happy_cyclist

I recently bought a new 2022 Trek FX 3 fitness hybrid from my local bike shop and I'm having 2 concerns about its 1x drivetrain...

First, the chain ring (or maybe the chain itself while on the chain ring - I'm not sure) is making a little noise when I'm using the 2 or 3 lowest/biggest gears in the rear. It's not real loud but it does get louder the lower/bigger the gear (the lowest/biggest "granny" gear produces the most noise). I brought it in to the bike shop and they said there wasn't anything wrong with it and mentioned the greater angle the chain is at when using those gears. It's not loud enough right now that it terribly bothers me but I'm wondering if it will get worse as time goes on, as well as whether this setup is going to cause problems long term with any parts of the drivetrain.

Second, when I get to the top of a hill and have been in the lower/bigger gears to get there, I'm left having to upshift through all the rear gears to get to a high/small enough gear to get going. If it's an immediate descent, I have to pretty much shift all the way to the highest/smallest gear. But even if it's a plateau, I still have to shift through a number of gears. This obviously takes time and kills any momentum I may have had coming up the hill. I kind of stall out while upshifting, especially on the plateaus where I don't have gravity to start pulling me down a descent. I'm wondering if a 2x drivetrain would get me going quicker at the top of a hill due to being able to immediately upshift to the bigger chain ring. I realize I would probably still be in lower/bigger gears in the rear, so I might have to do some upshifting there. Does a 2x get you going quicker at the top of a hill than a 1x?

I'm somewhat of a beginner when it comes to gears and not very knowledgeable, so it's possible that these concerns may be due to some ignorance. And other than these concerns, I love the bike. I do have 30 days from date of purchase to return it to the bike shop, so I'm trying to figure out what to do. I chose the FX 3 over the FX 2 for a few reasons - one of them being the usage and maintenance simplicity of the 1x drivetrain (the FX 2 is a 2x). The other reasons being the better components and gears and the carbon fork. I would provide direct links to the 2 bikes but I'm new here and the registration email said that you can't include URLs in your first 10 posts (which is understandable).

I would greatly appreciate any thoughts or feedback people may have. Thank you.

Iride01 

Yes you'll probably hear noise when the chain is at other than ideal angles. In the 10, 11 or 12 tooth cogs you might even feel a vibration when you are pedaling with a little bit of muscle while at high speeds. Normal stuff. Bikes aren't intended to be stealth vehicles.

Yep, with 1x you do have to shift through all the gears in order. 2x or more will let you short circuit that somewhat. Though I think as you get more bike fit, you might find yourself shifting more often as conditions change. I'm thinking that maybe you just are a tad worn out at the top and aren't shifting as the grade gradually changes as you crest the hill to keep your best power to the pedals.

Many times while cresting a hill I will be shifting with every turn of the crank. And sometime more. Though you need to keep a good RPM on the pedals for shifting. If you are less than 50 rpm, probably a problem, if you keep 70-80 rpm up the hill, shifting is easy and doesn't sound like you are destroying your cogs or chainring. <grin>

Welcome to BF!

HillRider

One insurmountable problem with wide range 1X drivetrains is the large gap between adjacent gears ratios. Also, as you note there is no shortcut in going from a very low to a usefully higher gear, you have to shift a lot of cogs. I think you will adapt in a few rides.

happy_cyclist

Thank you for that feedback and information. That makes me feel better. I think you're probably right about me not shifting enough as I crest the hill. I'll have to pay close attention to this on my next ride.

I do have a general shifting question though. I was actually under the impression that I should be easing up a little when shifting to reduce the stress on the drivetrain. Is that correct? You're saying that I should be keeping a high RPM when shifting, which sounds different from the way I've been doing it. This seems to affect me the most when I'm going up hills and want to downshift but I'm worried that I'm going to be putting too much force on the drivetrain due to me having to pedal hard to remain going forward uphill.

Rolla

Yes, you should let up a little while the chain is actually moving to a different cog, but as long as you're not putting maximum strain on the chain during shifting, you should be okay. Spinning at a higher RPM usually means a lighter load on the pedals, and that's the important part. Alternately, you can stay in the same gear (or even shift to a harder one) and stand up.

tyrion

1) The drivetrain will probably get a little quieter as it breaks in.
2) 1x drivetrains will always have a little more (than 2x) cross-chain noise/vibration in the extreme gears.
3) You have to plan ahead with your shifting so you don't get stuck at the bottom of the hill in high gear and vice versa. At first you have to think about this, but soon you get used to it and you do it without thinking.

Barry2 

Welcome to bike forums

Does the shifter on your FX3 permit changing two rear cogs at a time by pushing the lever further ?
Sorry, not familiar with your particular setup, some do some don't.

All the best

Barry

BTW... That's a really nice bike, I've tried to convince my wife to test ride one.

happy_cyclist

Ok thanks, that makes sense. I think at this point it would probably be a good idea for me to watch some youtube videos on gear shifting to get some visual instruction of what it should look/feel like.

happy_cyclist

Thank you both. Those are great points. As I'm reading the responses, I'm feeling a little more comfortable with the 1x while also realizing that it isn't going to be perfect (no setup is).

Litespud

Your gearing is sequential - that's just then way the drivetrain is designed. However, you don't have to wait until the very top of a climb to start shifting to higher gears - as the climb starts to level out, shift to the next higher gear, and then the next as the slope level out more - there are plenty of usable gears between "lowest gear for climbing" and "highest gear for descending". There are times when simply shifting between chainrings in a 2x or 3x drivetrain is useful for abrupt changes in slope, but more often then not, simply understanding what you're gears are doing and anticipating the need for a gear change is more useful.

Digger Goreman

I am not the paragon of all wisdom, but this is how I shift uphill on my 1x: As I crest the tall hill, I can feel my cadence (pedal speed) increasing and will start shifting to stronger gears. My bike is an old mtb, retrofitted and with thumb friction (non-indexed) shifter, so I can do several cogs at one time if necessary. I don't know if you can on your modern setup. Nevertheless, when you go to shift, just reduce pressure (or ease up) to make the shift. As others have stated, under pressure is where things clunk and jam a little. So, waiting to crest is usually a good idea. Scanning ahead and "anticipation shifting" is something else I do. When I see a hill coming up, I will shift to keep cadence same to a little higher. It's amazing how fast momentum dies on the uphills

happy_cyclist

I don't know. That's a good question. I guess I can test it during my next ride?

The bike is great so far other than my gear issues/concerns. But those are probably due to my inexperience/ignorance and I would probably still have some issues with a 2x.

tyrion

According to this page https://www.trekbikes.com/us/en_US/b...-disc/p/35021/ the bike comes with a Shimano Deore M4100 shifter and according to this page https://bike.shimano.com/en-EU/produ...L-M4100-R.html that shifter can shift 3 gears at a time.

Iride01 

Just to re-iterate what Rolla said in a slightly different way, when you are pedaling at a higher cadence, you usually have less actual force on the pedals. So you can very often shift with virtually no letup on the pedals. If you are climbing at a slower cadence, then there'll be a lot of force on the pedals, and you'll have to slack off the power you are putting into them briefly as you shift.

Not sure if that's any better than he said it or not. But maybe you get the idea. When I'm pedaling at 90 rpm and above, I almost never slack off on the power to the pedals when I shift, unless it's unconscious conditioning that I do.

phughes

One reason I love the friction shifting setup on my touring bike. One long flip of the shifter and I'm all the way From the smallest to the largest cog.

HillRider

I have Gevenalle shifters on three bikes and use 10-speed Shimano bar-end or downtube levers as the rear shifters. These are indexed but also allow a full sweep of the cassette with one push. Best of both worlds.

Bill Kapaun

If you have a typical "trigger shifter", you can push 2 or 3 gears (kind of depends on hand/finger size & ergonomics) with one thumb stroke & repeat.... Just keep turning the cranks with lighter force. It kind of becomes necessary if you suddenly have the traffic light change while you're cruising in the higher gears and want to avoid being stopped in too high a gear.
(I just drop my triple to the granny ring and push a couple times with the thumb while braking on my 3x9's)

You can "release" the other trigger repeatedly quite quickly and pretty much do the same thing to move to the higher gears/smaller cogs.

Just practice a bit and you'll get the idea.
Find an isolated parking lot/road and just work on it a bit.
It'll become 2nd nature.

phughes

My original bar ends shifters were like that as well, until the indexing portion of the shifter broke. I ended up liking friction so much I replaced them with the Rivendell Silvers which are fully friction. The indexing/friction shifters were very nice though,

hokiefyd 

You may also consider an indexed thumb shifter. Like a friction shifter, it will let you dump (or climb) a bunch of sprockets at once. I don't know how many options (if any) you have compatible with your particular drivetrain, but it's something to consider.

SoSmellyAir

The linked Shimano product page says: "Shifts max. 3 gears at a time (Main lever)"

The main lever (thumb) pulls on the shift cable and moves the chain to a physically larger cog (i.e., down shift to a lower gear ratio) while the trigger (index finger) lets the chain drop to the next physically smaller cog (i.e., up shift to a higher gear ratio).

So being able to down shift 3 gears at a time is only useful for climbing, while the OP wants more rapid up shifts after cresting a hill.

happy_cyclist

Yes, that helps. You both explained it well (as did some others in this thread) and gave me things to think about. Thanks.

I think I understand that it's all about force/power/load. If you're putting a lot of it on the pedals, you probably want to ease up a bit to shift. But if you plan ahead properly for the upcoming terrain and get your cadence right so that you aren't putting strenous effort into every revolution, you're probably ok to shift without easing. Do I have that right?

happy_cyclist

Thanks for pointing that out. I would have gotten confused by it.

And I've actually been afraid to shift gears too rapidly because I didn't want to do something wrong, so learning to do this would/will take a little practice.

Edit: Come to think of it...doing this seems like it could be a little dangerous if you don't know what you're doing. It seems like this would most come in handy if you get caught on a hill in too high of a gear. At that point, you're probably having to use a lot of force on the pedals. If you don't ease up enough when trying to downshift 3 gears at once, is that even worse for your gears than trying to downshift with force 1 gear at a time?

happy_cyclist

I think I have a typical trigger shifter...and based on what tyrion and SoSmellyAir pointed out, I can do 3 at a time with the thumb.

I'll have to practice this, as well as the "release" you're talking about with the other trigger to move to higher gears quickly. That's a good idea about working on it in an empty parking lot. Thanks!

Bill Kapaun

Remember to anticipate your downshifts. If you wait until you HAVE TO, it's too late. Keep your cadence up and let the gears do their thing.

happy_cyclist

If you anticipate your downshifts, is there ever a need to do 2 or 3 gears at a time? Just trying to think of how that would be utilized. I guess if the road/terrain was about to get steep very quickly?