Hey, I'm currently on my first multi day trip with the new bike. I also did set it up tubeless currently. Now that it's loaded I'm having this bit annoying thing with wobbly front wheel. See the video. I set the tire pressure according to Wolftooth calculator. So having front ca 20psi, rear 22psi. Even if I'm just shaking the bike side to side it wobbles on both tires. Tires are WTB Ranger 2.6. So wobble is there also in the back but it's most prominent when I want to ride without hands. Is that normal? Or should I add more pressure or is my weight distribution wrong? There's also photo of the bike in first comment, a bit more weight on the rear than in the front but I would call it balanced. I know having full front rack from my gavel bike but it was never so shaky. I guess because of 47m tires.
Thanks ahead!
by macm65
26 Comments
https://preview.redd.it/x3b9n8la97ug1.jpeg?width=3936&format=pjpg&auto=webp&s=faab763a560050055f4609e506aebd1f768a28ca
Here my setup
Try removing all the bags and test that way to troubleshoot.
Have the rims been trued
Weight in front of the fork like that will tend to pull the handlebars/fork sideways, leading to wobble at higher speeds. Stiffer frames/forks help to some extent. I will bet it would go away if you move the bags from the front rack to the rear. The bags directly on the fork are already behind the axis, those should be fine.
I have similar when set up that way. It’s a prime storage area for me so I just deal with it.
Normal.
Cane creek visco headset can help
A couple things: see if the fork bags are similar weights, and even out the weight if you can. Make sure your heaviest items are as low to the ground as possible, such as in the bottom of the frame bag. Try to find a lower positioning for your front rack, it reall looks like it’s riding high.Weight sitting too high will introduce instability.
Wobbles like that can be dangerous, especially a high speeds, or on uneven terrain.
How heavy is the stuff sack that’s furthest out in the front rack? I’d be curious if anything changes if you remove that or even stack it on top of the red one closest to the handlebars.
Speed wobbles
Leaning back taking weight off the front causes that also.
Change bags on the fork legs going forward instead of back. It puts the weight over the axle instead of acting like a weighted rudder. Also reduces the chance of kicking the bags while you pedal.
This is [Shimmy, or Speed Wobble](https://www.sheldonbrown.com/shimmy.html).
There are a couple things you can do to try and help (without just removing all your front weight);
– if it’s occasional: rest your knee on the top tube. This reliably stops wobble, but only when you’re not pedaling
– add damping your steering: there are some spring-based dampers that may help, or a damping headset.
– change your fork: this is the most reliable. A fork with different trail (offset) will handle this differently, typically lower trail will help. But any change to your fork will make a change.
– change your bag loading: this is probably the easiest. Placing your load lower should help, reducing the amount of weight will help.
As always, Saint Sheldon has the details…
OP I know it’s easier said than done but if you’re able to weigh out a more equal balance between the bags, it will absolutely help.
Check with the tubeless setup that the tires are properly seated. A small difference gets exaggerated under load.
Strap everything closer and tighter than you have it. You’re having speed wobble and it’s resonance related. If everything was rigid, you wouldn’t have that problem. They make e bike steering dampers, consider it if all else fails.
Your bike is concerned
I have similar on my Nordest. The fork is nice and comfortable, but it’s also very long and thin.
Look up “High Speed Shimmy” – it’s possible that it’s a loose headset but could also be the weight distribution and center of gravity. It often happens without any additional load on the bike, and in fact can happen if the fork/front wheel doesn’t have enough weight. Grabbing frame with your knees can help calm down the high speed shimmy.
Too much weight too high above steering axis
It may the case that the weight in the front is not evenly distributed between the left and right, which can create this issue. As a first step, if you have bottles on the fork, I would be sure that both are filled full.
It’s weight distribution between the bags, that’s it.
It’s most likely the way to the bags. I’ve seen several e-bike videos where they’ve had the same problem and switched to a Cane Creek headset (hell Bender), which seemed to have helped quite a bit.
Cane creek visco set enters the chat…
I have similar behaviour of my bike under load, especially with more weight on the back.
What helped for me was to move more weight to the front, so it’s better distributed; evenly balance the weight left and right both frond and rear; increase tire pressure for stability and be lucky, because sometimes the wobble just isn’t there and I have no clue why.
Get forks with more rake?