What do you all use to time your downhill runs?

This seems like an easy, immediate solution.

https://www.sportcount.com/sc-products/

My son races DH professionally.  He and all his buddies use the Crossbox and love it and find it does the best job.

i got an extra mount and use my edge 830 to log DH runs

I use a combination of a GPS watch and Litpro. It's not maybe the most accurate, even though I haven't tested its accuracy, but I feel it's the least invasive or costly. 

Strava. 

It effectively hurts many egotistical emotions at the same time. LOL. 

Great question! FYI, Garmins (and other GPS devices) are significantly more accurate than the GPS in a phone, so if you're trying to time runs using Strava, it really pays to have a dedicated GPS device. In addition to that, Strava knows and advertises the limitations of their GPS segments, which you can read about here: https://support.strava.com/hc/en-us/articles/216918227-Optimizing-Segment-Creation-How-to-Create-Good-Segments TLDR: any segment that's around a minute or less is likely to produce inaccurate times, switchbacks are bad if they're near a start or end point, other trail segments nearby will confuse the GPS and may produce faulty segments, all of which can affect DH trail segments in mountain bike areas.

For accuracy, there's no substitute for a stopwatch. The Sportcount watch is great because, in addition to being cheap, your time variance will likely be pretty consistent once you find your groove and get familiar starting and stopping the watch. By contrast, GPS can be thrown off by a bunch of variables outside your control.

Siri start/stop stopwatch.

I'm working on my own lap timer iOS app and handlebar mounted bluetooth button called Cyclaps. The bluetooth button mounts on your handlebars and communicates directly to the Cyclaps app to start/stop timing and mark segment times. Just hit the button on your bars next to your thumb. It can be MUCH more accurate than any GPS and you can time anything/anywhere you'd like. The Cyclaps app can be set to record simple times or segment times. All lap times are recorded to a file on your phone that can be filtered and shared. Cyclaps does not use any data connection beyond bluetooth (internet or GPS) to work and so is very fast and can be used in the most remote places where GPS, 5G or wifi are not available.

If you are interested in testing Cyclaps, please let me know. Currently, it is only available for iOS. The Cyclaps app is very far along and works very well. I'm mostly working on better ways to mount the bluetooth button.

If you need a guy from the midwest/plains states trying to ride XC trails and livestock/wildlife trails aggressively and - consequently - crashing pretty often but not that hard...I'm your guy!

If you would award bonus points for being a higher-than-average sweater and much-higher-than-average salt content in that sweat then I'm getting a dripping helmetload of bonus points. Practically on command, I can sweat on it with a sweat salty enough to bleach a black shirt as I REFUSE to brake for one particular nemesis of a flat corner that bounces me off the trail once a week!

You can just use a GoPro and that's what many pros are using because it's the most convenient.
The benefits is that you have much more information than just a time, you can look at sections, compare runs, split time..etc.. For a long time I was using spreadsheet but I finally made a webapp  at https://www.victorise.co to upload all my gopros and compare runs, split times, etc.
( this app also allows to overlay data from suspension data acquisition (from BYB-Tech) or brake information (from Brake Ace)
Do you know most gopro (anything recent but the 12 and the session) have already a decent GPS (and accelerometer) so you can really gets lots of info from it..
I'm still working on this tool so feel free to try it and give me feedback so I can keep improve it.
You can get more precise time from Freelap, Crossbox, Litpro but it's expensive and a pain to deploy..

This little guy does well. Lasts 2 or 3 seasons before it dies or gets lost.

Little velcro on the bar  and back of the strap helps retention.

With the Crossbox you can have set tracks like Strava with splits and can compare with others on the same track.  The Crossbox seems to be very accurate and reproducible. The boys are always analyzing laps between shuttles.

I've been tracking against the clock for a while, with two different setups:

-The original motion instruments kit had a very good handlebar bluetooth button that allowed for logging time stamps. Worked great, until an update made it essentially non-functional, with a need to regularly reconnect the button with each new run. When it worked, it was golden as you had time, notes, and hard data all in one place. 

-I started using a sportcount timer, fixed to the handlebar with a bit of dual sided tape after the motion instruments setup crapped out. It works, but has a few serious flaws. The biggest is there isn't an indicator the system is clearly on or not. There is nothing worse than feeling like you put down an absolute heater of a run and find you either didn't term the timer off at the end, or on at the start. The second is it doesn't store times from past runs. Not a deal breaker, but it's nice to have all of one's runs, and where they occured, nice and organized. 

A  handlebar mounted setup like @brianroelofs is working on sounds pretty good. Even better if the on/off handlebar button has an indicator for when it's running. There is a discontinued product that comes up in a google search (DRC-X timer) that takes a more self contained approach and that seems pretty ideal. 

+1 for gopro. you can set frame rate 100fps to get very accurate times if you really want to (.01). definitely more of a PIA for on-trail analysis.

your app looks rad BTW.

Litpro when I want to time

i used to do timed runs, used my Garmin with the control/switch it's wireless of course. 

-shows your "lap times' in the data fields as you record/ start/stop etc.. pretty cool as long as you have a controlled start/stop setup environment.

 I think it even came with my Garmin edge 520 or 530 I believe. It came with a mount which i put as a thumb switch next to the grip. can see times as you ride, sort through your data fields. and look back on it later in garmin connect / strava. heres the kit i have below

https://www.garmin.com/en-US/p/621230

basically a wireless stopwatch with data on screen. Garmin mounted to top tube with Project 76 mount.

cheers

When accurate and precise timing is needed, it is Freelap that I use. It's not cheap, but works well. It's also easy to get timing data from multiple athletes running the same track.

The timing app is run on an old cell phone that doesn't have a SIM card. It will typically be in a pack or left by the finish line to review the data easily and quickly.  Camo tape to keep the transmitters hidden from curious hands.

I’ve spent quite a bit of time nerding out on different timing solutions for DH and Moto. It’s a much trickier problem than it looks when you want something that’s precise, reliable, fast to access, and affordable.
Before diving in, a few important truths:
- Humans are terrible at estimating time: our perception is easily tricked by vision and vibrations. A rider might feel faster on a stiff bike bouncing in a rock garden, but actually be slower than on a smooth flow trail.
- Longer sections are easier to measure accurately: trying to measure a 1-second difference on a 20-second Strava segment is silly. But on a 5-minute track, even a 3–5 second improvement is measurable with medium-precision systems.
- GPS Drift and Frequency Matter: Most systems don’t interpolate GPS signals properly. If you’re riding 30 km/h (~8.3 m/s) and your GPS logs 1 point per second (1Hz), a bad GPS fix could place you 5–15m off, easily introducing a 1-2 second error, especially if the point lands before or after your real finish line.
Also,  shameless plug: I actually built two solutions I mention below (https://www.chronocult.com and https://www.victorise.co) — and I would love for people to try them and send feedback! 🙌

📱 Mobile App GPS (e.g., Strava App on Phone)
• Precision: ~2–5 seconds
• Cost: Free (if you already have a phone)
• Ease of Use: Very easy
• Potential Cons:
• Poor GPS quality (1Hz or worst when phone is trying to save battery)
• Drift in trees or bad weather
• No real-time feedback
• Comment: Fine for casual rides, not usable for precise timing.

🚴‍♂️ Cycling Computer GPS (Garmin, Wahoo, etc.)
• Precision: ~1–2 seconds
• Cost: $250–$600+
• Ease of Use: Easy once set up
• Potential Cons:
• GPS still only 1Hz standard (some burst modes better)
• Struggles under dense tree cover
• Comment: Better than phones but still debatable for short segments .

🕰 Manual Timer (Sportcount Ring, Stopwatch, etc.)
• Precision: ~0.3–0.5 seconds (human reaction)
• Cost: ~$30–$100
• Ease of Use: Very easy
• Potential Cons:
• Human error
• Comment: Not surgical, but dependable.

🌐 Chronocult.com (Multi-Phone Timing)
• Precision: ~0.3–0.5 seconds (human click)
• Cost: Free
• Ease of Use: Very easy — just a phone at start/finish
• Potential Cons:
• Needs cell phone reception
• Relies on accurate clicking
• Needs a couple of buddies
• Comment: Perfect for grassroots events, group rides, and DIY time trials! I built it for our local NICA team.

🎥 Manual Video Review (e.g., GoPro footage analyzed manually)
• Precision: ~0.03 seconds (frame by frame)
• Cost: ~$300–$500 for camera
• Ease of Use: Tedious (hours of review)
• Potential Cons:
• Painfully slow post-processing
• Comment: Very accurate but impractical for frequent timing.

🎥 GoPro + Victorise (Video Review Software)
• Precision: ~0.03 seconds
• Cost: ~$300 camera + software/tools
• Ease of Use: Moderate (much faster than manual review)
• Potential Cons:
• Some setup effort.
• Comment: (Another one I helped build!) Great middle ground — pro-level accuracy without crazy gear.

📈 LitPro, Crossbox, or Other High-Frequency GPS Devices
• Precision: ~0.2–0.5 seconds
• Cost: ~$400–$800 + subscriptions
• Ease of Use: Moderate (needs device mounting, post-run sync)
• Potential Cons:
• Still  GPS drift, especially under trees
• Comment: Best GPS-based systems today. Great for training data nerds.

🏁 Freelap Timing System
• Precision: ~0.02 seconds
• Cost: $1000+ depending on setup
• Ease of Use: Moderate (setup transmitters + transponders)
• Potential Cons:
• Expensive
• Needs careful positioning
• Comment: Killer tool for training short sections, sprint intervals, DH runs.

🛂 RFID Timing (Tag + Reader systems)
• Precision: ~0.01–0.05 seconds
• Cost: $$$$ (professional-grade)
• Ease of Use: Complex (needs mats, antennas, tags)
• Potential Cons:
• Very expensive
• Overkill for solo rides
• Comment: Absolute best precision — but realistically only for big setups (not DIY).

📡 New Ideas Coming But no Mainstream Product Yet:
• Bluetooth Beacon Timing:
• Small BLE beacons could theoretically trigger timing at the pass.
• Problem: No real commercial timing product out yet for DIY racers.

• RTK GPS (cm-precision GPS):
• This military tech is public now it would make GPS-based timing insanely accurate (centimeters, milliseconds!).
• Problem: Still too expensive and complex — no consumer products available today.

Any options I forgot?

Could you give us a little more info on Chronocult.com? Could I have a friend at the top and a friend at the bottom of a track, both using their phones as stop watches, but it's updating the same racer's timing with start and finish times?

@TEAMROBOT 

Yes, that’s exactly what Chronocult does.
It is a simple web-based timing tool. You can have a friend at the start and another at the finish - each on their phone - timing the same racer. The system syncs in real time: when one starts a racer, the other can stop them, and it all updates live to the same leaderboard.
- No app required
- Works with QR code or link to invite another timer
- Add/remove racers on the fly
- Works with or without cell service (it should reconcile the data when the phones are back on the network, but this feature still needs to be tested thoroughly)

I built it to time the kids on our school MTB team. One coach sends the riders at the top, and a parent or another coach waits at the bottom with their phone. It had to be dead simple, work with any device, any group, anywhere. 

I made a demo here: https://youtube.com/shorts/JhBg5TlocEw

Just watched the demo vid, and this app is so sick. Seems like a perfect solution for simple but accurate times runs with the homies, and I love that you thought of the sync feature for all those MTB spots with bad or dubious cell service. Want to get out there and do some EZ racing now.

I had the same problem, so I switched to using a GPS tracking app on my phone (I use TrailSense — it auto-detects runs and shows each lap time as soon as you finish). No need to tap anything mid-ride. I’m on verizon wireless and usually get solid signal on the trails, so the tracking stays accurate. Super simple setup and way less hassle than stopping a watch every run.

I use a sundial to time my downhill runs. That means I don’t care how long each run takes and as long as I’m in one piece I don’t care about the time.