Another low trail handling thread

[Nathan Briles]

So I finally finished my low trail bike and I'm not experiencing "shimmy" per-say, but am experiencing some low speed wobble.

At speed or down hill it's pretty solid and I haven't been too worried about it, but at slower speeds (or any speed, for that matter) I can't ride without my hands on the bars. When acclerating it feels like the bike wobbles back and forth a moderate amount with my pedaling stroke.

Using a miche needle bearing headset. Thinking my headset might be too tight? I'm not sure what to try next. Soma GR with 38mm tires. Issues happens whether the front end is loaded or not

[Scott Arenz]

Hey Nathan, for what it's worth I have the same issue but haven't solved it yet. A Soma GR that handles great with or without a front load, but I can't ride hands free for more than a second or two without experiencing wobble and losing balance. (A real drag on long rides!) Bike has Switchback Hill tires and a very tight cartridge bearing headset. No shimmy or wobble in any other situations. One of my next projects is to try a roller bearing headset to try to resolve it.

On your bike, perhaps try some damping grease on the bearings? It has higher viscosity than regular grease, and is available in small quantities for hobby applications.

Scott

Atlanta, GA

[Eamon Nordquist]

I personally have never found low trail bikes to be easy to ride no handed, whereas I find high bikes easy to ride no handed (at least above a certain speed). The one difference for me is if I have a handlebar mounted bag, I find I can ride that no handed easier with low trail than high trail (probably because the bag exacerbates wheel flop too much) I don't ride no handed much, so it's never bothered me either way.

Eamon

[Kevin M]

I had the same feeling on my OAC Rambler, I called it micro-shimmy, and after a year of ownership I decided low trail wasn’t for me. It could have been related to the high-end Cane Creek 110 headset, but I like the mindless handling I get with standard-trail bikes.

[John Guild]

Crust Lightning Bolt owner checking in here:

No shimmy issues for me, with or without a load. The bike rides well with my hands off the bars, ESPECIALLY now that the rear wheel has been redished. I'm using a White Industries headset, fwiw.

[Nathan Briles]

Yeah I've never had a problem riding with no hands. I've been doing it since I was a kid and never thought much of it. Love carrying things in the front, and a rando bag is something I've really wanted for a long time but this wobble is really weird.

I do have my cable hanger sandwiched in the Miche headset which is aesthetically suboptimal. Might be throwing something off? This seems pretty mysterious...

[Shane Schaetz]

welcome to low trail. i think you probably have it set up nearly perfect, and i doubt you will get it any better. 

some of us have gone back to mid trail :). unfortunately, the best aesthetics are in the low trail world (imo).

[Nathan Briles]

Isn't part of the benefits of low trail supposed to be the ease of handling with a front load? I thought I was "supposed to" be able to reach in my bag during a long ride and eat a sandwich or put on my coat without wobbling all over the goddamn place lol

It's such a weird feeling, it almost feels like the opposite of shimmy. When I take my hands of the bars, they stay in the exact location I left them in and I am unable to control the bike at all. I think the wobbling might be due to over-steeeing to compensate? The weirdest part is my headset is super loose, like finger tight basically

[Steve Palincsar]

You think maybe your headset is too tight?

On 08/21/2018 09:44 PM, Nathan Briles wrote:
> Isn't part of the benefits of low trail supposed to be the ease of handling with a front load? I thought I was "supposed to" be able to reach in my bag during a long ride and eat a sandwich or put on my coat without wobbling all over the goddamn place lol
>
> It's such a weird feeling, it almost feels like the opposite of shimmy. When I take my hands of the bars, they stay in the exact location I left them in and I am unable to control the bike at all. I think the wobbling might be due to over-steeeing to compensate? The weirdest part is my headset is super loose, like finger tight basically
>

--
Steve Palincsar
Alexandria, Virginia
USA

[Daniel Jackson]

Crank that headset down. As in - overtighten. That’ll help if not eliminate the wobble entirely.

[Nathan Briles]

I actually just went and loosened it to the point of "way too fucking lose" and I was kind of able to control it with my hands off the bars, but it'll almost definitely shimmy at high speeds now, which is worse.

Maybe I'll try re-greasing and wrenching it down next.
Another noteworthy aspect is that I don't have a decaleur. Could that be a source of this issue?

[Shane Schaetz]

perhaps if the weight is shifting, but you should be doing all these tests without anything in your bag, or even without your bag. eliminate as many variables as possible. 

[Pondero]

Very interesting. I don't have that issue on my OAC Rambler, with a Cane Creek 110 headset, at all. I often carry a light/moderate load on my front rack and cruise no-handed easily. I hate to hear that folks can't enjoy the same low trail benefits I have, and wish for a simple solution.

Chris Johnson
Sanger, Texas

[Nathan Briles]

Took the front load off and rode to the store. If I take my hands off the bars, the front end doesn't move at all. I can take my hands off in a turn and my wheel just sits pointed in that direction. If I'm going straight, I can't get the bars to move at all without some really dramatic leaning.

Most people seem to have the opposite problem, but somebody suggested a larger tire diameter to decrease the effective trail. I'm running 38mm gravel kings right now. I don't think 42mm will help any. I almost want try a regular headset

[Alistair Spence]

It sounds to me like a headset issue. I experienced something very similar with a Miche needle bearing headset myself. I ended up substituting the top half of the headset with a regular ball bearing set up that I had lying around and that helped a lot.

My best behaving low trail bike runs a threadless 1" Cane Creek with cartridge bearings. I have two other bikes of almost identical front end geometry but they are running different headsets. The differences are subtle but I believe that the headsets play an important role in the different handling characteristics of what are otherwise very similar bikes.

Alistair Spence,

Paradise, CA.

On Tue, Aug 21, 2018 at 7:49 PM, Nathan Briles <nbril...@gmail.com> wrote:

Took the front load off and rode to the store. If I take my hands off the bars, the front end doesn't move at all. I can take my hands off in a turn and my wheel just sits pointed in that direction. If I'm going straight, I can't get the bars to move at all without some really dramatic leaning.

Most people seem to have the opposite problem, but somebody suggested a larger tire diameter to decrease the effective trail. I'm running 38mm gravel kings right now. I don't think 42mm will help any. I almost want try a regular headset

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Alistair Spence,

Seattle, WA.

[Nathan Briles]

I just spent the last half hour or so fiddling around with different levels of tightness on this headset, and when its quite loose it alleviates the problem a tiny bit, but its still on the border between acceptable and unacceptable. 

I have a Tifosi headset around here somewhere and I guess I can try swapping the top half of the headset out. That'd save me the trouble of buying the IRD roller drive to try out.

I think its kind of curious that your most well behaved low trail has a cartridge headset... 

On Tuesday, August 21, 2018 at 8:35:48 PM UTC-7, Alistair Spence wrote:

It sounds to me like a headset issue. I experienced something very similar with a Miche needle bearing headset myself. I ended up substituting the top half of the headset with a regular ball bearing set up that I had lying around and that helped a lot.

My best behaving low trail bike runs a threadless 1" Cane Creek with cartridge bearings. I have two other bikes of almost identical front end geometry but they are running different headsets. The differences are subtle but I believe that the headsets play an important role in the different handling characteristics of what are otherwise very similar bikes.

Alistair Spence,

Paradise, CA.

On Tue, Aug 21, 2018 at 7:49 PM, Nathan Briles <nbril...@gmail.com> wrote:

Took the front load off and rode to the store. If I take my hands off the bars, the front end doesn't move at all. I can take my hands off in a turn and my wheel just sits pointed in that direction. If I'm going straight, I can't get the bars to move at all without some really dramatic leaning.

Most people seem to have the opposite problem, but somebody suggested a larger tire diameter to decrease the effective trail. I'm running 38mm gravel kings right now. I don't think 42mm will help any. I almost want try a regular headset

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[Alistair Spence]

On Tue, Aug 21, 2018 at 8:56 PM, Nathan Briles <nbril...@gmail.com> wrote:

I just spent the last half hour or so fiddling around with different levels of tightness on this headset, and when its quite loose it alleviates the problem a tiny bit, but its still on the border between acceptable and unacceptable. 

I have a Tifosi headset around here somewhere and I guess I can try swapping the top half of the headset out. That'd save me the trouble of buying the IRD roller drive to try out.

I think its kind of curious that your most well behaved low trail has a cartridge headset... 

I don't think it's an adjustment issue, it's something to do with the way the headset is designed and or fabricated. Even with very little tension on the locknut it felt to me like there was binding going on on the one that I had.

Regarding the cartridge headset, I don't think it's that curious really. The way that the ball bearings have to move through grease that is sealed within the cartridge provides I think a natural damping because of the viscosity of the grease. This allows things to turn freely, but not too freely, mimicking (through a different mechanism) the effect that most people are looking for when they use a needle roller headset.

Alistair. 

[Nathan Briles]

Yeah, that seems like exactly what I'm experiencing...

I guess that expectation makes sense about the cartridge bearings, but I'm not sure why nobody ever really recommends them for low trail bikes. They're much more readily available, and less expensive.

[Mark Bulgier]

Alistair Spence wrote:

> It sounds to me like a headset issue. 

I agree.  My "racy" road tandem was difficult to ride no-hands until I swapped out the (high-friction) Stronglight roller bearing headset for a (low friction) Chris King.  The Stronglight had some "stiction", a threshold you had to overcome to get the fork to steer at all, and then after you got it moving it was still higher friction.  So you'd always be overcorrecting, your reaction coming a bit late and a bit too much...  The situation improved with more practice, but it was never great with that Stronglight HS.

That tandem is fairly low trail, I forget the number, but I always made tandems with less trail than the singles I made.  I was thinking the poor no-hands experience was due to the low trail, but after the King HS went in, it was good at no-hands.

I know, some people need a high-friction HS to reduce shimmy.  But if you don't need the friction damping, then I think it's clear that HS friction is a bad thing for no-hands steering.  So if you can afford to experiment, I'd always start with low-friction and only change to a higher-friction HS if it proves necessary due to shimmy.

Mark Bulgier

Seattle

[Eric Nichols]

Also consider trying a larger tire. A wider (and thus taller) tire will increase the trail. Depending on the season and conditions, I run 40, 42, or 48 mm tires on my Soma GR and the difference in trail is noticeable. A 38 mm tire is at the low end of the range for that bike, and will accentuate handling issues (I.e., shimmy) related to low trail.

For what it’s worth, I recently posted my experiences with damping grease on the iBOB forum, and found it to be ineffective. Switching from roller bearing to ball bearing made shimmy occur. Over-tightening the headset cured it but shortens bearing life. Switching back to roller bearings made it go away. Grease made no difference. YMMV.

Eric

[Steven Frederick]

There was a batch of the inexpensive Miche needle bearing headsets a few years ago that were a little off spec-I had one on my Stag.  It wouldn't set up properly, either it was way too loose or too tight/binding/notchy.  It seemed as though the upper cups were bottoming out.  One guy was able to sort it out by adding some sort of washer or bearing cover or something I don't recall exactly what. I just replaced the Miche with a regular headset and it was fine...

Steve

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[Paul Sherman]

Also worth noting with regard to tire size is that the Gravel Kings are an undersized 38 IME. Switching to a full-sized 42 (Hetre) makes a pretty huge difference.

Paul

[satanas]

Tyres definitely make a difference. Switching from 42mm Hetres to 38mm Écureuils makes the bike noticeably less stable, so I imagine heavier 47+ mm tyres would do the opposite. I had major shimmy problems on my 55cm GR v1 with a Stronglight needle bearing headset, so can't imagine how bad it would be with something easier turning.

More trail (via a new fork) fixed most of the handling issues. YMMV.

Later,
Stephen

[Matthew J]

> My "racy" road tandem was difficult to ride no-hands 

I've never been able to understand the fixation on no-hands riding.  Been riding a bike for more years than many people have been alive.  There have been very few times I've removed both hands from the handlebar.  At least on my bikes the handlebars are so well located keeping my hands on them seems quite natural.

[Bill M.]

I have owned four low-trail bikes.  I have never had one shimmy at speed, but I never found them particularly easy to ride no-handed, especially at low speed, loaded or not.  I have no such issues with mid-fifties or higher trail.  For me, low trail is preferable only when carrying a rando-style front bag.

Bill

Stockton, Ca

[Alex Wetmore]

You can test to see if shifting weight is an issue by just strapping or taping a completely full 1 liter water bottle to the rack and doing a test ride.  That will give you just over 2lbs of fake handlebar bag weight, which is usually enough to calm down a too-twitchy low trail bike.

alex

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From: 65...@googlegroups.com <65...@googlegroups.com> on behalf of Nathan Briles <nbril...@gmail.com>
Sent: Tuesday, August 21, 2018 7:29:49 PM
To: 650b
Subject: [650B] Re: Another low trail handling thread

 

I actually just went and loosened it to the point of "way too fucking lose" and I was kind of able to control it with my hands off the bars, but it'll almost definitely shimmy at high speeds now, which is worse.

Maybe I'll try re-greasing and wrenching it down next.
Another noteworthy aspect is that I don't have a decaleur. Could that be a source of this issue?

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[Alex Wetmore]

I have 5 low trail bikes and only one has a needle bearing headset (3 have cartridge bearing headsets, 1 uses an old Ritchey loose ball headset).  I don't think a needle bearing headset is useful unless you are having light speed wobble problems (the kind where resting your knee against the top tube makes them go away).  I mostly use Shimano Pro cartridge bearing headsets because I bought a lot of them on closeout a decade ago.  They are very close copies of a Chris King.

I agree that low speed handling issues sound like there is something wrong with the headset.

---

From: 65...@googlegroups.com <65...@googlegroups.com> on behalf of Nathan Briles <nbril...@gmail.com>

Sent: Tuesday, August 21, 2018 9:26:44 PM
To: 650b
Subject: Re: [650B] Another low trail handling thread

 

Yeah, that seems like exactly what I'm experiencing...

I guess that expectation makes sense about the cartridge bearings, but I'm not sure why nobody ever really recommends them for low trail bikes. They're much more readily available, and less expensive.

[Scott Stulken]

My take is that apart from doing things like putting on or removing jackets mid-ride, we often bring up no-hands riding here for its diagnostic value:  a bike that you can easily ride no-hands is (probably) correctly aligned and free of headset issues.  And that means it should need less attention/correction when riding normally.

Since a low-trail bike is freer to break into oscillation (all else being equal), it's something that gets noticed by those of us who've done the experiment.

As someone who waited until adulthood to try riding no-hands, I'm not attached to it, either, but I try it on occasion to see if I can get better at it.  One thing I've noticed is that my low-trail bike is very sensitive to pedal strokes when riding no-hands.  Choppy pedaling seems to set off a shimmy more easily than smooth pedaling or coasting, and just being apprehensive about the whole thing has an effect, too!  Riding no-hands (including on the low-trail bike) seems to go smoother when I'm on my way home from a club ride with a couple beers in me.  Not that I am advocating anything... just a data point.

- Scott

On Wednesday, August 22, 2018 at 8:20:22 AM UTC-5, Matthew J wrote:

[Nathan Briles]

This thread has been super helpful, guys. I've got a cartridge headset on order and I'm going to experiment a bit more in the meantime (top half ball bearing/ full ball bearing headsets) to see if I can work it out.

Also, I know I need to get some nicer tires. I've been waiting to upgrade my rims because the Soma Weymouth's aren't tubeless compatible. Might get brevets in the future, but one thing at a time

[Sukho Goff]

I think I may have had one of those Miche needle bearing headsets. Had exactly the situation you described; too loose or too tight. After about a year of riding with it too tight (and really hating how the bike handled), I put in a headset with regular cartridge bearings and never looked back. BTW I didn't have any shimmy issues on this bike (with a Lyon fork with 65mm rake), but used the Miche as a preemptive measure.

Like Nathan, on this bike, (39 trail) I also cannot ride no hands at low speed without the bike veering all over. Kind of defeats the purpose of being able to grab food and change layers safely while still pedaling. My mid trail BMC Road+ tracks dead steady with no hands at whatever speed. Overall I'm starting to feel that low trail bikes are kind of a pain in the ass and isn't for every BODY. Hmm.

Sukho in PDX

On Wednesday, August 22, 2018 at 5:19:01 AM UTC-7, Stevef wrote:

There was a batch of the inexpensive Miche needle bearing headsets a few years ago that were a little off spec-I had one on my Stag.  It wouldn't set up properly, either it was way too loose or too tight/binding/notchy.  It seemed as though the upper cups were bottoming out.  One guy was able to sort it out by adding some sort of washer or bearing cover or something I don't recall exactly what. I just replaced the Miche with a regular headset and it was fine...

Steve

On Tue, Aug 21, 2018 at 1:18 PM, Nathan Briles <nbril...@gmail.com> wrote:

So I finally finished my low trail bike and I'm not experiencing "shimmy" per-say, but am experiencing some low speed wobble.

At speed or down hill it's pretty solid and I haven't been too worried about it, but at slower speeds (or any speed, for that matter) I can't ride without my hands on the bars. When acclerating it feels like the bike wobbles back and forth a moderate amount with my pedaling stroke.

Using a miche needle bearing headset. Thinking my headset might be too tight? I'm not sure what to try next. Soma GR with 38mm tires. Issues happens whether the front end is loaded or not

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[Sukho Goff]

What Bill says mirrors my experience/opinion. But then I never found low trail to be as magical with a loaded front bag as I might've thought, especially from reading BQ's writings on it. And I never found front loads on a mid/high trail bike to be that apocalyptic. FOR ME (and my body and riding style).

With such wide and varying experiences from every low trail thread I've read, it makes me think that there are so many more variables (body weight, riding style, weight distribution, handling skills, pedaling tendencies, tubing, etc etc) to consider before you're able to put it cleanly into a box as BQ has. YMMV (truly).

Sukho in PDX

[Igor Belopolsky]

I can ride no-handed on mine but not as easily as my mid/high trail bikes. My low trail is 35mm trail.

I have 42mm Hetres and a Dura Ace headset. A bit tighter is better. Steering is twitchy without a load, better with one, but I am getting used to riding without a front load right now because I have not found a rack that fits well yet with my Paul brakes. I may sell my Paul brakes because the Dia Compe 980 look nice and may even fit the 'aesthetics' better.

I certainly prefer the handling of my Gunnar Crosshairs but this bike is faster. I need to get a more accurate PSI gauge to try out pressures as well...any thoughts there? I am 175lbs and am riding the 42mm Hetres EL.

Thanks,

[Matthew J]

> just a data point.

Good analysis.  Makes sense. 

[Lee Legrand]

It would be interesting to do some deeper investigation into this.  Following the thread, it seems that shimmy and no hand riding is an issue with low trail bicycles.  It would be interesting if those who do have problems and those who do not have problems would give some numbers up on the trail on their bicycles. It won't be definitive but may give some correlation to trail numbers and shimmy.

On Thu, Aug 23, 2018 at 8:51 AM Matthew J <matth...@gmail.com> wrote:

> just a data point.

Good analysis.  Makes sense. 

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[Stephen Poole]

I doubt that it's just raw trail that matters, but also how it's arrived at, pneumatic trail, wheel weight, frame stiffness, weight distribution, loading, etc. Just considering one thing might not reveal the whole story.

Having said that, with a 72° head angle and 74mm offset yielding 31mm trail, shimmy was pretty much omnipresent above 28-30  km/h, always annoying, and occasionally frightening. With 60mm offset and 45mm trail, I had shimmy once, briefly (but it was on a twisty descent at night, in the rain). FWIW, with more normal trail of 55mm and above on a very wide variety of other bikes I've *never* experienced shimmy, so I'll be sticking with that in future until or unless I get to test ride something with less trail that IMO handles acceptably.

Later,

Stephen

[Lee Legrand]

It won't be definitive but may give some correlation to trail numbers and shimmy.

I doubt that it's just raw trail that matters, but also how it's arrived at, pneumatic trail, wheel weight, frame stiffness, weight distribution, loading, etc. Just considering one thing might not reveal the whole story.

I know it won't be just trail but shimmy and no-hands riding on low trail seem to be an issue that some have and some do not.  It may be a correlation if you can compare the numbers of trails with different bikes.  Of course, other factors contribute.

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[Igor Belopolsky]

I read no-handed, no front rack or weight today. It's definitely manageable just not as ideal as my other bikes ;)

[Nathan Briles]

Yeah it seems really difficult to nail down what exact causes shimmy (still not sure what I've experienced can be called shimmy.
Im surprised nobody has done a more controlled experiment where they test several trail numbers with the same bike, rider, tires, ect. Like 35,45,55mm trail with needle bearing, ball bearing and cartridge headsets.

That might give us a better picture of what helps and what doesn't. Then again, I guess it's kind of difficult to quantify shimmy

[David Cummings]

Anecdotally, it seems that people tend to have a harder time with larger frames (I typically ride 60cm frames).  I have been down this rabbit hole on threads before, and I agree that there must be many contributing factors.  Probably includes frame "straightness" too.  My mid trail Trek 710 with 650x38b tires isn't quite straight and it shimmies - a roller bearing HS calmed it down but didn't eliminate it, especially at high speed; a front load makes it horrible.

Most of my bikes are high trail and some shimmy, others are steady as a rock.  They all have standard cone/cup headsets.  I have never checked the alignment of those bikes on a frame jig or even with string. I think it would take quite an effort to put together lots of data before we started to see a trend.  We have some "treatments" but we don't fully understand the nature of the disease so don't have a true "cure" yet.

[Nathan Briles]

My frame is brand new, so I hope it's straight, but to be fair I didn't check. My last frame was a trek 510 conversion with the same wheelset and tires and I could easily ride hands-free on it without any weight up front. Never tried it with a front rack. I think the trail for that bike was somewhere in the 50's. I should have tried a front rack on there, but p-clamps bug me.

[Eamon Nordquist]

I would clarify that it's not so much that I find low trail hard to ride no-handed, just that at least above a certain speed, high trail just seems so easy by comparison. I have to pay way more attention with low trail.

On Tuesday, August 21, 2018 at 1:03:07 PM UTC-7, Eamon Nordquist wrote:

I personally have never found low trail bikes to be easy to ride no handed, whereas I find high bikes easy to ride no handed (at least above a certain speed). The one difference for me is if I have a handlebar mounted bag, I find I can ride that no handed easier with low trail than high trail (probably because the bag exacerbates wheel flop too much) I don't ride no handed much, so it's never bothered me either way.

Eamon

[Ken Freeman]

I've also been dancing with low trail, but never fully feeling the relationship.  My LT bikes are a Terraferma 650b and a Trek 610 modified with a custom low-trail fork designed for equal ride height.  Both have trail around 35 mm.  According to one of Jan's assessments, 35 degrees is close to optimum for a 650bx42b, and 35 is possibly too low for a 700x28c.  

I have a Mark's Rack on the Terra and a little TA rack designed for a Mafac brake on the Trek (mounted on a Mafac front brake).  The Terra has a Stronglight A9 headset and the Trek has a 10 year old Campagnolo Record headset.  I would not hesitate to crank down the A9, but I don't like draggy steering.  I would not crank down the Campagnolo because I think it is correctly set as I have it.  It cost a bunch, so I don't want to risk ruining it just for an experiment. I would make sure your HS's are set without play, even after hard braking.  Too much drag in a headset (bearings too tight) can increase drag but still run smooth.  More than that and the bearing can stick-slip, or show stiction.  This is where a lotmore force is needed to start the headset turning than it takes to keep the bearing turning.  I imagine this could be hard to control.

Before putting on the racks both bikes have very easy steering with little self-centering force at low speeds.  It's totally up to my arms to hold the fork straight, and therefore it can dither around a little.  But I never feel it losing balance, so it doesn't bother me.  Both are much more stable climbing hills than on my high-trail racey bikes.  On both of them I'm really getting to like the cornering and handling while leaned over - Jan was right that you can change lines in the middle of a curve!  On both of them the steering shows decent stability at middle to higher speeds.

What experienced low-trail riders have said over and over is that once you get a reasonably loaded front bag (2# bag weight plus 5# of gear inside?) the dithery handling of a low-trail front end disappears and it begins to feel like a normal bike again.  I haven't experienced that yet - I have a V-O decaleur, but have yet to drill the Berthoud bag for it.  I have definitely experienced the opposite, the large challenge of steering a high-trail bike with a front rack and about 10# of load in the bag.  I think the front rack exists to hold the front bag up, keep the bottom from sliding forward/backward and left/right.  The decaleur exists to keep the front of the bag from squirelling around.  To my mind if you have a load, you should have the top secured.  Straps to the handlebars might be all that you need.

From where you're at, I would first make sure the headset is correctly installed and adjusted (tighter than WTFL and looser than OMFG It's TFT), the front wheel bearing turns as freely as possible and has no lateral play, the front wheel is clamped securely in the fork and is aligned laterally and with the rear wheel.  For it to be true and dished correctly is also nice.  Then add the rack, a front bag, and a bottom clamp and top support, decaleur or straps or whatever.  Load it up with lunch, a water bottle, a lock and some tools, and head out on a ride.  I expect it will be better, but ya know, I always learn new things when I try such experiments.  I can't say this will solve all your problems, but it should be a step forward from what you have.  I'd also start searching Ebay and Amazon for a roller-bearing headset that fits your frame.  For steering damping, there are such devices available for motorcycles and I think V-O has one for bicycles.  But that would be my last resort.

Not all dithering is shimmy, and hence not all of it is dangerous.  Shimmy is dangerous because the amplitude can increase once it starts, and unless you're pretty strong it can get totally out of control and then you will be thrown on the ground. Only with the high-trail Trek with heavy front load did I feel anything dangerous.  Nothing so far on the same Trek with the low-trail fork.

On Tue, Aug 21, 2018 at 10:29 PM Nathan Briles <nbril...@gmail.com> wrote:

I actually just went and loosened it to the point of "way too fucking lose" and I was kind of able to control it with my hands off the bars, but it'll almost definitely shimmy at high speeds now, which is worse.

Maybe I'll try re-greasing and wrenching it down next.
Another noteworthy aspect is that I don't have a decaleur. Could that be a source of this issue?

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Ken Freeman
Ann Arbor, MI USA

[Ken Freeman]

Alex, when I've had headset problems like that, I usually take frame and fork a good local shop and ask them to face the headtube and crown race mount to make sure they are uniform and perpendicular to teh steering axis.  That has not failed to help me make a headset turn uniformly.

[Alex Wetmore]

I'm not sure why you addressed this to me?  I have my own facing tools (a side product of having built frames) and promise you that every frame in my house has a properly faced headtube and bottom bracket.

There are also some headsets that are pickier than others.  I think I got those Shimano PRO headsets so cheaply because they require a very well faced headtube and milled crown race, they have almost no tolerance for slop.

alex

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From: Ken Freeman <kenfre...@gmail.com>
Sent: Thursday, August 23, 2018 3:17:31 PM
To: Alex Wetmore
Cc: nbril...@gmail.com; 650b

[Nathan Briles]

Ok y'all, some vast improvements have been made!

I swapped out the top half of the Miche roller bearing headset for a Tifosi ball bearing headset. All the notchiness is gone and I think this is much more indicative of how things are supposed to feel.
There is some play in the headset, so I need to tighten it up a bit more (I was afraid of the notchiness from before). The steering is just a little twitchy now, but my load atm is only my acorn bag, a lock and a rain jacket. Little more weight and a little tighter headset should have me in business!

To whoever suggested putting a regular ball bearing headset on the top half, I owe you a beer!

[Andrew Squirrel]

"I've never been able to understand the fixation on no-hands riding."

I will second that notion. Even during long randonneuring rides I always manage to do everything that needs to be done with one hand or using both hands while palming the top of the bar & using the handlebar bag as a work surface. Maybe its my stable and comfortable crouched position but sitting up, away from the bars/bag never seems appealing regardless of the bike between my legs.

[Shane Schaetz]

Riding no handed is about as pure as pleasure gets. I've been doing it almost 40 years (I'm 43), and it is a requirement for any bike I ride, except a tandem. I took it for granted before I started getting into low trail business, and now I never will again.

I've ridden over an hour consecutively without touching my hands on the bar, just as a challenge. I ride more no handed than on the drops...

[David Cummings]

I like to be able to sit up straight, stretch my back, deal with gloves, swap glasses/sunglasses, open up a snack, etc. There are many reasons I like to ride no handed.

Sent from Dave's rockin' iPhone

[franklyn]

I used to make this a functional requirements for my bikes, but after doing long brevet-styled rides for now almost 10 years on and off pavements, I found myself having that needs less and less frequently (I think I stop more and get off my bike more nowadays; and I do what Andrew does). That being said, I still test the no-hand abilities of my bikes from time to time just to know what I should expect. I have five low-to-mid trail, 650b bikes, all of which has a front rack and luggage, and the narrowest tire width I ride is 42mm. And all of them have moderately light to very light tubings. They all have different no-hand abilities and behave differently when I take my hands off. The Kogswell (allegedly 30mm trail) has a big porteur rack and carries heavier load frequently. If the weight is loaded evenly across the left and right side, the bike goes straight with no hands. Otherwise the bike tends to veer toward the side that has noticeably more weight in the front. The bike does not shimmy

The Ebisu is a mid-trail (mid to high 40's) bike and has a 1 1/4 downtube (every other bike I have has a 1 1/8 downtube; every bike has 1" top tube) and is by far the most stiff bike I have. It has amazing no-bike ability and with needle bearing Stronglight headset it does not shimmy.

The 650b-converted Specialized Sequoia has a low-trail Kogswell Konversion Fork and uses a cartridge bearing. It does not shimmy and I can take my hands off easily. It's on the stouter side of my bikes

The next two bikes are more flexy compared to the three bikes above (though all 5 'plane' for me), and these two have less "no hand" abilities than the other three. The rSogn and the Fitz Custom both have low-trail front end, and flex more than the other 3 (though the Ebisu is slightly lighter than the rSogn, but has a stouter downtube). These two require more attention and speed to take my hands off. The Fitz requires me to put my knees on the top tube to prevent shimmying. Both use cartridge bearing headsets. 

I gladly trade the lessened no-hand ability of the Fitz for its exceptional ride quality, and with my hands on the handlebar, it handles with aplomb on and off pavement.

Franklyn 

On Thursday, August 23, 2018 at 4:08:28 PM UTC-7, Andrew Squirrel wrote: