The Analyzer Presents: Top Fuel Diet Series – Handlebars etc.

Looking at ways to cut weight on this bike, I first focused on items I wanted to change anyways after riding and racing the bike for a few months and saving weight when I upgraded.  My Trek Top Fuel came with a nice set of carbon bars, but they were only 690mm wide.  I say “only” as many people are going wider, much wider than that now, even on Cross Country race bikes.  Starting at 23.66 pounds for this go round, let’s see what we can do to save weight while going wider.

I had run 720mm bars in the past and really liked how they felt for me in the places I ride most often.  Not that I’ve tried every different combination of rise and sweep, but I haven’t had issues with zero rise and 9 degrees of sweep so I went with that.  The guys over at Marathon MTB really like the Mt Zoom line out of the UK, so I rolled the dice and ordered a couple of their 720mm Carbon flat bars for my Top Fuel and singlespeed so I’d have the same cockpit in each.  With an advertised weight under 140g, I was a little leery of how they’d hold up, so I installed them on my rigid single speed a few months ago.  

After hundreds of miles of suspensionless banging around with no issues, I decided they were tough enough to put on the race bike.  Putting the new handlebars on the scale showed an actual weight of 138g which is hard to beat for a 720mm bar.  The old Bontrager Pro 690mm bars weighed in at 179g, so going wider here actually ended up saving 41g.  While not the most cost effective weight reduction method thus far at over $2 per gram saved (depending on exchange rate at time of ordering), I was glad I didn’t end up adding weight by adding 30mm to the handlebar width.  


While I had the front end apart, I wanted to address the long steer tube.  While the “smokestack” may be useful for holding donuts, it looks pretty lame, and of course that extra steer tube (and accompanying spacers above the stem) have to weigh something, right?  So out comes the hacksaw, measure twice, cut once and I had trimmed the steer tube to the right length.

That small length of steerer tube was only 8g, but it cost nothing and looks much better right? Combined with removing two carbon spacers the total weight savings for this trim comes to 15g.


One last component which many people don’t think about is the top cap and bolt. How much weight can possibly be there?  Well, I decided to find out.  Pulling the stock Carbon top cap and Steel bolt showed that weighing in at 15g.  While not the biggest area for shaving weight, I figured I could do something with that.  So I had ordered a Mt Zoom Aluminum top cap & bolt combo when I ordered the bars from the guys at  

On my scale this came in at 5g, so a savings of 10g for something that basically just gives a little tension to your headset and keeps dirt out of your steerer. Not bad!

At the end of the day I have a more comfortable feel on the bike with wider bars, better looking front end without that smoke stack there for holding donuts, and saved 66 grams bringing us down to 23.48 pounds.  With ORAMM right around the corner, we’ve got a couple more upgrades on tap to see how much lower we can go…stay tuned!





Part Weight Difference Price $/gram
Hylix 31.8×400 Carbon Seatpost (eBay) 182g 89g $54 $0.61 / g
Carbon 34.9mm Clamp (eBay) 12g 17g $20 $1.18 / g
2x Ashima Ai2 Rotors 139g 84g $40 $0.48 / g
Delete Remote Lockout 0g 118g $0 N/A
Mt Zoom 720mm Flat Bars 138g 41g $90 $2.20 / g
Trim Steerer 0g 15g $0 N/A
Mt Zoom Top Cap 5g 10g $10 $2 / g
Total 285g $160 $0.56 / g


Leave a Reply