Full Suspension Bikes and SRMR Finish Rates

Conventional wisdom says that the added complexity of full suspension (or some say any suspension) will reduce their reliability to the point of making them a poor choice for ultra-endurance racing. There are several components to this, and, like so much conventional wisdom, data may contradict the accepted story.

Separating Anecdote from Data

First, I am not talking about long term bikepacking or light touring. Most suspension wants maintenance every 50 hours or so. That’s only a few days of racing, or a couple of weeks of bikepacking. Even pushing that interval by a significant multiple does not make for a practical crossing of a continent. The turning point of this is probably something like tour divide, with the frontrunners finishing in something like 250 hours of riding, enough to put significant wear on suspension, but still within reasonable expectation of it not failing.

I asked AI chatbots about this, and was told that rigid bikes are more likely to finish SRMR.  I asked a couple of friends, who said similar things.  If I took advice at face value, singlespeed and rigid would be the way to go.

Like much of bikepacking doctrine, there is lots of anecdotal lore around failures. In the shop, when I see broken bikes, one of the most popular “just riding along” stories is that the suspension pivot bolt “just fell out”. Since a snug bolt never just falls out, there is always some component of neglecting the gradually loosening bolt to these stories. There are also stories of success as well, but it is difficult to quantify which stories are accurate, and which are more hyperbolic. I am a professional bike mechanic, and my bike will be properly prepped for the race, so the reliability should be a lesser issue for me than for someone who neglects their bike until it breaks.

I brought a full suspension bike last time, it gave me no problems, and I loved the handling. I have ridden an assortment of bikes with anywhere from full suspension down to completely rigid on bikepacking trips, and while each has their advantages, I always appreciate the cushion of a full suspension bike, especially after the first few days. This summer, I rode 200km overnighters on a hardtail, a gravel bike with suspension seatpost, stem, and fork, and on my 120mm front and rear full suspension bike. None of them was bad, but the full suspension bikes sure do reduce my fatigue.

The easy facts are within reach. Tour Divide, SRMR, The Lost Elephant, and others have been won on full suspension mountain bikes. People have likewise withdrawn from the same races on all types of bikes. I wanted to know if the alleged reliability benefit of hardtails would translated to higher finish rates on the SRMR. I set out to quantify the difference if I could.

In my previous article, I was seeking data around equipment and riders scratching. Conveniently for me, suspension data was much easier to come by. The very popular “rigs of SRMR” articles from bikepacking.com, along with a couple of other sources gave me the information about the bikes, while the tracking sites and roster lists were used for finish data. 

What I Found

The data is not as rigorous as I would like, since I don’t have all of the bike data, nor all of the people, but it does definitely show some strong correlations:

For men in their 20s and 30s, bike type does not seem to matter much at all.

For men in their 40s, the finish rate was about 47% on hardtail bikes, about 57% on full suspension bikes

For men in their 50s, the gap in finish rates is massive, about 40% finish on hardtails, and about 62% on full suspension

Note that I did not use women in this data, for two reasons, first, there are fewer women in the race, second, for various reasons, the women’s finishing rate is much greater. I could not find meaningful enough trends in women’s bike selection data to draw conclusions from. I considered trying to ride more like a woman, but I’m a dude, so that may not work that well. I will be listening closely to you, Detours Podcast.

Since I was looking for the kind of data where scratching was attributable to bike choice, I did not include anyone who scratched on day 1-3. The kind of fatigue that would be reduced by having a full suspension bike is not going to show up early, but rather later in the race. Early scratches are frequently illness or injury unrelated to bike choice. I initially tried to make AI do the counting for me, but it didn’t seem to reliably know which bikes were hardtail and which were full suspension. I also did not count rigid bikes, I have pretty much decided to use a suspension fork, and the numbers in recent years are very low.

Conclusion

The conclusion that this brings me to is clear, and I will definitely be riding a full suspension bike since this is the easiest way to improve my statistical chance of finishing. Last time around, I did choose a full suspension bike, and I still scratched, so this is not any kind of improvement from before, just a confirmation of what I already suspected. I personally believe that the improvements I have made in navigation (the. primary cause of my SRMR scratch) are much more important than this bike decision. Most importantly in all of this, bikes are only as good as the rider, and the training that I do and have done will change my odds by much more than bike choice.

Full suspension bikes are most  certainly an advantage, especially at my age.