Triumphrat

alexandercase

So yesterday I installed some factory pegs for the rear passenger that had been taken off of my Triumph Bonneville 2007, I had the girlfriend hop on the back to the grocery store and about half way there the bike started to wobble after picking up some speed from 15-35 mph. Immediately turned back home and drove real slow, not sure what it is, but it is a significant wobble that just started by having a 2nd rider...any ideas...

bonniemojo

Tire pressure?

ItsForrest

Yup, check tire pressure. Also, if you are both over about 150lbs, crank up the pre-load on the shocks.

__________________
The urge to buy terrorizes.
'08 Scrambler - work in progress...

PeteV

We can assume your alignment is good?

alexandercase

the wobble was there even after she got off the bike. if that makes any difference

milsherut

I have a tail rack (and had a box on it)...whenever I had more than a few pounds in the box (a lot less than your girlfriend), I got low speed, but tolerable wobble...nevertheless, I lost the box anyway...later at much higher speed I hit a modest pot-hole, and that caused a pretty scary wobble...I decided that was due to incorrect tire pressure (actually, too high in the front).

So I check tire pressure front and back before every serious ride and have not had a problem since...I also make sure my rubber is not more than a couple years old.

RickMcCl

The book says to set your rear pre-load at five (highest setting) when carrying a rider.

I do that when my wife's along; and have had no problems.

I also check/inflate the tires every week.

My front drops 2-3 pounds, and the rear a pound or so, so I inflate the front to 35psi, and the rear to 40psi (book calls for 33/38).

Rick

alexandercase

It is definitely the rear tire, very low, thanks for all the advice!

Anyone have any or know of any good videos on how to adjust the pre-load...?

Forchetto

Preload is adjusted by a hole in the side of the shock collar. You insert a suitable screwdriver, even the allen key supplied for seat removal, or similar implement of around 6mm diameter and turn.

Clockwise to increase pre-load. I mean clockwise as viewed from the underside of the shock.

The owners handbook has a comprehensive instructions under "rear suspension adjustment" pages 83, 84.

Triumph do make a tool, sold for around $3.00 but as you can see it's just a piece of steel rod:

alexandercase

i adjusted it to the opposite of what it was set at, wish there was a video to make sure i am setting it to what is best to ride with a passenger. I have searched youtube extensively.

So if you are looking up from underneath the bike is how they determine clockwise and counter..