Tips for managing tandem handling quirks: Seesaw, front end washout, etc...?
As I ride more, I am playing with different set ups, tire pressures, bar/stem height, stem length, etc...
Anyone have seasoned pointers for what you've done to change your setup to improve handling?
Has anyone had luck using a Hopey Sterring Dampener to help manage low speed see saw?
Anyone using a Cane Creek Adjustable Angle Headset? Did it help?
What's your pilot set up, bar length, stem lenth/rise/fall, bar width?
Dump the training wheels! Do the Muni
Hey Ben...we are not necessarily seasoned, but, we have put some solid technical, off-road miles on over the past 4-5 months since picking up our tandem. We went through a LOT of the same stuff that you're going through now in trying to find the right setup for the bike (suspension, tires, tire pressure) and the riders (seats, stems, bars, grips, etc). For the first dozen or more rides, it seemed like all I did was make adjustment after adjustment.
In the end, for rider setup, I closely mimic'd our single bike setups as much as I could. That necessitated changing the bar, grips, saddles and pedals. Practically, if you don't have single bikes to take measurements from, you may be spending some time "tweaking" the people fit for a while.
On the bike, we spent some quality time demo'ing one of Alex's bikes and knew that the bike was setup mechanically just fine for our needs. We did end up going with a wider profile rim, the Velocity Blunt 35, which really helped to spread the tire casing and all but eliminate any tire pushing. In fact, the only time we have pushed the front end, we were riding with PMK and his lovely stoker down at Santos in FL and went over hard in some sand that resulted in a broken arm for my stoker (PMK is a fast rider and we were working to keep up while still new riders). We have been more than fine with other aspects of the build/equipment (well...I'm not a fan of the White Brothers fork, but that's another story) and everything has been dead reliable.
As for tires, we are running tubeless WTB Wolverines and usually run about 26-27psi in front and 28-29psi in the rear and have had no problems flatting or dinging up rims. Our mtbtandems.com built wheelset is still as straight and true as when we got them. FWIW, we are about a 270lb team.
Not sure what you mean by see-sawing...but, I have seen no use for a Hopey damper at this point. The xtra long wheelbase has been superbly stable at ridiculous speeds coming down off the mtns in North GA. We rode a few weeks ago at Raccoon Mtn in Chattanooga, TN, which has some pretty big rocks for the South East. Even taking some good hits on the rocks, I never felt like the bars were going to be jerked out of my hands, or that the chassis was terribly upset; not at all like blitzing through the woods on a KTM and hitting a rut and knowing you're coming off the bike - been there, done that!
Overall...the same advice I got here I'll give you and that is to just ride, ride, ride. Then ride some more. Make tweaks along the way and before you know it, it'll be second nature. I firmly believe that riding with my Wife/Stoker in the woods and on the trails is the best form of riding I've experienced yet!
As each team is different, and most ride in differing terrain from everyone else, there aren't really going to be one-size specs for you to adopt. It's going to come down to riding, tweeking, and riding, as mhop mentions above.
And also, while everything is intertwined, you're going to want to minimize changes so you can figure out the results and make future changes accordingly. If you have a bike you aren't happy with and make five big changes and still end up unhappy, you haven't learned anything and have just wasted time (and possibly money).
Perhaps a better way to go about this would be to provide your team background, bike spec, trail conditions, and what you don't like about the way your tandem rides. From there the various tandem riders here can provide more directed suggestions.
MHopton, honestly, you and your stoker are not slow either. Your wash out does happen, and sadly it did resulting in the injury. Your stoker though is a trooper, demanding to finish the ride.
As for the nurse ben questions. Changing the setup...honestly, you can try various methods to try and achieve your request. However, before I would even consider the changes to the machine, I would ensure you are not creating a solution for a problem that does not exist. Tandems can get floppy in the steering. This all has to do with how the weight is placed, and front end geometry. The Fandango is not known as a poor handling machine bone stock.
My guess for some of your low speed flop of the front wheel would be a stoker wanting a better view. It is very difficult for the stoker to really feel their input until it quickly goes wrong.
Ways to minimize this would be for you to ride less and hit the gym more to build Popeye style upper body physique. You could find a smaller lighter stoker that has less effect on cornering and when looking around. The obvious best answer is to ask your stoker to do her best to just follow your shoulders in most situations.
Regarding the machines setup, we had a Fandango 29r that was I guess first generation. The bike handled very well. 29 bikes in general tend to run front frame geometry that is more vertical and less prone to flop or see saw as you call it. If the stoker is not an issue, you should ensure the fork is of a length that falls within a length of what Alex deems proper fr these machines. A long fork, or excess preload can contribute to ill handling.
Other factors are the type of dirt, soft terrain can induce flop, and cause the tire to hunt back and forth.
As MHopton mentioned, they fell at Santos. We have ridden with other off-road tandem friends there also. Many are accustomed to riding hardpack terrain. Sand, soft terrain and ruts are different. Sand requires a lot of momentum to be maintained through the turns. MHopton thought we were fast, nope, just regular riders with experience (many, many miles) of riding sand. That day, we had settled into a fun pace. Our other friends that have visited, also had concerns because sand always feels insecure when riding. Our Fandango saw a lot of sand use also, and honestly, it was incredibly stable. However, on days when the stoker would look at wildlife, I could tell right away from the feel in the handlebar effort.
MHopton mentioned mimicking single bike setup. Sounds like it works for them. I doubt our tandem would match our singles. Likely close but not exact. Our Ventana if measured would probably fall some where between my single MTB and my KTM 250 woods race bike. The obvious difference between single MTB and tandem is bar width. My single MTB has bars that are cut down to 21 1/2", while the tandem is 25 3/4". I would speculate my seat position on the tandem is close to our road tandem and better optimized for 100 rpm over longer durations. The single bike, has a seat position that allows me to spin or mash, but really is optimized to blast through stupid technical terrain without dropping the front wheel in a hole.
I know, long reply...take a ride with the stoker up and down the street, while going straight, have her lean her head, look around, lean to one side, pull hard on one grip and not the other. As captain, learn to recognize these inputs, best to adapt if possible and when in tight trees ask her to be rock solid. This exercise should also let her feel and understand her input besides pedaling is a very big part of the learning curve. AND COMMUNICATE by whatever means to work together. It does make a huge difference, especially when riding fast.
Reps! We don't need no stickin' reps!
We are a bigger team, I'm 6'/200# and my wife is 5'10"/145#, we are riding a base model Fandango 29, WB Twin Crown Loop Fork, Ardent 2.4 fr/rr.
I'm an ex bike mechanic, racer, and distance tourer, so I have a fair amount of set up experience on single bikes, but tandems are a little different
I have not ridden bikes much in the past five years because I am a unicyclist, but because my wife struggles to keep pace with me on her bike, the tandem is our "together machine"
Karen is a suprisingly good stoker, a natural really, she doesn't try to see what's coming, she is very good (getting better) at anticipaing my needs, and of course I am getting better at communicating
For the first ride I more or less took the Fandang out without making significant changes other tha setting the seat height, adjusting the Thudbuster, and setting seat fore/aft position.
I have been making small changes each ride:
Dropped tire pressure to 25psi, ride felt sloppy, likely tire fold, bumped pressure to 30psi and the ride improved. I'm considering changing to an Ardent 2.25 in the rear due to poor mud clearance, possibly a LUST to add a little sidewall support and prevent tire flop at lower pressures.
From the outset I felt very "tall" in the stock set up, stock the Fandange comes with a 120mm pos 9deg stem with all spacers (~35mm) under the stem (max height). After the first ride I flipped the stem to neg 9 deg, which made me more comfortable and improved handling.
I dropped the stem ~10mm, which still sets me "tall" in the saddle, but it's starting to feel more normal. I still feel very stretched out.
I swapped out stems, now using a 100mm neg 7deg, this feels a lot better, not any more twitchy, reach feels more natural. I could probably go shorter, but I'm going to hold off for now and see how a lower stem position feels.
I played with fork air pressure, started stock at 100psi, backed down to 50psi and found it was too spongy; I was concerned over bottoming out the fork. Though sag was good at 50psi, I bumped it 70psi, overall ride improved over the starting pressure. Running dampening one notch from "locked", rebound is set in the middle of the range. I don't feel like the fork is a problem, it feels very stable, if anything I tend to prefer a firmer ride because it handles better; I rode rigid SS 29er for years.
Most recent "untested change"
I removed the 20mm spacer between the headset and the upper crown, then dropped the upper crown to allow for more adjustment, dropping the stem another 10mm drop, so now my grips are now just slightly lower than my seat (~5mm).
*Though Alex suggested that my tandem set up might not reflect my single bike set up, I have started to approach my single bike set up.
1) Cut bars 1/2" shorter on each side at Stoker's request, then after another ride she asked to further reduce the width. She has very narrow shoulders, using ergo grips, she found her hands drifting inward. The stoker bars are ~1" narrower than her FS bike.
I may drop the stem further, though I feel like I'm getting toward diminishing returns when comfort starts to be an issue. With the bars at just below seat level I feel like I have a good compromise between comfort and control.
In terms of the twitchiness, this is only a problem at low speeds when I'm trying to negotiate tight terrain, trees, rocks, off camber climbs, tight switchbacks. There is a tendency to over correct in difficult terrain, esp at low speeds, on a single bike this is easy to compensate for, but on a tandem any overcorrection is amplified by stoker feedback, ie that long wheelbase feeds back into the front end.
This is why I was considering a steering dampener, to slow feedback.
A wider bar is also a consideration, though too wide and I'm gonna struggle to get between the trees...
Her cockpit length is significantly shorter than her FS, by a couple inches or so, the Thudbuster adds a 1/2" rearward movement when compressed, but I wonder if the handling is quirky because she is too far forward. I may slide her seat back ~1/2" and see how she feels and how the tandem rides.
Her bar position is also quite low relative to her seat. We have the stem as high as it will go on the seat post and extended far out as it can go without overcrowding her; bars set just rearward of my set . She is riding a ~1" riser bar, I'm contemplating a larger rise bar ("2-3") combined with shortening the stem, to see if a this would allow her to stretch out and better control her body's tendency to "fall forward".
I know that part of this is due to lack of experience, possibly working on trim and getting the stoker to put her weight back, but there are times when I get the dreaded see saw effect and if I can't get things to settle down then my only option is to stop and press reset.
Dump the training wheels! Do the Muni
Ben, sounds like your setup is close to our Fandango setup. Have a look at the first few posts when I started this topic, there should be some photos of our bike.
The heavy handlebar feel is typical when riding slower in technical stuff.
Reps! We don't need no stickin' reps!
I love the detail in which you all can describe the way that the bike feels. It's so second nature to me that I don't think about it. I think we have our bikes dialed in. We try to mimic the set up of our single bikes.
Stoker feeback on the bike can be a big deal. Having her lean to spit, or even a sneeze can really affect the bike - especially if there is no warning.
I will say that on all of our tandems, my stoker rides more "stretched out" than any of the other stokers that we ride with. We have to cut the male side of the adjustable stem so that it can be shorter (longer stoker cockpit). This could be beneficial to the bike handling, but it would be speculation.
Tire pressure for us is just shy of 40 psi tubeless. Ardent 2.4 up front and either Panaracer Rampage 2.35 rear. We run either a Maverick fork or Fox 34. We are about 270 lbs plus gear.
One last point, I think PMK alluded to this, momentum is your friend. The most troubles (falls) that we have encountered are at low speeds. These bikes are not as nimble as your single and as a result, slow speed maneuverability is more challenging.
Just getting out and riding is your best bet. You will start to answer most of these questions as you get more time in varying terrain. Good luck!!!
Tire choice and pressures are pretty individual, but even 30psi is at the low end of reported pressures the last time we had a tire pressure thread here. Lower pressures at the front definitely tend to bring a wallow along for the ride. I run the front tire (WTB Prowler 2.5) at 40psi.
Originally Posted by Nurse Ben
Upping the pressure can help with front washout. I don't know of anyone who regularly posts here that runs a Hopey. There was once a decent discussion of the Hopey at the Double Forte yahoo group. You could try a search for it there.
Gotcha. Most of that will come good simply with practice riding the tandem.
Originally Posted by Nurse Ben
It's definitely a different beast compared even to a single bike. Ride, ride, ride, and your piloting skill will rise to the occasion. Your frame is going to be nice and stiff, so you aren't going to be fighting frame flex on top of everything else. Which isn't to say surprise stoker input won't be an issue.
If you're getting unknown/unexpected stoker input during slow/tech moments, you're fighting a losing battle trying to make changes to the bike to fix it. Again, everyone rides different. I don't want my stoker to provide turning input, and she'll call out when she needs to adjust or get water, so I know and can deal with it. If your stoker isn't totally comfortable in the back yet and is adding body English (even if she doesn't know it), I can see how if you get into some tight tech or start to juggle the front the stoker getting "up" to see what's going on and affecting things more in a sort of unwanted feedback loop.
You may start to have your stokers hands encroach on the captains butt. On our road tandem (Burley, much smaller stoker cockpit) my stoker's bar position puts her hands right under my butt, and it doesn't work well if she wants to stretch her hands.
Originally Posted by Nurse Ben
Okay, made some more changes, handling is gradually improving:
Changed bars to Marys, more hand position for her, more leg clearance for me.
Slid her seat back 10mm, so she is slightly behind the pedal spindle now, but has a little more cockpit space.
She says she's more comfortable, no more or less jerky in her peddaling, still able to get back on the seat for descents.
She's pretty bouncy on her thudbusterm esp in new trails at speed, so I may go from blue/blue to blue/grey on the dampeners.
Changed to wider bars, from a 680 to 740mm, 30mm rise.
Changed to shorter stem, from 100mm 75mm, -7deg.
Dropped stem height 10mm.
This has really increased my low speed control, I can keep the tandem from "wagging", no increase in "tree" hits, and I can muscle the front end easier. I am also more "aligned" with my front axle.
Downhill handling is still a little edgy at times, I may bring the bars up a little as I have enough pain between my shoulders to suggest I am a little low; grips are even with the top of the saddle now.
I also bumped up the tire pressure from ~24psi to ~28psi, this gives a nice combo of grip and roll, less sidewall flex, still cushions the stoker enough that she doesn't complain. I can't imagine going beyond 30spi, that would make for a very firm ride.
We took two long and very technical trail rides on Sat and Sun, Haw Ridge and Meads Quarry, local Knoxville areas. We are still learning to communicate, working on getting the stoker communicate when she needs to "shift" herself so we don't "surge" at a bad time. On my part I am doing more talk, trying to develop a language for when to stand and when to sit.
The ride we did yesterday at the Marble Quarry was "amazing", very technical rock gardens, steep descents, tight and twisty with tons of rough edged rock, quick transitions, and tight trees. We rode every trail, up and down the toughest trails, even climbed a boulder strewn trail that I few bikes can get up.
Still playing with the fork, now at 80psi, full to half compression setting depending on terrain, rebound at middle setting.
Ordered a 20t ss chainring, will try that for size, if it won't work or it's too low, then we'll bump for a 12-36 cassette.
Getting some creak in the from cranks, I think it's coming from the EBB, so I'll be pulling it appart and adding some grease; cranks are snug as a bug, creaking noise is bilateral.
Dump the training wheels! Do the Muni
Originally Posted by Okayfine
btw - I do encourage my wife and bestest stoker to aid in steering. She can make a big difference on how well the tires grip and how quick we can turn - and she knows how to make it work. I don't have enough practice with anyone else to encourage them to do that - although I have been known to yell "LEAN!" to a novice stoker.
The wife got a little over-zealous on an early-season ride (we were still getting synchronized) and over-steered us right off the trail. It was funny, and then she knew where the "too far" point was. After that we were railing! When she's on, we can get into and out of a turn pretty quickly, like a single - not all these long, slow, bending sweeps.
It's never easier - you just go faster.
You will naturally have a small amount of see-saw on the front wheel of a tandem when riding very slowly. I believe it is the result of cranks both moving forward , then back, together. Normally you will get used to the feeling and won't even notice it above about 3 mph. On a rare occasion if pedaling into a tight turn you will feel that your turn-in must correspond with the turn-in of the see-saw, this is probably what you are sensing. Soft terrain or soft tires seem to increase this feeling. Less weight on front wheel might help. Is it less noticeable since you shortened stem and widened the bar? In any case it becomes "normal" after a while and you won't have a problem compensating for the feeling after a bit of practice. Glad you are having fun on your new toy. I am jealous. I am recovering from knee surgery and am just starting to get on a stationery bike.
I WILL BE BACK SOON.
Just a couple of tips. #! protect your stoker, she can't see what is coming so try to warn her of bigger drops and rocks. #2 learn to communicate through your pedals. sometimes you need to briefly coast or soft pedal through a section to prevent hitting pedals on rocks. My wife is so well tuned to my pedaling that I seldom have to tell her to stop pedaling, she is already sensing the change in my pedal stroke. I am so used to her doing this that when riding with anyone else we keep hitting pedals on rocks because I don't tell them to stop pedaling in time. #3 your stoker is the boss . Sometimes it gets scary back there. Other times they feel that you are in control. Don't force your stoker to ride what they don't feel comfortable on. It will pay rewards in the future. My wife has had us take the tandem on trails that I would never suggest. If she is feeling good she doesn't mind pushing the limits of where we ride, but other days she wants it easy and just a cruise. It is always her choice because I have the handlebar.
MTB Tandem Nut
It's interesting to read your comments on setup. I have put a few Hopey dampers on tandems before, and IIRC they were all for folks who ride in a lot of sand. Not sure if that's coincidence or not, but something to think about.
I notice a tendency to ride slower in technical stuff on the tandem than I do on a single, and I have to resist that tendency. Partly because, as PMK said, momentum is your best friend on a tandem, and partly because the front end "wags" like you describe if we ride too slow. I do know that the balance corrections on a tandem have to be more emphasized than a single since there is more mass trajectory to correct. The small movements the tandem causes from low-speed instability may be magnified, and that's what you're feeling. IOW, the same movements take place on singles, but aren't nearly as noticeable, and much easier to correct, often subconsciously.
I suspect also that your Uni riding brings you some insights on movement-influenced handling nuances that a lot of us might not really think about. It's certainly good reading and info for teams setting up a tandem, regardless of brand. Please keep up the posts!
By Douger-1 in forum GPS, HRM and Bike Computer
Last Post: 08-21-2013, 02:07 PM
By She&I in forum Tandem Mountain Bikes
Last Post: 09-12-2011, 02:25 PM
By madsedan in forum Wheels and Tires
Last Post: 07-21-2011, 01:24 PM
By tosa in forum Wheels and Tires
Last Post: 06-19-2011, 09:48 PM