Spot Rocker SS compared to Ibis Tranny/T-29

Hey Shadow, just saw this, sorry for late reply.

Yep, got 'em both right now, and love 'em both.

I've been SS'ing for 5 years since I got the Tranny. MTB active for ~15 years. Avid intermediate. Strongly focused on getting up the trails and having (prudent) fun on the way down. Learning more about carving turns correctly since a crash three years ago. FS bike is a Ripley, but it only gets ~5% of my ride time unless we're traveling to ride (So. UT, Sedona, Idaho) in which case Ripley is the main ride on new trails.

My Tranny-29 (Lg) is the light plus-sized Monster Truck. Gates belt SS 39/28. I live in Utah so "PGG" is req'd for me (pre-geezer gearing.) 120 Sid RLC (51 offset) with remote with 1 deg. Angleset and 29/27.5 front/rear mullet, brings HA to 68 degree. Wheels are Ibis 941 (i35) w/Onyx Classic hubs. Tires, XR2 29 x 3.0 and XR2 27.5 x 2.8. RF Next 175, Ritchey carbon bar/stem (90mm), KS Lev C1 dropper, etc. bring weight w/Shimano XTR PD-9120 to 23.5 lbs. The Tranny frame is stiff out of the saddle and goes over lots of stuff up hill and is fast while doing it. It's solid in the turns and my go-to for most of my rides. Plus tires, and tweaks to lower HA has made it a lot more fun in all conditions.

The Spot Carbon Rocker (Lg) is the "sprint" XC bike and my birthday present to myself this year (70 is still pre-geezer, I'm certain). Gates belt 39/26. Fox 120 SC with remote (44 offset). HA is 67. Wheels Ibis 935 (i29) w/Onyx Vesper and Berd spokes. (1526 actual weight, no rim tape.) Tires 29 x 2.35 Racing Ray (front) Racing Ralphs (back). RF Next 170, ENVE bars/stem (60mm), KS Lev Ci 170 dropper. Shimano PD-9120 pedals. Weight is stupid light 20.4 lbs. That was the goal. This sucker flies up hill, geared a bit higher, and carves great going down. I'm torn between the uncanny speed uphill and maybe wanting to throw some 2.5-2.6 tires on and light up the curves a bit more on the downs.

Comparison?

Spot blazes. You think, it goes. Really amazing how fast and easily it climbs and how I can catch FS buddies on the uphills . And, yep, it's in part due to the custom build, although Hardtail Party Steve thought it was really fast as well on a stock build. Somebody more experienced than me on the SS forums should talk about the relationship between bike frame/rotating weight and gearing for uphills. Spot is so fast, you almost don't have time to get out of breath over the hard sections. I know that sounds goofy, but there you have it. Also feels more modern/precise/centered in the carves than the Tranny. And the 170 dropper rocks because it lets you get the seat way out of the way on downhill!

Tranny plussed-up is the go-to for longer and more difficult rides. It's more forgiving and has the cush for 20+ miles and bigger vert (2500' or more, although Spot isn't harsh in any way.). Great bike, always will be. Might try to get a 150 dropper on it with some mod to the seat post so I can lean it over more on turns. BTW - the Tranny frame was 1.5 oz lighter than the Spot. I know composites well and the Tranny build quality is excellent.

Comments on both bikes: I run all belts with about .5" deflection when pushed on lightly. If chainring/cog are aligned right, don't need or want them super tight. For belt "lube" in late summer moondust, I use boron nitride powder, brushed on lightly, every long ride. Works great, very clean. All liquid lubes I've tried collect the dust and belts start creaking. (We also have two Ibis Trans-Fat Gates SS for beaches and trail goofery, so lots of belt experience.)

I'll also say right up front that both bikes have bar ends. Call me a kook, but the extra "gear' is great. Specialized Overendz are light, minimal, and rock, but hard to find. Really nice for varying wrist position too. I've seen other Spot Carbon Rocker reports with similar setup.

Hope this is useful. Lemme know any questions.

Hey Banshee,

I've enjoyed many of your posts and experiences over the years, so cool to get your take!

Yeah, was hesitant to put that in about the climbing. Probably just the thrill of the birthday bike. But it seems everyone SSing runs higher gears than I do, so at times I'm just stoked to get up some stuff without blowing up. But most of the time the Spot does accelerate and fly in a surprising way. Kinda what Steve HTP noted. The Tranny has been known for that as well, but since I plussed it up, it's a different feel, more all terrain animal than greyhound. I guess that the slightly higher gear than the Tranny, and the low rotating weight of the wheelset/tires gets me further in less time without wearing me out unduly. Long climbs are still long climbs, but all the little transitions, rock knobs, etc. are dealt with a little quicker so I can get to the next lower angle section and recover sooner. On the Tranny, the strategy has been to learn how to low-rpm climb like a sloth in places for recovery, then stand on it when I need to and use the big tires to get over stuff, sometimes slowly, sometimes spun up a bit. Less momentum at times, more caterpillar.

We all know the momentum/pacing game is a big part of what makes SS so rewarding. Upper body "rowing" workout is a plus as well.

Lotsa downsides to belt drive, as have been covered before - price, adjustment, not as easy to tweak for your exact gear, large chainring rock bashing. But I like the instant response, the quiet, clean low maintenance (except as noted) and the light weight. I rarely change gear ratio, having found the sweet spot for my local trails and abilities. So it works well for me. No clue how it would work for your MTB or trialsy rides (so cool you have those skills!).

The boron nitride powder is readily available and not very expensive for a multi-year supply: MICROLUBROL 4 oz Hexagonal Boron Nitride hBN Powder FINE 2.5 µ Micron: Amazon.com: Industrial & Scientific
I put it on lightly with a little acid brush. Any brush will do. Just gotta be sure any old gunk on the belt from liquid lubes/dirt has been thoroughly cleaned off. I've never tried it on chains on my FS. Might be a neat experiment. One of the Muc-off formulas claims to have BN in it, but it's a liquid base, so not good for the ultra-fine dust.. So far I've been using it for two years, and it's working well. Still have half the container left. It's white and very clean. Just don't get it on any smooth floor or you will get a local slip hazard big time.

Milo,

My goto is keeping 2.14 ratio which really isn't as tall a gear as some might think however, with cadence range sorted in terms of what is comfortable, can be done for extended periods or distances, it makes all the difference.
The punches... Anticipation and reading the demand of upcoming terrain! This is what really drives the juices... Adrenaline and endorphins are our drugs of choice, so whadda we do, we singlespeed to maximize the release of em, of course!! Oh hells ya, here we go! Mash a moment and settle in for a hella nice cadence and the joy of adrenaline and endorphins is Incoming.

I digress....

The workout is not a workout, it's all about playing bikes, don'tcha know!

The Spot and Ibis do sound very alluring. Getting the gears sorted and being in the saddle... Cruising along and give it the spin up with authority and feel the speed increase handily.

Geometry... That falls in a "what ever feels good to the rider" area.
Sliding dropouts are drama free by comparison to slotted. Think Surly Krampus... Tugs and such can be temperamental.

Thanks for the impressions. I've got my XL Tranny setup with 120 SC, Transfer dropper, and Gates 46x28 right now and have been focusing it more towards XC with slight trail tendencies given my Ripley V2 LS is built to be able to handle the rowdier trails.

Complete build specs here: Tranny 29 Picture and Build Thread
I've since changed out the front tire for a 2.35 Barzo and added a Fox Transfer post. Weighs in at about ~22lbs last I checked since adding the dropper.

Interesting to hear about the Spot Rocker and how it feels on the more sweeping turns. The Tranny (and lesser extent Ripley) have always felt more nimble/twitchey compared to newer bikes given their shorter wheel bases so that makes sense. Highly jealous of your rear wheel with the Vesper hub. I've got a Roval/DT Swiss 240S rear right now that's hard to beat weight wise, but I've been trying to convince myself to take the plunge and build a wheel with the Vesper for silent riding. Hard to commit to when the Tranny is on 142mm rear and would really limit it's usefulness to only that bike.