Wondering if anyone else has come across this: I’m just coming over from a road set up, and got a new Argon 18 E-112, and I’m 5’ 10" and 155 lbs, training for my first IM. Bike seems great on flats and climbing, however every time I go downhill (serious downhills, not rollers), the bike seems to randomly oscilate to the point where I have to slow waaaaayyy down, and really ride my brakes down the entire way. This never happened to me on my road set up, so I’m wondering if it’s just part of a tri bike (doesn’t make sense), if it’s mechanical (wheel out of true?) or if it’s just me?
I have an aero bottle on the front, and my stem is raised about 2" from the frame of the bike. I have cages on the back, and it seems to have just started happening (400 miles on the bike so far, but nothing for the first 300 miles or so, and in the past 100 miles, it’s seeming to get worse…)
Any suggestions? Get back in the saddle more? Get forward more? Give up this sport?
Speed wobble is a horrible thing for sure. It’s probably a gamut of things, but from a first order solution, try to unweight the saddle a little bit and clamp one or both legs onto the top tube.
What you’re trying to do is knock out a resonance that has established itself. Could be from a lot of things–wheels, weight distribution, frame harmonics, a loose fork, nerves, etc.
Good point and thread.
I ride an 05 Litespeed Blade and had serious speed wobble problems in 2 IM’s and 3 or 4 HIM’s.
So much so that I still get overly cautious even exceeding 50km/hr , 30mph for those of you living primatively
I was riding Hed H3C’s in all of the wobbles. Some were so violent they shook my Gu-Gel bottle from it’s casing on the top tube !
The geometry of the set uphas been checked and I have been Retul fitted in the race set-up.
I eventually found that the problem was an out-of-true rear H3C.
The wheels are only EVER used to race and a 10-20km pre-race ride to check the ride and feel.
Since then , no wobbles but I will confess that when I raced IM Canada 09 , I had minimal confidence descending and was passed by everyone’s grandmother
I would double check your wheels for trueness and your set up by knowledgeable mechanics. I am by no means an expert in this field but providing my own experience.
I’ll second the PP. Sometimes it is just a matter of applying pressure to stop the wobble. If I take hands of my P2, the front end starts to wobble SCARY! Simply putting hands back on the bars stops it and it Is very solid thereafter. Perhaps somethng as simple as putting you legs on the top tube might do the trick. If the bike feels confortable otherwise, try small changes (like the leg on the top tube) and find a good decent.
Good luck, fix it fast! At IMSG, good descent skills (and confidence) made the difference between a 17mph and a 18mph bke split.
if you search the net for that reference or the seemingly more appropriate “death wobble”, you will see lots of remarks. you will also see tons of suggestions about how to tweak the bike. what needs adjusting is the rider and position.
It’s not something that a tri-bike should do. I have had two and neither of them did that. I descend at over 40 MPH and I feel VERY stable. I just can’t go any faster cause my gears start spinning.
If it didn’t do it at first, but now is, I’d also rec loosening the stem, tightening the headset/race/etc. and go from there. Other than the inherent crappy handing issues of being in the aerobars when downhill at 40+ mph, you should have any speed wobble over a road bike.
good way to check is to hold the front brake tight, push the bike forward and back - is there any play?
I had the same problem on my Kestrel km40 7 years ago. I was convinced it was the bike. But I was told later that it was mostly do to me being nervous. I’ve had that issue with other bikes, but never as bad as with the Tri bike.
If it didn’t do it at first, but now is, I’d also rec loosening the stem, tightening the headset/race/etc. and go from there. Other than the inherent crappy handing issues of being in the aerobars when downhill at 40+ mph, you should have any speed wobble over a road bike.
good way to check is to hold the front brake tight, push the bike forward and back - is there any play?
+1. Check the headset first, then the front wheel. If neither of those work you might look at your position and for differences over your road setup on weighting issues, but you should be able to fix it pretty easily. Then just practice some quick descents to get the confidence back.
Had my first wobble at IMSG (2nd lap) and thought my bike was falling apart. First lap I hit 47mph on the downhill but on the second lap I got the wobble at 37mph. Scared the crap out of my and I had to ride the brakes to a complete stop to check my bike. On the following descent, the guy in front of me had the same thing happen so I jumped on the brakes and played it safe. The cross-wind was a bit extreme there.
if you search the net for that reference or the seemingly more appropriate “death wobble”, you will see lots of remarks. you will also see tons of suggestions about how to tweak the bike. what needs adjusting is the rider and position.
x2
Funny how the majority of the answers went straight to problems with the bike. While it could be the headset or wheel out of true, I’d ask one thing. Were you coasting? Pedal out of it. If you have a death-grip and coast it’ll make the wobble worse. Pedal harder and it should go away. Easiest trick for rider position.
Start with better weight distribution as you’re descending - in the vein of DHeineck’s comments. Transfer more of your weight from the high moment positions (i.e. aerobars and saddle) to the center - namely the top tube and BB (via pedals). This will provide better weight balance between the hubs and improve the responsiveness of your front end. Maintaining a light pedal load is a good way of accomplishing this (if your speed and gearing are conducive to it). When you’re coasting back on the saddle, the front end is effectively floating and subject to greater lateral instabilities. You’ll definitely notice the difference if you descend through a crosswind. Natural tendency will be to push more of your weight forward (i.e. over center) to null out the yaw.
I have the EXACT same problem on my Argon E-112. Scared the crap out of me at IMLP last year and rode the brakes the entire way down the descent. Rode the course the year before on a Litespeed Tachyon and didn’t experience anything like that and was the same weight year over year…have had people tell me it should be happening and could be due to bearings or whatnot, but nothing has fixed it (happens on race and training wheels, too)…if you figure it out let me know!
This thread reminds me of last weekend’s long ride. 100 miles, 12,000 feet of climbing with numerous 40+mph descents ANNNDDD…40-50mph wind gusts. Good thing I wasn’t riding a disk.
