I would suggest you go back to stock air box and figure this out before Moving on to POD filters.