Introduction
I was recently in Anchorage, Alaska on two separate trips and had a chance to go on daily rides on a selection of fatbikes. The bikes included EndoRando's personal Ti 907, his personal Wildfire, a loaner Alu 907, and a loaner Ti Fatback. We had daylight rides and night rides in a variety of snow conditions including fast hardpack, packed powder over hardpack, and in a couple of inches of freshly fallen fluff. The trails were a mix of inter-urban greenbelt routes, groomed multiuse/ski trails, and plenty of narrow winding singletrack through the forest and muskeg. One thing I never saw was dirt. Just snow, and lots of it. The bikes had varying cockpit layouts, though most were similar enough to get comfortable when swapping bikes. Most had roughly similar wheel setups (70-80 mm rims with Endomorph tires) with the one exception being the Alu 907 that had 100mm rims and Spyder tires. What follows are my impressions of the bikes. I will spend the most time describing the bikes I rode the most; the Ti 907 and the Ti Fatback (with about 6 rides each). I had 1 ride on the Wildfire and 2 rides on the Alu 907. I spent about 12 hours total spread across the 4 bikes. I did a few solo rides when I (obviously) only took one bike out, but most rides were with EndoRando, and some other folks joined us on various outings. Rando and I are the same height, almost the exact same inseam, and both ride Time pedals so we could swap bikes instantly on the fly and do same-day, same-trail comparisons. I will break my thoughts down into a number of categories covering what I think are the most important design and performance aspects for snowbikes. I own a Pugsley set up with Large Marge rims and a Maverick SC32, and while I have a lot of miles on it on sand and snow, I probably won't mention it much since I didn't have it along for minute-to-minute comparisons with the other bikes. These things are best done with the experience fresh in your mind. I should also mention that the Wildfire was an older model with the 83mm BB shell, so I don't know how directly it compares with the current offerings from Wildfire, but it was a very nice riding bike regardless of age. I also went by Speedway and begged them repeatedly for an Aluminum Fatback, but none were to be had. Alas. Anyway, on with the show...
The bikes (this is a gif showing each frame for 3 seconds, it loops):
Geometry/Handling
With the quality of the ride it offered, the Fatback Ti wins this category, no contest. It offers the best acceleration, it's the easiest to maintain speed on, and it offers neutral and balanced handling in all conditions, not to mention its great climbing and descending characteristics. When swapping between models, both Rando and I would come back to the Fatback and always feel the most at home on it, and we both remarked that "it felt like a Turner" (which is high praise coming from a pair of Homers). The Ti 907 was a real handful with the original Black Sheep fork installed, which was a real surprise given how similar the published geometry numbers were to the Fatback (Ti 907: 70.0 deg HA, Ti Fatback: 69.5 deg HA). The Ti 907 was demanding and twitchy in the steering department, and even when given close and concentrated attention it was still hard to keep on really narrow packed trails. I thought the fast handling would be a benefit on climbs or on slow dicey technical sections, but it just seemed to result in oversteering. The difference between the two bikes was immediately apparent when Rando and I swapped back and forth during a couple of rides, exchanging bikes every 15-20 minutes. Rando was already used to his Ti 907 and had it dialed in for himself, and yet he preferred the handling of the Fatback. We swapped out the stock 450 mm A-C Black Sheep fork for a taller fork on his Ti 907, and this helped the steering and front-end behavior quite a bit. It tamed the overly-fast handling and made the bike feel long and stable. It went from feeling nervous to being a pleasure to motor on the flats. It should be noted that Rando's fork had a 135 mm front hub spacing which was different than two fellow riders who ordered their frames at the same time (they both got 100 mm spaced forks) and they did not report the same handling issues, so there may be something whack with Rando's stock fork. Fork rake and offset will affect trail, and I don't know how these values compared. Though the handling on the Ti 907 improved a lot with the taller fork, the Fatback still had a slight edge in most categories. The Fatback still offered a more lively and spirited ride, possibly due to the shorter wheelbase and lighter weight (about 2 pounds less than the Ti 907 with our builds, see below) but it also still had more natural, neutral, and intuitive trail manners. Rando, the owner of the Ti 907, seemed to broadly agree on all these points though he wanted to find some more narrow singletrack with climbs to make a final determination. I thought the Fatback reacted better to small weight shifts to coax traction or flotation from uncooperative snow surfaces, and I found it generally made riding easier and more fun.
The Alu 907 was a very nice handling bike. It offered a lot positive ride characteristics though it seemed to lack the refined material feel of both the Ti bikes. There may be a placebo effect working here if I think I can feel the Ti's characteristics when floating along on 4 inch tires inflated to under 10 psi and riding over soft surfaces. Especially since the Alu 907 had very different wheels (100mm rims, Spyder tires) than the Ti bikes (70-80mm rims, Endomorph tires). The Alu 907 also had considerably less expensive components, which can affect the overall perception of the bike. We never got a chance to trade out the 100mm rims on the Alu 907 for something lighter and narrower for a more direct comparison to the other frames, but we were still plenty happy with the bike's handling even with the hefty hoops. The Alu 907's head angle seemed just about right (despite the published numbers matching the geo of the Ti 907 just about down to the last measurement) and overall it offered a solid, capable, fun and forgiving ride. If I were a budget-minded buyer in the market right now, among the bikes we rode I would not hesitate to grab one of these. I really liked a lot of the design aspects of the Alu 907 over my current Pugsley like the vertical rear dropouts, corrosion-proof frame material, and the nice ano finish. This one is a winner.
The Wildfire also rode very nicely and had a similar feel to the Alu 907 and kept pace beautifully with the Ti 907 but had a slightly more neutral and stable steering manner than the Ti 907 (with the stock Black Sheep fork). With the taller fork, the Ti 907 had a longer, and more stretched out ride feeling (think 'stable wheelbase') than either the Alu 907 or the Wildfire but otherwise steered similarly well. Once we got the forks sorted out, there really wasn't a bad bike in the bunch, and despite the Wildfire being one of Mark's older creations, it did not feel at all long in the tooth and had every bit as much to offer in terms of ride quality and handling prowess as the newer brands on the scene.
Standover
I have never been particularly stuck on the issue of standover, but if you find yourself on a barely rideable trail of powder or punchy crust, and you end up dabbing repeatedly and having to remount every 20 or 50 feet, you will come to appreciate generous standover in a big way. We rode some trails with a packed tread area about two or three tire-widths wide, and with marginal traction. We weaved off the packed tread into the fluff over and over again necessitating unclipping, getting straightened out, and pedal-kicking to get back into the saddle. The snow just outside the trail tread was deep and soft, so when you unclipped and your foot landed off the side of the trail it sank in a couple of inches below the packed trail tread where the bike stood. In these conditions, the amount of standover available becomes painfully (pun intended) obvious.
Standover can be helped or hurt by where the cables are routed on the top tube, with most builders opting to run them on top of the top tube. I have to admit that I fail to see the reason why this is so popular. Perhaps it is so you can carry the bike without the cables digging into your shoulder, a la a cyclocross carry, but most folks who dismount due to snow conditions tend to push their fatbikes, not carry them long distances. I also thought it may be due to interference with front triangle frame bags, but in my opinion running the cables under the top tube makes more sense even in this scenario. In any case, how the cables are routed coupled with how low the top tube sits can make all the difference in soft conditions. All the bikes with the less-than-generous standover (which was most of them) had me resting on the top tube with every stop, and I don't exactly have short legs. The Fatback, however, was the lone bike that never was in the way, and with the cables routed under the top tube I never felt like I was being threatened with a zip-tie vasectomy (though the cable guide braze-ons on the Fatback do have some frighteningly sharp edges). The Ti Fatback appears to use a short seat tube with a long top tube in its sizing scheme, so while I normally would want a size large frame (~24" top tube), the medium Fatback with its 23.8" was perfect. Even Rando, coming off his large 907 seemed happy on the medium Fatback. The exposed length of seatpost was the only concern.
Most of the snow bikes use pretty tall head tubes giving a nice, upright position without resorting to a million stem spacers (the older Wildfire was the exception, but it also seemed to have a taller fork axle to crown so the result was the same). To support the tall head tube most bikes weld the top tube pretty high on the head tube, which further reduces the standover clearance. The Fatback attaches well below the top of the head tube, which looks pretty weird in my opinion, but gives the bike another ~1 inch of clearance. All the models aside from the Fatback had similar to top tube heights and cable routing. If those other bikes did something to lower their top tubes and get the cables down and out of the way it sure would be nice. I think the swooping top tube on the Faback is pretty ugly, but I fully agree with the functional intent of the design. In order of standover clearance (from best to worst) were the Fatback Ti followed by the Alu 907, then the Ti 907, and last was the Wildfire. For a very rough comparison of the frame layouts, refer back to the animated gif image at the beginning of this post.
Climbing Performance
This was so dependent on tire pressure, gear choice, rider skill and whether the rider was feeling spunky or not, it is hard to compare bikes without taking a digital tire pressure gauge and psychiatrist along and doing repeated runs up a slope. I will say that all the bikes did very nicely in this category, but I would also say the longer chainstays on the Ti 907 did seem to keep the front end of the bike down when there was enough traction to scurry up a really steep incline. You can keep your weight on the nose of the saddle and not have spend as much energy finding that sweet spot between having the front wheel pop up or losing traction in the back. Overall, all the bikes exhibited good climbing performance though the lighter weight of the Ti Fatback may have been one of the reasons why it seemed to climb with a smidge more ease.
As long as we are on the subject of weights, here are the complete bikes we rode and frame weights (thanks, Rando & IPA Rider):
The 100 mm rims on the Alu 907 let us run very low pressure with scant casing deflection and the big contact patch and cushy ride made motoring over chop or up hills pretty darn nice, despite the extra weight. Again, the Alu 907 felt different than the Ti 907 despite the geometries nominally matching and the stock forks having the same A-C measurement. This may have been due to the gyroscopic effect from the Alu 907's considerably heavier wheels. A note on the 100mm rims- at any given time, they only seemed a little slower and heavier than their lighter/narrower counterparts, but there seemed to be a cumulative effect where after a while the added weight wore the rider down. In tempo sections with quick ups and downs or with repeated accelerations like when slogging through snow that shifts under the tire tread, these rims do slowly sap your strength.
Frame-Tire Clearance
Both the Ti frames definitely had the advantage here, with the Ti 907 coming out on top. I am hopeful that in the future someone might offer a ~4.5" tire, and I personally would like the option of running 100 mm rims. Both the Ti 907 and Ti Fatback had ample room between the tire sidewall and the stays to accommodate the largest current common tire/rim combo (100mm/Endomorph) and possibly even have a bit of room for the tire to grow. The Alu 907 was awfully tight when shod with the 100mm rims and the Spider tires. Where the tire passed through the chainstays I could see the ano was getting polished, and while riding and watching the wheel flex there was scant daylight between the sidewall and chainstay at times. If you weren't planning on running a 100 mm rim in back however, then this would not be a concern and the Alu 907 offers plenty of clearance with the more standard 65-80mm rims, and is certainly comparable to the Wildfire and Pugsley in terms of clearance. It's true that 100mm rims are pretty extreme at this point, and they are heavy enough most folks would not want to run them unless the conditions really demanded them. But I would not be surprised if in the future someone came out with a heavily drilled single wall rim wider than the current 70-80 mm offerings that would open the ~100 mm rim class up to mere mortals. The Wildfire offered plenty of frame-tire clearance with the 70 mm rims mounted up and would certainly take 80's with aplomb.
Here are the widths in millimeters at the point where the widest part of the tire casing passes through the stays (chain stay / seat stay):
Drivetrain-Tire Clearance, and Chainline
This design aspect can be just as important as the frame/tire clearance, depending on what rims you want to run. You can't run a big tire/rim combo just because the frame allows it if the chain doesn't also clear the tire. Some bikes address this possible chain-tire interference by running an offset rear triangle (like the Alu 907, Wildfire, and Pugsley) or use a widely spaced, symmetrical rear end (like the Ti 907 and Ti Fatback). All the offset rear triangles should be roughly similar in this regard because they all use the same offset strategy: a 135 mm hub shifted 17.5 mm to the drive side, giving a driveline that approximates a 170 mm rear axle spacing. The only bike we rode with 100 mm rims was the Alu 907, and I have to say the drivetrain clearance was really quite impressive. Even in the 22t granny/32t cassette combo (and this was with a full 9-speed cassette), there was a solid 3 mm clearance between the tire and the chain. The Alu 907 equals no drivetrain worries, though at times there was some tire-frame contact as mentioned above. The other offset bikes should theoretically offer similar chain-tire clearance, but without mounting a 100 mm rim on them I cannot state this as a fact. All the rear offset bikes (the Alu 907, Wildfire, and also the Pugsley) have very respectable chainlines with the middle chainring lining up nominally with the middle cog of the cassette. You could run into some small deviations from this depending on your choice of cranks and bottom brackets, but the offset rear triangles seem like a very good strategy for getting a desirable chainline and have the added (and not inconsiderable) bonus of allowing you to run any standard rear disc hub. Very, very nice.
I have to say the chainline on Rando's Ti 907 is not a very pretty sight. If someone wants a long-winded technical explanation I can post one, but suffice it to say the combination of the poorly spaced King rear hub (King's fault) and the slightly narrow rear dropout spacing on the Ti 907 (relative to the slightly wider Fatback) results in a less than optimal chainline. I often like to climb in the middle chainring and the largest rear cog, and the cross-chaining on the Ti 907 in this gear was pretty extreme despite the fact that Rando had dropped the smallest cog on his cassette, spaced the cassette out, and so is only running 8 gears. Basically, the middle chainring lines up with the second to last (smallest) cassette cog. This misalignment would be corrected by about one cog spacing by running a Hadley 160 mm rear hub. On the Ti Fatback (with a Hadley rear hub), the middle chainring lined up exactly with the center of the cassette (which had 9 cogs). I'm not sure if Speedway's custom Fifteen G cranks were helping out in some way, but the chainline was perfect. We did not put a 100mm rim on the Fatback so I can't comment on how that bike's chain would clear the tire, but I did check out a Ti 907 with 100mm rims and a full 9 speed cassette, and when I shifted it into the lowest gear the chain had to bend around the tire significantly to travel from the cassette to the chainrings (this was with a Hadley hub and RaceFace Atlas cranks). I personally feel the rear end of the Ti 907 had the most room for improvement out of all the bikes we rode.
As a thumbnail reference, here are the drivetrain specs by the numbers:
Aesthetics
Ok, I know this is personal and subjective, but I don't tend to hold back on my opinions so why stop now? The Ti 907 nailed the other bikes' nipples to the wall and stole their girlfriends in this department, no question. It is simply an incredibly beautiful bike in every way. The Ti tubing is HUGE, the welds perfect, and the proportions endlessly attractive. On the other end of the spectrum (in my opinion, anyway) was the Ti Fatback. I have to be honest here and say I think the Lynskey signature design features (curved and lowered top tube, and helical downtube) are sort of ugly and look a bit gimmicky. I don't doubt they offer real performance benefits (actually I know the curved top tube provides a benefit by the standover clearance being nothing short of amazing) but the look just rubs me the wrong way. It looks like someone forgot it was on the roof rack when they tried to pull into the garage. 'Nuff said. Otherwise the brushed Ti on both bikes is beautiful, and both have nice welds, machining, and detail work. I am going to reserve judgment on the Alu 907 we rode since someone obviously made it as hideous as possible in order to be able to recognize it from low earth orbit. I can only assume that someone who is not colorblind building one of these would come up with nicer looking results. Anyway, the ano was durable and beautiful, I liked the gussets in key spots, the welds were uniform and thick, and overall the construction seemed top-notch. The Wildfire was a very pretty bike with a custom iridescent metal-flake purplish color and I especially liked the crazy fat fork legs that balanced nicely with big tires (though 100 mm front hub spacing needs to be banned on fatbikes- getting a big rim and tire out past the brake caliper sucks!).
Ginormous props to EndoRando for playing trail guide, wrench, chauffeur, and all around riding bud for the demo. Also a HUGE thanks to Chain Reaction Cycles and Speedway Cycles for letting us take their babies out and beat them.
Manufacturer websites for specs, geometry, and pricing info:
Some more shots of each bike (thanks, Rando):
Alu 907:
Ti 907:
Fatback Ti:
Wildfire:
I was recently in Anchorage, Alaska on two separate trips and had a chance to go on daily rides on a selection of fatbikes. The bikes included EndoRando's personal Ti 907, his personal Wildfire, a loaner Alu 907, and a loaner Ti Fatback. We had daylight rides and night rides in a variety of snow conditions including fast hardpack, packed powder over hardpack, and in a couple of inches of freshly fallen fluff. The trails were a mix of inter-urban greenbelt routes, groomed multiuse/ski trails, and plenty of narrow winding singletrack through the forest and muskeg. One thing I never saw was dirt. Just snow, and lots of it. The bikes had varying cockpit layouts, though most were similar enough to get comfortable when swapping bikes. Most had roughly similar wheel setups (70-80 mm rims with Endomorph tires) with the one exception being the Alu 907 that had 100mm rims and Spyder tires. What follows are my impressions of the bikes. I will spend the most time describing the bikes I rode the most; the Ti 907 and the Ti Fatback (with about 6 rides each). I had 1 ride on the Wildfire and 2 rides on the Alu 907. I spent about 12 hours total spread across the 4 bikes. I did a few solo rides when I (obviously) only took one bike out, but most rides were with EndoRando, and some other folks joined us on various outings. Rando and I are the same height, almost the exact same inseam, and both ride Time pedals so we could swap bikes instantly on the fly and do same-day, same-trail comparisons. I will break my thoughts down into a number of categories covering what I think are the most important design and performance aspects for snowbikes. I own a Pugsley set up with Large Marge rims and a Maverick SC32, and while I have a lot of miles on it on sand and snow, I probably won't mention it much since I didn't have it along for minute-to-minute comparisons with the other bikes. These things are best done with the experience fresh in your mind. I should also mention that the Wildfire was an older model with the 83mm BB shell, so I don't know how directly it compares with the current offerings from Wildfire, but it was a very nice riding bike regardless of age. I also went by Speedway and begged them repeatedly for an Aluminum Fatback, but none were to be had. Alas. Anyway, on with the show...
The bikes (this is a gif showing each frame for 3 seconds, it loops):
Geometry/Handling
With the quality of the ride it offered, the Fatback Ti wins this category, no contest. It offers the best acceleration, it's the easiest to maintain speed on, and it offers neutral and balanced handling in all conditions, not to mention its great climbing and descending characteristics. When swapping between models, both Rando and I would come back to the Fatback and always feel the most at home on it, and we both remarked that "it felt like a Turner" (which is high praise coming from a pair of Homers). The Ti 907 was a real handful with the original Black Sheep fork installed, which was a real surprise given how similar the published geometry numbers were to the Fatback (Ti 907: 70.0 deg HA, Ti Fatback: 69.5 deg HA). The Ti 907 was demanding and twitchy in the steering department, and even when given close and concentrated attention it was still hard to keep on really narrow packed trails. I thought the fast handling would be a benefit on climbs or on slow dicey technical sections, but it just seemed to result in oversteering. The difference between the two bikes was immediately apparent when Rando and I swapped back and forth during a couple of rides, exchanging bikes every 15-20 minutes. Rando was already used to his Ti 907 and had it dialed in for himself, and yet he preferred the handling of the Fatback. We swapped out the stock 450 mm A-C Black Sheep fork for a taller fork on his Ti 907, and this helped the steering and front-end behavior quite a bit. It tamed the overly-fast handling and made the bike feel long and stable. It went from feeling nervous to being a pleasure to motor on the flats. It should be noted that Rando's fork had a 135 mm front hub spacing which was different than two fellow riders who ordered their frames at the same time (they both got 100 mm spaced forks) and they did not report the same handling issues, so there may be something whack with Rando's stock fork. Fork rake and offset will affect trail, and I don't know how these values compared. Though the handling on the Ti 907 improved a lot with the taller fork, the Fatback still had a slight edge in most categories. The Fatback still offered a more lively and spirited ride, possibly due to the shorter wheelbase and lighter weight (about 2 pounds less than the Ti 907 with our builds, see below) but it also still had more natural, neutral, and intuitive trail manners. Rando, the owner of the Ti 907, seemed to broadly agree on all these points though he wanted to find some more narrow singletrack with climbs to make a final determination. I thought the Fatback reacted better to small weight shifts to coax traction or flotation from uncooperative snow surfaces, and I found it generally made riding easier and more fun.
The Alu 907 was a very nice handling bike. It offered a lot positive ride characteristics though it seemed to lack the refined material feel of both the Ti bikes. There may be a placebo effect working here if I think I can feel the Ti's characteristics when floating along on 4 inch tires inflated to under 10 psi and riding over soft surfaces. Especially since the Alu 907 had very different wheels (100mm rims, Spyder tires) than the Ti bikes (70-80mm rims, Endomorph tires). The Alu 907 also had considerably less expensive components, which can affect the overall perception of the bike. We never got a chance to trade out the 100mm rims on the Alu 907 for something lighter and narrower for a more direct comparison to the other frames, but we were still plenty happy with the bike's handling even with the hefty hoops. The Alu 907's head angle seemed just about right (despite the published numbers matching the geo of the Ti 907 just about down to the last measurement) and overall it offered a solid, capable, fun and forgiving ride. If I were a budget-minded buyer in the market right now, among the bikes we rode I would not hesitate to grab one of these. I really liked a lot of the design aspects of the Alu 907 over my current Pugsley like the vertical rear dropouts, corrosion-proof frame material, and the nice ano finish. This one is a winner.
The Wildfire also rode very nicely and had a similar feel to the Alu 907 and kept pace beautifully with the Ti 907 but had a slightly more neutral and stable steering manner than the Ti 907 (with the stock Black Sheep fork). With the taller fork, the Ti 907 had a longer, and more stretched out ride feeling (think 'stable wheelbase') than either the Alu 907 or the Wildfire but otherwise steered similarly well. Once we got the forks sorted out, there really wasn't a bad bike in the bunch, and despite the Wildfire being one of Mark's older creations, it did not feel at all long in the tooth and had every bit as much to offer in terms of ride quality and handling prowess as the newer brands on the scene.
Standover
I have never been particularly stuck on the issue of standover, but if you find yourself on a barely rideable trail of powder or punchy crust, and you end up dabbing repeatedly and having to remount every 20 or 50 feet, you will come to appreciate generous standover in a big way. We rode some trails with a packed tread area about two or three tire-widths wide, and with marginal traction. We weaved off the packed tread into the fluff over and over again necessitating unclipping, getting straightened out, and pedal-kicking to get back into the saddle. The snow just outside the trail tread was deep and soft, so when you unclipped and your foot landed off the side of the trail it sank in a couple of inches below the packed trail tread where the bike stood. In these conditions, the amount of standover available becomes painfully (pun intended) obvious.
Standover can be helped or hurt by where the cables are routed on the top tube, with most builders opting to run them on top of the top tube. I have to admit that I fail to see the reason why this is so popular. Perhaps it is so you can carry the bike without the cables digging into your shoulder, a la a cyclocross carry, but most folks who dismount due to snow conditions tend to push their fatbikes, not carry them long distances. I also thought it may be due to interference with front triangle frame bags, but in my opinion running the cables under the top tube makes more sense even in this scenario. In any case, how the cables are routed coupled with how low the top tube sits can make all the difference in soft conditions. All the bikes with the less-than-generous standover (which was most of them) had me resting on the top tube with every stop, and I don't exactly have short legs. The Fatback, however, was the lone bike that never was in the way, and with the cables routed under the top tube I never felt like I was being threatened with a zip-tie vasectomy (though the cable guide braze-ons on the Fatback do have some frighteningly sharp edges). The Ti Fatback appears to use a short seat tube with a long top tube in its sizing scheme, so while I normally would want a size large frame (~24" top tube), the medium Fatback with its 23.8" was perfect. Even Rando, coming off his large 907 seemed happy on the medium Fatback. The exposed length of seatpost was the only concern.
Most of the snow bikes use pretty tall head tubes giving a nice, upright position without resorting to a million stem spacers (the older Wildfire was the exception, but it also seemed to have a taller fork axle to crown so the result was the same). To support the tall head tube most bikes weld the top tube pretty high on the head tube, which further reduces the standover clearance. The Fatback attaches well below the top of the head tube, which looks pretty weird in my opinion, but gives the bike another ~1 inch of clearance. All the models aside from the Fatback had similar to top tube heights and cable routing. If those other bikes did something to lower their top tubes and get the cables down and out of the way it sure would be nice. I think the swooping top tube on the Faback is pretty ugly, but I fully agree with the functional intent of the design. In order of standover clearance (from best to worst) were the Fatback Ti followed by the Alu 907, then the Ti 907, and last was the Wildfire. For a very rough comparison of the frame layouts, refer back to the animated gif image at the beginning of this post.
Climbing Performance
This was so dependent on tire pressure, gear choice, rider skill and whether the rider was feeling spunky or not, it is hard to compare bikes without taking a digital tire pressure gauge and psychiatrist along and doing repeated runs up a slope. I will say that all the bikes did very nicely in this category, but I would also say the longer chainstays on the Ti 907 did seem to keep the front end of the bike down when there was enough traction to scurry up a really steep incline. You can keep your weight on the nose of the saddle and not have spend as much energy finding that sweet spot between having the front wheel pop up or losing traction in the back. Overall, all the bikes exhibited good climbing performance though the lighter weight of the Ti Fatback may have been one of the reasons why it seemed to climb with a smidge more ease.
As long as we are on the subject of weights, here are the complete bikes we rode and frame weights (thanks, Rando & IPA Rider):
- FatBack 28.9 lbs (~3.5 lbs frame for 18")
- Ti 907 30.4 lbs (~3.3 lbs for 17" frame)
- WildFire 31.6 lbs (~4.6 lbs frame for 19")
- Al 907 (without pedals) 35.8 lbs (~3.7 lbs frame for 19")
- Pugsley *Not Demoed* (~5.7 lbs frame for 18")
The 100 mm rims on the Alu 907 let us run very low pressure with scant casing deflection and the big contact patch and cushy ride made motoring over chop or up hills pretty darn nice, despite the extra weight. Again, the Alu 907 felt different than the Ti 907 despite the geometries nominally matching and the stock forks having the same A-C measurement. This may have been due to the gyroscopic effect from the Alu 907's considerably heavier wheels. A note on the 100mm rims- at any given time, they only seemed a little slower and heavier than their lighter/narrower counterparts, but there seemed to be a cumulative effect where after a while the added weight wore the rider down. In tempo sections with quick ups and downs or with repeated accelerations like when slogging through snow that shifts under the tire tread, these rims do slowly sap your strength.
Frame-Tire Clearance
Both the Ti frames definitely had the advantage here, with the Ti 907 coming out on top. I am hopeful that in the future someone might offer a ~4.5" tire, and I personally would like the option of running 100 mm rims. Both the Ti 907 and Ti Fatback had ample room between the tire sidewall and the stays to accommodate the largest current common tire/rim combo (100mm/Endomorph) and possibly even have a bit of room for the tire to grow. The Alu 907 was awfully tight when shod with the 100mm rims and the Spider tires. Where the tire passed through the chainstays I could see the ano was getting polished, and while riding and watching the wheel flex there was scant daylight between the sidewall and chainstay at times. If you weren't planning on running a 100 mm rim in back however, then this would not be a concern and the Alu 907 offers plenty of clearance with the more standard 65-80mm rims, and is certainly comparable to the Wildfire and Pugsley in terms of clearance. It's true that 100mm rims are pretty extreme at this point, and they are heavy enough most folks would not want to run them unless the conditions really demanded them. But I would not be surprised if in the future someone came out with a heavily drilled single wall rim wider than the current 70-80 mm offerings that would open the ~100 mm rim class up to mere mortals. The Wildfire offered plenty of frame-tire clearance with the 70 mm rims mounted up and would certainly take 80's with aplomb.
Here are the widths in millimeters at the point where the widest part of the tire casing passes through the stays (chain stay / seat stay):
- Ti 907: 121 / 125
- Ti Fatback: 119 / 122
- Alu 907: 111 / 111
- Wildfire: 111 / 116
- Pugsley: 112 / 115
Drivetrain-Tire Clearance, and Chainline
This design aspect can be just as important as the frame/tire clearance, depending on what rims you want to run. You can't run a big tire/rim combo just because the frame allows it if the chain doesn't also clear the tire. Some bikes address this possible chain-tire interference by running an offset rear triangle (like the Alu 907, Wildfire, and Pugsley) or use a widely spaced, symmetrical rear end (like the Ti 907 and Ti Fatback). All the offset rear triangles should be roughly similar in this regard because they all use the same offset strategy: a 135 mm hub shifted 17.5 mm to the drive side, giving a driveline that approximates a 170 mm rear axle spacing. The only bike we rode with 100 mm rims was the Alu 907, and I have to say the drivetrain clearance was really quite impressive. Even in the 22t granny/32t cassette combo (and this was with a full 9-speed cassette), there was a solid 3 mm clearance between the tire and the chain. The Alu 907 equals no drivetrain worries, though at times there was some tire-frame contact as mentioned above. The other offset bikes should theoretically offer similar chain-tire clearance, but without mounting a 100 mm rim on them I cannot state this as a fact. All the rear offset bikes (the Alu 907, Wildfire, and also the Pugsley) have very respectable chainlines with the middle chainring lining up nominally with the middle cog of the cassette. You could run into some small deviations from this depending on your choice of cranks and bottom brackets, but the offset rear triangles seem like a very good strategy for getting a desirable chainline and have the added (and not inconsiderable) bonus of allowing you to run any standard rear disc hub. Very, very nice.
I have to say the chainline on Rando's Ti 907 is not a very pretty sight. If someone wants a long-winded technical explanation I can post one, but suffice it to say the combination of the poorly spaced King rear hub (King's fault) and the slightly narrow rear dropout spacing on the Ti 907 (relative to the slightly wider Fatback) results in a less than optimal chainline. I often like to climb in the middle chainring and the largest rear cog, and the cross-chaining on the Ti 907 in this gear was pretty extreme despite the fact that Rando had dropped the smallest cog on his cassette, spaced the cassette out, and so is only running 8 gears. Basically, the middle chainring lines up with the second to last (smallest) cassette cog. This misalignment would be corrected by about one cog spacing by running a Hadley 160 mm rear hub. On the Ti Fatback (with a Hadley rear hub), the middle chainring lined up exactly with the center of the cassette (which had 9 cogs). I'm not sure if Speedway's custom Fifteen G cranks were helping out in some way, but the chainline was perfect. We did not put a 100mm rim on the Fatback so I can't comment on how that bike's chain would clear the tire, but I did check out a Ti 907 with 100mm rims and a full 9 speed cassette, and when I shifted it into the lowest gear the chain had to bend around the tire significantly to travel from the cassette to the chainrings (this was with a Hadley hub and RaceFace Atlas cranks). I personally feel the rear end of the Ti 907 had the most room for improvement out of all the bikes we rode.
As a thumbnail reference, here are the drivetrain specs by the numbers:
- Ti 907: BB width- 100 mm, rear dropout spacing- 160 mm symmetrical
- Ti Fatback: BB width- 100 mm, rear dropout spacing- 165 mm symmetrical
- Alu 907: BB width- 100 mm, rear dropout spacing- 135 mm with 17.5 mm driveside offset
- Wildfire: BB width- 83 mm**, rear dropout spacing- 135 mm with 17.5 mm driveside offset
- Pugsley: BB width- 100 mm, rear dropout spacing- 135 mm with 17.5 mm driveside offset
Aesthetics
Ok, I know this is personal and subjective, but I don't tend to hold back on my opinions so why stop now? The Ti 907 nailed the other bikes' nipples to the wall and stole their girlfriends in this department, no question. It is simply an incredibly beautiful bike in every way. The Ti tubing is HUGE, the welds perfect, and the proportions endlessly attractive. On the other end of the spectrum (in my opinion, anyway) was the Ti Fatback. I have to be honest here and say I think the Lynskey signature design features (curved and lowered top tube, and helical downtube) are sort of ugly and look a bit gimmicky. I don't doubt they offer real performance benefits (actually I know the curved top tube provides a benefit by the standover clearance being nothing short of amazing) but the look just rubs me the wrong way. It looks like someone forgot it was on the roof rack when they tried to pull into the garage. 'Nuff said. Otherwise the brushed Ti on both bikes is beautiful, and both have nice welds, machining, and detail work. I am going to reserve judgment on the Alu 907 we rode since someone obviously made it as hideous as possible in order to be able to recognize it from low earth orbit. I can only assume that someone who is not colorblind building one of these would come up with nicer looking results. Anyway, the ano was durable and beautiful, I liked the gussets in key spots, the welds were uniform and thick, and overall the construction seemed top-notch. The Wildfire was a very pretty bike with a custom iridescent metal-flake purplish color and I especially liked the crazy fat fork legs that balanced nicely with big tires (though 100 mm front hub spacing needs to be banned on fatbikes- getting a big rim and tire out past the brake caliper sucks!).
Ginormous props to EndoRando for playing trail guide, wrench, chauffeur, and all around riding bud for the demo. Also a HUGE thanks to Chain Reaction Cycles and Speedway Cycles for letting us take their babies out and beat them.
Manufacturer websites for specs, geometry, and pricing info:
- 9:Zero:7 Ti and Aluminum frames: Chain Reaction Cycles, Alaska
- Fatback Ti: Speedway Cycles, Alaska
- Wildfire: Wildfire Bike Designs, Alaska
- Pugsley: Surly Bikes
Some more shots of each bike (thanks, Rando):
Alu 907:
Ti 907:
Fatback Ti:
Wildfire: