Ok this is the second year that I have had my "new to me" 92 fxrs-sp
I took it out over the weekend and while I was riding, somewhere between the 2000-3500 rpm range in any gear I would get this weird jerking feeling. The rpms didnt move up or down and it didnt seem like i was loseing speed or gaining speed.

I was thinking clutch? or belt?

I did put new plugs, wires and air filter in during the winter.

Any help ? please ....

 

Possibly your primary chain needs adjustment.
Are the new wires firmly seated on the plugs and coil? Plugs tight enough, not backing out?

 

Too lean?

 

The wires are on tight.

Also I just noticed this.
I took it for a ride just now and when i was in 3rd gear I really got on it and go it up to about 3500 rpm and between that and 4500 the bike didnt increase speed at all.. Is this a clutch problem ?

Is that causing this jerking feeling? like slipping or something?

 

primary chain

 

Sounds more like the tension of your primary chain needs to be adjusted.

 

I agree with the others.....check the primary chain. It sounds like it needs tightened....but not too tight. A little on the loose side is better than a little on the too tight side.

 

Thanks !

I will let you all know what happens when I check the chain.

 

Slipping clutch and/or spring plate coming apart in the clutch pack would be my guess. Certainly primary chain should be checked. And especially since it's "new" do at least a quick check of the wheel bearings. If one is going out, they'll make it seem like it's dragging like a brake, then roll freely. Not quite an abrupt jerk, but like someone grabbing your fender slowing you down then turning loose. Noises and "feel" are hard to communicate/diagnose online.

Never had a BT 5 speed give much trouble, but had a Sportster once that had an ocassional abrupt hard jerk at any speed. Wasn't noisy but would definitely get your attention. It had 2 bad gears in the trans...

 

It has to be the clutch. The chain or belt would have to be really loose to slip. Since you can increase rpm without any speed increase, I would think the clutch is slipping. Adjust your clutch and see if that helps. Oh! One other thing, would the compensator do this? Can they slip if they are loose? Just my thoughts.