Wobbles on uneven surfaces

[the_sandman]

I hope someone can help me with this.

I noticed my Shiver tends to wobble when the bike goes over uneven road surfaces and bumps. It is especially noticeable when the bike is leaned over, even a little. When I hit the bump, first the head shakes a little and then the back wobbles. The bike quickly recovers frm this momentary shake but my confidence takes more time to recover

On my Yamaha 150cc and formerly on a KLR650 i didnt experience this as much. Is it possible that my suspension needs adjustment and the front forks may need a checkup? Or maybe its the tire?

Anyone else on Shivers experienced this before?

[aalegado]

Originally Posted by the_sandman

I noticed my Shiver tends to wobble when the bike goes over uneven road surfaces and bumps. It is especially noticeable when the bike is leaned over, even a little. When I hit the bump, first the head shakes a little and then the back wobbles. The bike quickly recovers frm this momentary shake but my confidence takes more time to recover

Has it always handled this way for you? Does it happen at all speeds? Low speed only, etc. Does it behave the same way for another person riding your bike (rider weight is a factor when evaluating suspension behavior)?

I wonder if you need to soften your suspension. The Shiver's front suspension being non-adjustable you might have to spend some $$$ to find a fix there. On other bikes, alternatives to using adjustable suspension components is to change springs, valving, and/or the fork oil (higher/lower viscosity).

You can lower the pre-load on your rear suspension by dialing the limiters forward/upward so that the spring relaxes.

YMMV. I am not a suspension mechanic so check with someone who does this for a living.

[the_sandman]

Actually, I bought the bike 2nd hand off another guy about 3 weeks back. It is exactly a year old as we speak and has clocked 16000km on the odometer.

I'm about 80kg and the previous rider says he's much heavier than me and had the back suspension adjusted to suit his weight. So it should already be a bit too stiff for me but ironically, I like the current feel of a hard rear end.

I tried checking the tire pressure yesterday and noticed front had too little (27 psi) and the rear too much (39 psi). I adjusted them to 32psi front and 36psi rear. Improvements in handling were noticeable.

A mate of mine suggested the same thing you did, which is to stiffen the front suspension as we think it could be too soft. I might try with changing to higher fork oil viscosity first as that requires the least amount of $$$ .

[aalegado]

Originally Posted by the_sandman

A mate of mine suggested the same thing you did, which is to stiffen the front suspension as we think it could be too soft. I might try with changing to higher fork oil viscosity first as that requires the least amount of $$$ .

I actually said that I thought you might need to soften the suspension because it sounds too stiff. It also might be unbalanced, i.e. front is too stiff, back is too soft or, more likely, the front is soft (or stock) and the back is too stiff.

If the previous owner cranked up the preload on the rear (a heavier person would do that), you need to back it off since you're lighter than he is.

Good catch on the air pressure: That makes a huge difference as you have found. Coming from dual-sports, I'm used to running a bit on the soft side but street bikes with proper street tires need to run at full pressure.