Fat Boy
07-02-07, 08:04 PM
OK, Here’s my Downtube FS IX review. I got it a couple weeks ago. I have a reasonable amount of bike experience, but I’m not a complete bicycle maniac. The reason I wanted a folder is because I work on racecars which means I travel all the time. When on the road I end up stranded in a hotel a lot. Having a bike that I can take with me gives me access to transportation, gets me some exercise, and keeps me out of the bars!
From the time I opened the box to actually riding the bike was probably less than 15 minutes, and I even read some of the directions! I think the bike looks pretty cool and I was happy with the initial overall looks and finish. The riding position is much better that I expected it to be. The bike is well balanced and handles nicely. The 20” wheels are plenty big enough to be stable. Maybe I could have gotten away with the 16” bike, I don’t know. I did travel on United with the bike in my new Samsonite F’Lite 31 case. I checked it at the curb in Los Angeles. It cost $2 per bag for curb service. I gave the guy a 20, checked my 2 bags (the F’Lite was 48 pounds and the other was 40), and asked the guy not to bother putting the bags on the scale.
I never leave a bike stock. It’s just in my blood. I’m a mechanical engineer and my job is working primarily on car suspensions. I’m a confessed and unapologetic tinkerer.
My first bit of tinkering happened very early. Right away, I started to try and figure out how to get the bike into the Samsonite case. It’s a little bit of a trick. To get the fork to ‘nest’ in the rear stays, you have to disconnect the shock and rotate the swingarm out of the way. When I did, I couldn’t believe how much force it took to move the swingarm. With no shock, it should freely swing. Well, it doesn’t. So that was the first thing that I started playing with. I pulled the pivot apart and measured it all up. The plastic (nylon?) bush has a little over 1mm of crush on it as delivered. This means there is so much friction, that the spring/shock really never get a chance to operate. No wonder some of the reviews I read stated that the 850# spring seemed too stiff!
Well, I made a spacer to put in the middle of the swing-arm axle. Originally, I took all of the crush off the bushing. That caused some frame stiffness issues (I’ll get into later), so I put some of the crush back in. I’m at about 0.4 mm right now, and it’s a good compromise. The suspension doesn’t feel too stiff at all, and think it could probably use a little more damping.
My first feeling while riding was that the gearing was a little low for me. Sure, if I were actually using this as a mountain bike, then I’d probably need some real spinning gears. That isn’t what I have this bike for, and I really don’t think it’s what anyone has this bike for. So I decided to step up from the stock 46 tooth to a 53t chainring. I like the 53. Another reviewer said that it was a little tall, and he’s probably right. On the open road it’s nice, but to go up a steep hill, you better be prepared to get a little down and dirty. My travels have taken me to Mont Tremblant in Quebec, Canada. It’s a ski village and has some real mountains. My hotel is ½ way up one and getting up that hill is a *****. I doubt if I see any bigger this year. Anyway, I’m using it as a catalyst to get in better shape. If I ride it enough, it won’t feel tall. Pedaling around town, I use 5-6-7th gear, which is right in the middle of the range and it feels nice. Also, be sure to set your derailleur tension and limiters, they come backed out all the way.
The first chainring I bought was for the stock crankset. In higher gears, all I had to do was put 10% of pressure on the pedal, and it would throw the chain off the pedal side of the chainring. I noticed the chain was actually a 7/8 speed chain, so I changed to a 9 speed chain and made it extra long to account for the added teeth on the chainring. That didn’t really help. After looking closer I then noticed some pretty major deflections out of the stock crankset. Let’s be honest, the stock crankset is crap. Aluminum arms and a stamped steel spider pressed on it not a good way to go. I replaced that with a modest FMF BMX crankset, which took another chainring bolt spacing. No big deal, but it sucked to have to buy the same part twice. While replacing the cranks, I noticed the bottom bracket bearing was way, way too stiff. Someone had that bearing preloaded to beat hell. So I set that up properly. That seems to be a common deal. These bikes are built quickly by people who either don’t really know the right way to do it, are instructed to do it in an improper manner, or just don’t care. The change in crankset made a big difference on throwing the chain. Now I had to be pedaling pretty hard to get it to come off. The deflection of the swingarm pivot was starting to be an issue now, so I stuck some of the preload back in it, and that has (almost) fixed the problem entirely. Now on a ½ hour ride, being very conscious to shift slowly and not do anything to confuse the matter, it will probably throw the chain once. This is more than I like, but I can live with it. I will probably get some sort of chain guide soon.
Observations:
1. The fasteners used on this bike are crap. The headset allen that needs to come out to get the bike in suitcase was stripped when I got it. I don’t know how I’ll get it out. I came up with another way to get it in the case, but coming from the factory that way sucks. Also, the shock mounting bolt stripped on me the second time I was installing it. Keep in mind that I do a fair bit of mechanical work in my professional life. I’m not a rock-ape with a crescent wrench. The fasteners are junk and need to be replaced.
2. If you are asking the plastic bushing in the swingarm to not only control rotational motion, but be a big player in the torsional stiffness of the bike, then it needs to be much bigger in diameter. I have an old Schwinn mountain bike (1998 model) that used something similar. It did to with a large diameter tube and a well supported positioning of the bushing. Ultimately, I believe this should be 2 sealed ball bearings with a crush sleeve between them. The loads that you’re putting into this thing just can’t be efficiently controlled by the present arrangement. At some point I think I’m going to do a redesign.
3. Now that I’ve set up the suspension to actually move, it has the tendency to shift gears due to rear swingarm movement. If you hit a big bump, you’ll likely shift into the next gear. I might be able to play with chain length to get rid of this, but I think it’s the nature of the beast.
4. If you stay in the saddle on level ground, the bike feels pretty good. If you try to stand up and sprint or climb a steep hill, the bike really moves around underneath you. This has to be just a part of being a folding bike, but it’s something that needs to be acknowledged. I’m not very sensitive to this. I’ve never noticed it on any other bike, so it must be pretty pronounced.
5. This bike really shouldn’t really be used off road. The tires are road tires and narrow. This bike is represented as having off-road capabilities, but in reality, stay on tarmac. At one point I road on the shoulder of a road and it was pretty dicey. A proper mountain bike wouldn’t even have cared, but I was actually having to do a little work to keep upright. Off-road isn’t new to me. I live in Southern California which has really great mountain biking and plenty of loose dirt/sand to ride in.
6. The brake and derailleur lines should probably be replaced. They’re not the greatest quality. The housings have a lot of flex.
7. If I would have had a couple of these to ride before ordering them off the web, I think I may very well have ended up with a hardtail frame and an internally geared hub. Maybe my gear spread wouldn’t have been quite as big and my ride would have been a little rougher, but I’d be chasing the shifting around a lot less. That alone would be a big gain. I don’t know what derailleur would be an easy swap as a replacement for what I’ve got, but I’m probably going to buy one. I’m not overly impressed with the JuJu.
8. I paid $309 for my bike. For that kind of money, I think the bike is a good buy. It’s doing everything I ask from it and I’m glad I bought it. Having said that, I’ve also put about $100 into getting it more set up to my liking and I'll be spending more in the future. If I would have bought a $500 bike, I’d expect it to have significantly better components. I’m a little surprised that the new Downtubes are so much more expensive. The only difference I can see in them is the new fork. I think they need to be very careful with the pricing. I can see offering a higher end version with better components throughout, but I think they’re advantage in the market right now is in the ‘bang for the buck’ game. They need to not lose sight of that.
Summary:
In short, I’m happy I bought the bike. It gets me out and riding in places that I just couldn’t have before. The bike has some cheesy components, but they can all be changed. I’d like to see better build quality and quality control in the hardware of the bike. I also think that the rear suspension / swing-arm could use a significant re-design. The full-suspension is an interesting choice to have, but, ultimately, I think getting a hardtail is probably a better choice for most users. Looking at the bike as a whole, I think I’ll give it a 8/10 rating. It’s a good choice, but not an absolute slam-dunk. If you ride it very much at all, you’ll probably be doing a number of upgrades.
From the time I opened the box to actually riding the bike was probably less than 15 minutes, and I even read some of the directions! I think the bike looks pretty cool and I was happy with the initial overall looks and finish. The riding position is much better that I expected it to be. The bike is well balanced and handles nicely. The 20” wheels are plenty big enough to be stable. Maybe I could have gotten away with the 16” bike, I don’t know. I did travel on United with the bike in my new Samsonite F’Lite 31 case. I checked it at the curb in Los Angeles. It cost $2 per bag for curb service. I gave the guy a 20, checked my 2 bags (the F’Lite was 48 pounds and the other was 40), and asked the guy not to bother putting the bags on the scale.
I never leave a bike stock. It’s just in my blood. I’m a mechanical engineer and my job is working primarily on car suspensions. I’m a confessed and unapologetic tinkerer.
My first bit of tinkering happened very early. Right away, I started to try and figure out how to get the bike into the Samsonite case. It’s a little bit of a trick. To get the fork to ‘nest’ in the rear stays, you have to disconnect the shock and rotate the swingarm out of the way. When I did, I couldn’t believe how much force it took to move the swingarm. With no shock, it should freely swing. Well, it doesn’t. So that was the first thing that I started playing with. I pulled the pivot apart and measured it all up. The plastic (nylon?) bush has a little over 1mm of crush on it as delivered. This means there is so much friction, that the spring/shock really never get a chance to operate. No wonder some of the reviews I read stated that the 850# spring seemed too stiff!
Well, I made a spacer to put in the middle of the swing-arm axle. Originally, I took all of the crush off the bushing. That caused some frame stiffness issues (I’ll get into later), so I put some of the crush back in. I’m at about 0.4 mm right now, and it’s a good compromise. The suspension doesn’t feel too stiff at all, and think it could probably use a little more damping.
My first feeling while riding was that the gearing was a little low for me. Sure, if I were actually using this as a mountain bike, then I’d probably need some real spinning gears. That isn’t what I have this bike for, and I really don’t think it’s what anyone has this bike for. So I decided to step up from the stock 46 tooth to a 53t chainring. I like the 53. Another reviewer said that it was a little tall, and he’s probably right. On the open road it’s nice, but to go up a steep hill, you better be prepared to get a little down and dirty. My travels have taken me to Mont Tremblant in Quebec, Canada. It’s a ski village and has some real mountains. My hotel is ½ way up one and getting up that hill is a *****. I doubt if I see any bigger this year. Anyway, I’m using it as a catalyst to get in better shape. If I ride it enough, it won’t feel tall. Pedaling around town, I use 5-6-7th gear, which is right in the middle of the range and it feels nice. Also, be sure to set your derailleur tension and limiters, they come backed out all the way.
The first chainring I bought was for the stock crankset. In higher gears, all I had to do was put 10% of pressure on the pedal, and it would throw the chain off the pedal side of the chainring. I noticed the chain was actually a 7/8 speed chain, so I changed to a 9 speed chain and made it extra long to account for the added teeth on the chainring. That didn’t really help. After looking closer I then noticed some pretty major deflections out of the stock crankset. Let’s be honest, the stock crankset is crap. Aluminum arms and a stamped steel spider pressed on it not a good way to go. I replaced that with a modest FMF BMX crankset, which took another chainring bolt spacing. No big deal, but it sucked to have to buy the same part twice. While replacing the cranks, I noticed the bottom bracket bearing was way, way too stiff. Someone had that bearing preloaded to beat hell. So I set that up properly. That seems to be a common deal. These bikes are built quickly by people who either don’t really know the right way to do it, are instructed to do it in an improper manner, or just don’t care. The change in crankset made a big difference on throwing the chain. Now I had to be pedaling pretty hard to get it to come off. The deflection of the swingarm pivot was starting to be an issue now, so I stuck some of the preload back in it, and that has (almost) fixed the problem entirely. Now on a ½ hour ride, being very conscious to shift slowly and not do anything to confuse the matter, it will probably throw the chain once. This is more than I like, but I can live with it. I will probably get some sort of chain guide soon.
Observations:
1. The fasteners used on this bike are crap. The headset allen that needs to come out to get the bike in suitcase was stripped when I got it. I don’t know how I’ll get it out. I came up with another way to get it in the case, but coming from the factory that way sucks. Also, the shock mounting bolt stripped on me the second time I was installing it. Keep in mind that I do a fair bit of mechanical work in my professional life. I’m not a rock-ape with a crescent wrench. The fasteners are junk and need to be replaced.
2. If you are asking the plastic bushing in the swingarm to not only control rotational motion, but be a big player in the torsional stiffness of the bike, then it needs to be much bigger in diameter. I have an old Schwinn mountain bike (1998 model) that used something similar. It did to with a large diameter tube and a well supported positioning of the bushing. Ultimately, I believe this should be 2 sealed ball bearings with a crush sleeve between them. The loads that you’re putting into this thing just can’t be efficiently controlled by the present arrangement. At some point I think I’m going to do a redesign.
3. Now that I’ve set up the suspension to actually move, it has the tendency to shift gears due to rear swingarm movement. If you hit a big bump, you’ll likely shift into the next gear. I might be able to play with chain length to get rid of this, but I think it’s the nature of the beast.
4. If you stay in the saddle on level ground, the bike feels pretty good. If you try to stand up and sprint or climb a steep hill, the bike really moves around underneath you. This has to be just a part of being a folding bike, but it’s something that needs to be acknowledged. I’m not very sensitive to this. I’ve never noticed it on any other bike, so it must be pretty pronounced.
5. This bike really shouldn’t really be used off road. The tires are road tires and narrow. This bike is represented as having off-road capabilities, but in reality, stay on tarmac. At one point I road on the shoulder of a road and it was pretty dicey. A proper mountain bike wouldn’t even have cared, but I was actually having to do a little work to keep upright. Off-road isn’t new to me. I live in Southern California which has really great mountain biking and plenty of loose dirt/sand to ride in.
6. The brake and derailleur lines should probably be replaced. They’re not the greatest quality. The housings have a lot of flex.
7. If I would have had a couple of these to ride before ordering them off the web, I think I may very well have ended up with a hardtail frame and an internally geared hub. Maybe my gear spread wouldn’t have been quite as big and my ride would have been a little rougher, but I’d be chasing the shifting around a lot less. That alone would be a big gain. I don’t know what derailleur would be an easy swap as a replacement for what I’ve got, but I’m probably going to buy one. I’m not overly impressed with the JuJu.
8. I paid $309 for my bike. For that kind of money, I think the bike is a good buy. It’s doing everything I ask from it and I’m glad I bought it. Having said that, I’ve also put about $100 into getting it more set up to my liking and I'll be spending more in the future. If I would have bought a $500 bike, I’d expect it to have significantly better components. I’m a little surprised that the new Downtubes are so much more expensive. The only difference I can see in them is the new fork. I think they need to be very careful with the pricing. I can see offering a higher end version with better components throughout, but I think they’re advantage in the market right now is in the ‘bang for the buck’ game. They need to not lose sight of that.
Summary:
In short, I’m happy I bought the bike. It gets me out and riding in places that I just couldn’t have before. The bike has some cheesy components, but they can all be changed. I’d like to see better build quality and quality control in the hardware of the bike. I also think that the rear suspension / swing-arm could use a significant re-design. The full-suspension is an interesting choice to have, but, ultimately, I think getting a hardtail is probably a better choice for most users. Looking at the bike as a whole, I think I’ll give it a 8/10 rating. It’s a good choice, but not an absolute slam-dunk. If you ride it very much at all, you’ll probably be doing a number of upgrades.