Sorry to post another question about suspension but I have read some threads and I am struggling to grasp this subject (being stupid I know.) At least 50% of the time I have my wife on the back, she weighs about 10 stone. Should I just leave at factory setting or increase pre-load on rear so sag is better? Iím just a little confused; any advice would be appreciated. Once I get it set for both of us on the bike then I guess the bike will be set up incorrectly when Iím on my own? Donít get me wrong, Iím not the world's best rider so Iím thinking a general setting would be good enough. Thank you in advance.
I had to Google what 10 stones was in pounds since that's how my Texas mind works. So your wife is about 140lbs. You don't say how much YOU weigh, so we only have half the equation. Assume the bike, at 'factory' settings is 'good' for a 160lb rider and you are about that. When you put your wife on, you two eat up most of the suspension travel (more so in the back), throwing off the steering geometry of the bike, and the ride is rougher for you both as the bike 'bottoms-out' the rear suspension at times. (The front is affected, too, but not as bad; you would mostly notice the front being too soft when braking, but the same principles apply.)
You need to dial in more preload, front and rear. What you are searching for is the best compromise so you don't have to keep changing it back and forth. I'd go to 3/4 of full preload front and rear and try that. It might be a little too soft with her on the bike, BUT LIVABLE, and it might be a bit too stiff with you on the bike alone, BUT LIVABLE, and that's what you're looking for. I've found such a compromise setting on many of my bikes. Just know that when your wife is on the back, don't ride aggressively. Be chill and save the 'fast' runs for when it is just you in the saddle.
Another thought is to increase the front COMPRESSION dampening about a 1/4 turn, also, so you don't blow through the travel up there too quickly when she is on the bike with you. Just experiment and you'll find the happy compromise setting that will work. Good luck.