I've had this bike for about a month now. Having a few issues...

1) At low speeds while on the brakes I'm getting a really bad vibration that seems to come up through the foot pegs (sdc mini floor boards) it just started yesterday and is kind of alarming. Does it with both brakes, and individually front and rear. Re torqued the foot pegs, no change. It feels like something somewhere is loose. Any ideas?

2) bike has a thunderheader, k&n stock replacement intake, and power commander and the guy I got the bike from said he had it dyno'd. When I first got the bike I had very minimal decel pops. Now, all of a sudden, the bike has an insaine amount of decel pops. I think I even heard a pop while I was on the gas.... thinking maybe I lost my map or something? PC has green power light. Any ideas?

3) the rebound adjusters on top of the forks are pretty much stuck. I can turn them with vice grips but I'm really messing them up when use a vice grip... any fix for that? Taking my bike in for race tech springs, gold valves, and rebuild next week.

Only thing I've done to the bike is rear shocks (racing bros) and fairing

Any help is greatly appreciated

Thanks

 

Just re torqued all the motor mount bolts... no change

 

Check to see if your exhaust is touching the bottom of the mid-control. If the engine is moving a little when you brake, could be rattling the exhaust against the bottom of your mid-control. You may have also developed an exhaust leak at the port, which would cause louder decel pops. Make sure your exhaust nuts are torqued properly or maybe even just replace the exhaust gaskets.

You shouldn't need vice-grips for the rebound adjuster. I can adjust mine easily by hand. Hopefully having them rebuilt with RaceTec internals will fix that issue.

Good luck.

 

Thanks I'll try to re torq the exhaust bolts when I get home from work. Vibration under pegs is getting worse and I'm noticing clunk going over bumps... suspecting motor mounts..

 

Bike that age needs serious attention paid to all the basics. Baseline it.

Front isolator is likely shot.
Corrosion is likely setting in here and there...
A brake rebuild (check cylinders for pitting, replace seals and hoses) is probably in order.
All bearings and bushings should be checked and greased or replaced (neck, wheels, forks, swingarm etc.).
All rubber and plastic bits should be inspected for cracking/brittleness.
How old are the tires?
Check the rims for straightness.
Change ALL fluids and filters. (brakes, forks, engine, trans, primary)
Check and correct alignment
etc.

 

Bad motor mounts will definitely cause wobbles. So will loose neck bearing. To check for intake leak buy some break cleaner and spray a little around the intake flange on head. If there's a leak it will start to bog down. FXDX are nice bikes. Definitely take the time like cggorman said. I'm sure you'll find a couple issues. Small issues tend to compound. Loose neck with bad front motor mount and bike out of alignment can easly become death wobbles at low speeds and high speeds just death.

 

Once the rattle/vibration occurs all the time, it will be easy to figure it out. The occasional vibrations are the hardest to fix.

Exhaust pops are from air getting in the pipe. That would be loose or missing header flange nuts, or...thunder headers tend to get cracks where the 2 pipes join into one. I have to weld mine up every 6 months or so. Popping gets worse as the cracks get longer.

What year is yours? The early FXDX's have the non-internally balanced motors, so they vibrate naturally a good bit.

 

All TC and Evo Dynas don't have counter-balancers..

 

I would guess the exhaust cracked someplace..
The rebound adjustment o ring is likely dry and never been adjusted... A little wd40 around the adjuster should help..