Review: Vassago OptimusTi Mountain Bike Frame

Vassago only builds big-wheeled bikes, and is best known for their steel single speed frame, the Jabberwocky.  I have been riding one for over three years now, and really like it, so I was sad to see the company go through a rough patch a while back.  But recently Vassago was bought by some former …

Vassago only builds big-wheeled bikes, and is best known for their steel single speed frame, the Jabberwocky.  I have been riding one for over three years now, and really like it, so I was sad to see the company go through a rough patch a while back.  But recently Vassago was bought by some former Vassago sponsored racers, and they are now back in business and pumping out frames, including the long awaited Black Label series: high-end frames made of premium materials and built in the USA.  The OptimusTi is one of those frames and I recently got to spend a few weeks pedaling one around.

Fresh out of the box.


The OptimusTi is a titanium 29er frame, built right here in the USA.  It has sliding dropouts so it can be used as a single speed or set up with gears, and several dropouts are available for all the popular axle standards.  All cable guides to go geared are on the frame, but I chose to set my test frame up as a single speed.  The frame features an oversized 44mm head tube, allowing the use of either a straight or tapered steerer fork.  The rear brake is a post mount, and there’s a real metal badge on the head tube.

Beautiful welds at the bottom bracket, and a beefy chainstay bridge.

My medium frame weighed in at 1980g (4.34lbs) including the seat post clamp and headset cups, but no headset bearings.  After I built it up, my complete bike weighed 22.32lbs, about 3/4 of a pound lighter than the Jabberwocky.  The OptimusTi frame sells for $1,900-$2,100 depending on options.

Burly stays and post mount brake on a slider dropout. My frame had pre-production dropouts; production dropouts will be anodized black.


Vassago has always used a low and long geometry: a low bottom bracket with longer-than-normal top tubes are their signature.  The OptimusTi uses what Vassago calls “FastCat” geometry, vs. the “WetCat” geometry used on the Jabberwocky.  FastCat geometry is a slight adaptation of the WetCat, designed around a 100mm suspension fork instead of an 80mm and features shorter chainstays (I had to take a link out of my chain when building up the bike with all the parts from my Jabberwocky). There’s also slightly less bottom bracket drop.  The seat tube and head tube angles are the same as WetCat–that is to say, a bit more laid back than your average XC 29er.  The full geometry chart can be found on the Vassago website.

Bling bling!

The Ride

Titanium frames of yesteryear have a reputation for being really flexible–too flexible for many riders’ tastes.  The first thing I noticed when I pulled the OptimusTi out of it’s box was the tubing: it’s big.  Every tube is larger than on my Jabberwocky, and the seat and chainstays are especially stout looking–it certainly didn’t look like it would be flexible.  Trail time confirmed my suspicions: this baby is plenty stiff.  I think it actually pedals stiffer than my Jabberwocky, with less side-to-side sway at the bottom bracket when out of the saddle and mashing that single gear up and over a hill.

Riding the OptimusTi at Mistletoe State Park.

Even though the OptimusTi is stiff under pressure, the legendary feel of titanium is still palpable.  The Ti nicely mutes trail buzz and vibrations, making for a very smooth and comfortable ride.  It’s not suspension of course–you still feel all the larger bumps.  But vibrations are tuned out, which improves comfort and reduces fatigue on long rides.  I only had the bike a few weeks, but did manage two pretty long rides, including one metric century and then some.  The longer you spend in the saddle, the more you appreciate and benefit from that smooth ride.


I built my test frame up with a White Brothers Rock Solid rigid carbon fork, which is suspension-corrected for an 80mm travel fork.  The OptimusTi is really designed around a longer fork so most folks will probably build this frame up with a 100mm fork.

Using a shorter fork as I did lowers the front end a bit, steepens the head tube angle, and lowers the bottom bracket a touch as well.  I don’t think everyone would enjoy this setup, but I LOVED it!  It handled fast and absolutely railed corners.  But, I did hit my pedals every now and then thanks to the low bottom bracket, and the handling might have been a bit too nervous for many riders–you really have to pay attention and stay on top of it.  With the longer 100mm suspension fork, or a newer generation 100mm suspension-corrected rigid fork, it would be perfect.  Pedal strikes would happen less often, there would be a bit more stability, but it would still corner well.

The OptimusTi is a corner carving machine with a short fork, but most riders would probably prefer a longer fork and slightly calmer handling.

Compared to my Jabberwocky the most welcomed change is the shorter rear end.  It is much easier to pick the front wheel up with the rear wheel tucked up under you, and the shorter rear end quickens the handling a bit as well, and I found myself clipping the rear tire on obstacles much less often than on my Jabberwocky.

Other Stuff

The build quality on the OptimusTi is top notch.  The finish is even on all the tubes, and the welds are all perfect.  It’s a beautiful frame, and since it’s titanium, it will stay that way forever since titanium doesn’t rust or corrode and there’s no paint to scratch.  The slider hardware is all very nice as well.  It’s a small thing to mention, but I really like the hose guides. Brake hoses snap in place for a perfect fit; you could almost ride it without any zip ties to keep the hose in the guide.

Most bikes wish they had a head tube badge this cool.

The dropouts were easy to adjust and stayed put.  However in general I’m still at odds with slider dropouts.  I prefer the look, simplicity, and lower weight of track-end dropouts like those found on my Jabberwocky.  But, the sliders are easier to live with, and these never gave me any trouble.

One advantage to the sliders is you can take the rear wheel out without futzing with chain tension.  With track ends you have to reduce the tension enough to get the chain off the cog, pull the wheel back and out of the dropouts, and then reset the chain tension when you put the wheel back in.  The other advantage is the brake is always in the same position relative to the hub since it moves with the dropout, so changing gear ratios doesn’t require adjusting the brake caliper.

A SS-specific dropout is also available without a derailleur hanger for a cleaner look.


Vassago has hit a home run with the OptimusTi.  It has all the features of a modern mountain bike combined with the long-admired smooth ride of titanium and exceptional craftsmanship.  The only thing that will keep people away is the price.  It’s not a cheap frame, but I do think it’s a good value in the long run.  It won’t rust or corrode, titanium has an extremely long fatigue life, and the dropout choices and 44mm head tube give you tons of options for building it up however you like.  It could very well be the last hardtail frame you ever need to buy.

Up Next:

The OptimusTi is headed back to Vassago, but they have been kind enough to send me the other Black Label frame to review–the VerHauen, which is a more affordable steel frame, but still built in the USA.  Stay tuned to the Singletracks blog for more details!

Want to learn more?  Hit up the Vassago website right here.

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