Intro: How to Fix Unstable Motorbike Saddle
I ride a Yamaha XJ6 and bought it with a Bagster comfort saddle.
All is good for me but my passenger complains about being improperly seated, so I investigated and find the issue. This is how I fixed it.
Step 1: Issues and Causes
What is the problem?
- my passenger is not seated well (the saddle seems tilts left)
- there is a lateral movement
For this saddle I found different potential causes:
- there is some looseness in the latch
- the section of the cylinder guide is too different from the hole (looseness here too)
- rivets are not holding enough
- the plastic is to soft (crack, rivet leakage)
- there is a lack of supports on sides
Step 2: Increase the Support Surface: Bridge
I built a "bridge" to make the saddle more stable with more support. 3mm steel and a reinforcement plate on the other side of the plastic.
To put them in place I needed to strip the cover of the saddle and remove all rivets. I put my plate inside, put the bridge (in the good way!) and use bolts instead of rivets. The sandwich metal-plastic-metal is super stable now.
Step 3: Increase the Support Surface: Pads
The original pads are much tough, you can see a picture of the original saddle.
Instead of change mines I prefered add some. But to check if I'm in a good way I painted the pads and seat on the saddle to see how the weight is distributed. Unsurprisingly the left side support more than the right (I take care put the bike straight, not on its crutch and I did this before added the "bridge" support). Existing screws are a good place to put these pads.
I replaced screws by head bolts screws.
Step 4: Increase Guide Diameter
Luckily the guide diameter is the same as a copper plumbing tube. A saw cut, a quick milling and 2 hits of mallet and this part is done.
Step 5: Reduce Lock Looseness
I added some washer to get down the lock. That removed the looseness, but I have to handle it carefully or it won't close properly.
Step 6: Finishing
To avoid any scratch I added a thick rubber piece fixed with adhesive tape and cable tie.
I hope this instructable help you in any way. See you!