After re-installing my KH T-Bar to my KH Fusion Street, I started noticing a creaking noise every time I hit a bump. It took me awhile to find the source. For some reason, this creak was coming from the stiffening plate.
To fix the creaking noise, I cut a very small piece of an old inner tube and placed it between the stiffening plate and the saddle base. Then, I tightened all of the screws. Problem fixed. I hope this helps someone.
Stiffening plate? You mean the reinforcement plate, right?
I had a creak there, just add some lubricant like grease or teflon bike lube (what I used, cleaner than grease) to the area creaking (under plate, bolts) and it’s gone.
Yes, sorry, reinforcement plate. For some reason, I had stiffening plate stuck in my head.
I thought of using a lubricant, but I thought the tube would be a more permanent fix. I just happen to have an old tube that I use for fixes just like this. That creaking noise was driving me nuts and I don’t want it coming back! 
Yeah no problem, it’s making that sound because the plate is dry rubbing on the other pieces. When I first heard it, it drove me crazy and I thought it was something more serious. It was a deja vu back to the days when I had my road bike and it had a creak. Not so bad until you’re coming home at night on a quiet street pulls hair out
I heard an inner tube is also a great way to protect your T-Bar from damages during a fall.
On my aero bars that are attached to the t-bar, I use the rubber feet that are on the ends of canes. They’re cheap and work perfectly. They’re available at any drug store for $3. I’ve used them for years on my bar ends, before I added the aero bars. The fit is pretty tight, but if one grabbed them just right, they would come off. I used to use electrical tape to help secure them to the bars, but recently I switched to using pvc irrigation glue. The glue works perfectly. I’ve had the same feet for 5 or 6 years and there isn’t even a mark on them.