Drivetrain Question - gearing up!

[Mikku]

I’ve always ridden with the standard 44/16 gearing, so naturally chose the same set-up for my Crupi. However, I’m now thinking about trying something a little different, more specifically, going up a size of chainring to 45t. The reason for wanting to try a slightly higher gearing is two-fold. Firstly, I have a fair bit of leg power (I snowboard quite a lot during the winter, and do a lot of walking all year round) but as I’m now finding out, easily run out of steam on track. Yes, I could try to get fitter and improve my stamina, which I’m working on, but am not expecting much to happen soon in that department, and it actually mirrors what I was like when I was younger, when I made the school sprint team but was useless at anything over 100metres!

I therefore feel that a slightly higher gearing would allow me to carry a bit more speed through both the non-pedalling (rhythm) sections, and the pedalling sections, the idea being that I don’t have to pedal so much! Secondly, there are some places on the track where I’m only putting in a few turns of the crank, so if I had a higher gearing, then I think I could get more out of those turns. By that I mean that I could get more return (speed) on my investment (pedalling effort)! Not sure how sound that thinking is, but that’s where I’m coming from.

I don't want to try anything too different, hence the single-tooth increase of chainring idea rather than going down to a 15t freewheel/cog, which would produce an even stronger/higher gearing.

Would therefore be interested to hear your thoughts on any or all of the above nonsense!

[deeman]

I imagine different setups would suit different tracks...much like car racing! 

[Mikku]

I imagine different setups would suit different tracks...much like car racing! 

That's true, hadn't thought of that! Midoriyama is quite long, whereas Kawaguchi is much shorter, so may actually be better-suited to 44/16. Am planning to go back to Kawaguchi this weekend, so after 3 consecutive weekends at Midoriyama, will see how they compare.

[Dark Diggler]

Are you talking about racing or just enjoying the track?  the reason I ask is that 45/16 is not a good gearing for gates, or getting back on the gas out of turns or if you lose speed for what ever reason, so in theory, you would be at a disadvantage in a reasonably competative field of riders who gate well.
I remember some people using 41-15 on a 20" which would be ever so slightly lighter than 44-16 and therefore quicker out the gate, like for like (in gearing inches, 44-16 is 55, 41-15 is 54.67-slighly quicker of the mark) The downside of this would be feeling like you have run out of gearing on a fast straight but the phrase "spin to win" is something you hear alot in racing.
Best thing to do is survey a few riders and then watch them gate/race and deffinatel try a 45, theory is all well and good but if you can push a bigger gear and still be in the mix at the end of the 1st straight, it might work for you.

[Drawn]

45-16 is a bit of an old school gearing back when the tracks were a bit flatter.
Have a bike with such gearing from around the 03-05 era and it was a bit of the done thing back then.

In all honesty, it really is up to personal preference. Many will say spin to win, but if you are out there to have fun then run what you feel comfortable with. Just changing tyre manufacturers can change the roll out in a big way let alone changing the tyre size from a 1.75 to a 1.65 or so on. Not sure if it is allowed (delete if needed) but Shane has a really awesome gear calculator that I highly recommend you play with that will help explain things http://bmxultra.com/gear-calculator/

To put it into perspective, I used to run a 38-16 on the cruiser (its now a 35-15 for chain clearance) and a 40-15 on the OS20. the 40-15 gearing is depending on brands very similar to a 45-16 on a standard 20. My gates and leg speed have always been a bit slow so I am happy to take a penalty and ride what is comfortable.
Interesting to note, We do gate timing at our big events and since dropping to a 35-15 on the cruiser while also running the 40-15 on the OS20 which are quite different in Gearing my times to the bottom of the hill are generally identical. Cruiser does feel easier, but after about the 3rd pedal stroke I don't really notice it much at all.
Taller gearing at times isn't always a bad thing. A mate runs a 43-15 which when calced works out to around a 45.5-16 for most others. But his training and power output warrants such a choice (Lets just say, Alloy Cranks are not able to be run haha)

Also just an interesting thing I have learnt from coaching is that over time you do eventually learn without having to think where your pedals are coming to a jump. When you change gearing you actually have to relearn as such where your pedals are by a certain time so those that do constantly change gears can get caught out with feet in the wrong positioning or miss being able to get an extra pedal rotation in. It becomes an unconscious reflex as such.

Would recommend that you give it a go though and see how you feel. Just don't go too big of a change though.
If you feel comfortable then stick to it and see how you go. Afterall you are out there for some fun.
You may find overall the 44-16 to be more friendly but you wont know unless you try.

[Mikku]

Thanks for the replies guys! My perspective is that of a newbie with only 2 races under his belt and who is in it for a bit of nostalgic fun rather than anything else! That said, I don't want to finish last all of the time!

My problem is that I run out of steam, rather than gearing, so it's the speed I can generate out of my (limited) spinning/pedalling that I'm trying to increase, hence the idea of a slightly higher rather than lower gearing. If I went down a bit, i.e. to 41/15 then I think I'd be knackered even sooner than I am now!!

Hadn't thought about the impact of tyres, so will look into that though am very happy with the Maxxis DTH that I'm currently running on. I'll see how I go at Kawaguchi this weekend, then will have another think about it all. If anything, I'll probably try a slightly higher gearing, as that'll be the easiest and cheapest option.

Thanks again Radsters!

PS I've just re-read this and tbh, I know there are far more useful things I can work on before changing my gearing, the first being my fitness, but we all like to play with our bikes, don't we!

[Mikku]

Having spent the last 2 Sundays practising there, I think my 44/16T gearing is just about right for the Kawaguchi track. It’s small and fast, so I think the ability to quickly get up to speed is more important there than on a longer track, such as Midoriyama. However, I still think a slightly higher gearing might work in my favour at Midoriyama. I've attached a gearing chart below – it doesn’t factor in tyre size but has the same figures mentioned above by DD.

I’m only looking at a slight change of gearing, but also don’t want to have to change both the front and back ends to achieve that. A 45/16 would give me a ratio of 56.3 which is not much higher (than the 55 ratio of 44/16) but would only mean a change of chainring. There are slightly lower ratios that are nearer to 55 (42/15 and 39/14, for example) but I’d need to change two parts for those.

However, as I’m slowly gaining speed on the track, I’m going to keep running 44/16 for the time being and get a few more races under my belt, then maybe pick up a 45t chainring in a few months time. That's the current plan anyway!

[Drawn]

Good idea to stick with the 44-16. There is a good reason why it is the general standard or the go to for almost everyone haha.

Would still recommend against changing gears between tracks though, best to stick to one due to being able to do things without thinking and by changing even minutely it can throw your unconscious thinking off majorly. No to mention the geometry change with the wheel being moved etc.
But on the other hand, nothing wrong with trialling a 45 once you do get it.

Oh and one last thing. Going smaller with the gearing for the same ratios can cause more mechanical stresses and wear on the equipment.

[oldtired]

i'm not sying don't change components if you want,  but,

stick with 44/16 and pedal faster      


     i think as you said earlier your overthinking things, you've got a real good set up , focus on getting used to it and putting it to good use and enjoying the racing, 


at the stage your at i think learning to get out the gate fast and being in the pack at the first berm would be more advantageous to you

[Mikku]

Thanks guys! Appreciate the advice and feedback, as always. This just about hits the nail on the head:-

at the stage your at i think learning to get out the gate fast and being in the pack at the first berm would be more advantageous to you.

[OrgasmDonor]

Are you talking about racing or just enjoying the track?  the reason I ask is that 45/16 is not a good gearing for gates, or getting back on the gas out of turns or if you lose speed for what ever reason, so in theory, you would be at a disadvantage in a reasonably competative field of riders who gate well.
I remember some people using 41-15 on a 20" which would be ever so slightly lighter than 44-16 and therefore quicker out the gate, like for like (in gearing inches, 44-16 is 55, 41-15 is 54.67-slighly quicker of the mark) The downside of this would be feeling like you have run out of gearing on a fast straight but the phrase "spin to win" is something you hear alot in racing.
Best thing to do is survey a few riders and then watch them gate/race and deffinatel try a 45, theory is all well and good but if you can push a bigger gear and still be in the mix at the end of the 1st straight, it might work for you.

My gating was always shite so tried a 45 as thought I might claw something back elsewhere, as above, Diggler is spot on, 44 will allow you to wind out berms quicker and that's where I made up distance with a 44, lost it with a 45.

Deffo try different gearings tho otherwise you will always wonder 

[Mikku]

Thought I'd update this thread with developments!

Last summer I bought a Bombshell/Alienation wheelset which came with a 17T cog. Not my first choice, so I was going to source a 16T replacement but then I found a used 47t Rennen chainring on the Museum and realised that a 47/17 ratio is only slightly higher than the 44/16 I’d been running with. The 44/16 is 55 gear inches and the 47/17 is 55.29 gear inches. Below is the BMXUltra calculator with my tyres included. You can see the 2 gearings are really close.

Since I'd wanted to experiment with gearing, I stayed with the 47/17 and have been racing with it this year. Tbh, the difference on track is negligible, as the gearing is so close, so I don't feel that I've lost anything. In fact the only time I feel any discernible difference is when I'm pedalling up some of the steeper hills around my house! At the moment I'm therefore going to stick with this gearing but at some point I still think I'll try something higher.