sjanzeir

Hello everyone,

I was referred over here for possibly more detailed answers. So, what can I possibly do with this?

Thanks in advance.

tudorowen1

This bike has a Sram Neos derailleur and will only work with an 11 to 28 or maybe 30 7 speed rear cassette..So..you need to fit a bigger chainwheel..Probably has a 52 tooth ..could go for a 54 or 56 or even a 60 tooth..Not sure if your chainwheel has detachable chainrings..If it has not you will need to change the cranks and chainring to one where you can change the chainrings..
Make sure your rear cassette has an 11 tooth sprocket..If it has a 12 to 28 cassette changing to an 11 to 28 will make quite a difference..
You can look for an adaptor so the bike can take a normal Shimano derailleur but they are hard to find and it will not change your problems really..unless you could fit a 9 to 26 Capreo hub..but serious money for that..

Rick Imby

The Vybe d7 is probably a Freewheel rear wheel. The smallest high gear you can get on a 7 speed freewheel is probably what comes with the bike.

You could buy a new rear wheel that takes a Cassette but then you would probably want to go to an 8 or 9 or 10 speed cassette and you would need a new shifter also.

Far and away the easiest change is to go to a larger crank but this can be problematic too. If your high gear is a 13 you are going to want to go to a 56-61 chainring if possible. I want at least a 90 gear inch high gear so I do not spin out on smooth flat roads.

Another simple option---Take it back and offer the shop you bought it the difference in price to go to a Speed p8 and an extra $50 for changing your bike to a Used bike.

The 8 speed Dahons all come with an 11 tooth small cog and a chainring big enough to get to 90 gear inches.

Good luck

sjanzeir

Thanks Rick. I already have a Speed D8 along with this Vybe, so I got the speed side covered. I doubt that the shop's return policy would allow any returns/exchanges; it's been a couple of months after all!

That said, I get regular updates on their inventory, and even if they would let me trade in the Vybe, with the possible exception of one or two single-gear Mu's that may or may not pique my interest, there's nothing in their inventory that I like/can afford at this time. But then again, with its lack of high-gear speed, I am treating the Vybe as a single-speed anyway; most of the time, I just set-and-forget seventh gear and call it a day's ride. But even my cheap Chinese Feida (36-12 single-speed; 20x1-3/8 - 37-451 tires) feels a little more efficient to tool around on.

Which is why a slightly faster top three or four cogs would make this D7 a much more usable go-places bike for me. Given the condition of the infrastructure in this city, the balloonish 20x2.10 tires feel much more rugged than the ones on any of my other bikes (except the Shift 2, which I had sold off earlier.) The guys in the other thread directed me towards this faster DNP Epoch 28-11 seven-cog freewheel, which should make for a perfect solution. As a matter of fact, if I do this mod and add a cargo rack, I'd probably end up with my perfect daily rider!

snafu22

Well, the Vybe and the Speed D8 are close cousins, in that both have the original Speed D7 'shopper' as their DNA source. So Vybe is a town/comfort bike in Dahon's lexicon.

Having fiddled around with gearing on the Speed D7 years ago, if you want more 'go' then you're in for the crankset and new 11T on the rear approach.

Rick Imby

Yes that 7 speed 11-28 Freewheel is a solution. I have never seen one of them as Shimano does not make a freewheel with that small of a high gear. There is very little room between the mounting hole and the inside diameter of the gear.

I can understand why they say you need a Deep cassette tool to remove it. That definitely is the easiest route to go to get higher gearing.

I can also understand why it might be less durable than the Shimano freewheels.

sjanzeir

I'm trying not to feel too alarmed by this!

For what it's worth, though, as you can see in the picture I posted in the other thread, the OEM freewheel that's on the bike now is also an Epoch, so I probably shouldn't be too worried about the replacement holding up well enough. Would you agree?

ThorUSA

The Vybe is a good bike for the money, but it is geared pretty low. No problem for most.


The rear is a 14-32 Screw on type sprocket. The front is a 46 teeth. The front is alloy cranks with fixed steel chainring and double chainguard.


If you would change to 53 in the front the top gear would go up from 66 to 75, alternatively ramp up to 56 in front and you would get 79


New crankset and longer chain, plus installation would cost you about 150 dlr if you choose a good crankset.... etc etc...


No dealer can take back a used bike for 50 dlr ... Dealers usually can sell used bikes for around 50 % off new price. Maybe a little more. But that's SELLING price not buying ... Maybe just maybe if the bike is 100 % and could sell as "almost" new, and if you upgrade to a more expensive bike than you could expect maybe 300 dlr credit... Maybe

zoom26

I have a Dahon Vybe D7 as well and a Dahon Speed P8, I upgraded the Speed P8's crankset to a double setup 53/39t then took the FSA 53t and put it on the Vybe D7. As for the freewheel, it is very hard to look for one that has a 11 or at least 12t and a high of either 30,32 or 34. That being said, my Vybe after replacing the freewheel(which I wore out because of bad shifting and winter salt,snow and grime) is geared at a 53t FSA Squared Taper Crankset and a Sunrace 14-28 7spd freewheel which is pretty nice except that I spin out on hills. The Kenda Kwest, though not my favorite, feels a lot lighter than the Speed P8's stock Schwalbe Big Apples (20x1.5 vs 20x1.95). So ultimately, a larger crankset (at least 53t) and a new chain would be the easiest and cheapest upgrade if you want more speed for your Vybe.

sjanzeir

Oops, too late - I already ordered the Epoch 28-11! I'll see how well that works out. That aside, I really like the Vybe - it's rugged, tossable fun. It has that "high-riding BMX" feel to it that I like.

Rick Imby

The 11/28 freewheel from epoch will have a bit more stress on it than the 13/28 because the metal is so thin on the 11 tooth cog.

I did not realize the Vybe had such a small chainring too. Buying another crank for your p8 and passing the p8 crank down seems like another good step.

I really like the 52-11 high gear on a bike with 406 tires, especially if they are not super light/fast tires.

sjanzeir

Could work, but now that I've gone ahead and ordered the 28-11 freewheel, we'll have to wait and see how that works out. It's probably going to take at least a couple of weeks to get here; the Amazon seller does not ship those particular items directly to Saudi Arabia, so I'm having to use a third-party service with a US shipping address, out of which the service will then ship over to me.

sjanzeir

Just got the Park Tool... tool for undoing the OE freewheel this morning; worked as advertized. Now I'm just waiting for the new freewheel to be delivered, which is any day now.

That said, I suspect that this could work as a next step:

52T Aluminum Chainring Crankset with 170mm Arms with Chainguard Black for Folding Bicycles

There's also this...

Lasco 52T Forged Crankset with 170mm Forged Arms CNC Aluminum Chaingard for Folding Bicycles

... But I feel that the latter is just too pricy, even if it makes for easier chainring swapping.

What do you guys think?

Rick Imby

I would go with a 56 or larger sprocket even up to a 61 if I could. That way if you have a problem with the new freewheel your gearing will be ok if you go back to the old freewheel. Having a little higher gear with your new freewheel would not be an issue either.---Personally I want at least a 92 gear inch high gear for fast cruising on flat pavement.

sjanzeir

Okay, got the new DNP freewheel and key, so, out with the old...



... and in with the new:



Then I made a couple of minor adjustments to the derailleur and took it for a ride. While the new cogs gave it a good turn of speed that made it a much more usable bike, I still managed to run out of cadence in seventh gear (albeit far less frequently than with the OE freewheel.) So, yeah, the case for a bigger chainring now looks a lot more compelling, so that's definitely coming next.

Here's the thing, though: I used the Park Took key to undo the OE freewheel; no problems there. But before I spun on the new freewheel, it occurred to me to try the DNP key on both freewheels for fit. While the PT key slipped right in on both, the DNP key fit much more snugly; I had to drive it in with a hammer - and drive it back out with the PT key and said hammer! Now, I wasn't sure if that was done by design or it's just poor quality control, but then I looked at both keys:





As you can see, the teeth on the DNP key (right) are thicker and appear to be more robust than those of the PT key's, so I'm thinking that while PT designed their key to ensure a more universal fit, DNP intentionally made their to fit their smaller-cogged, tight-fit freewheels more snugly to make sure that they don't break as one attempts to unscrew them. What do you think?

jur

Hmmm that depends on the hardness of freewheels and tools. If the freewheel splines were softish steel then the PT one may wreck the freewheel if it was extremely stuck. I would expect the PT tool to be harder steel and not strip out. I like more snug fitting tools, but quality wins every time. So perhaps the DNP tool is softer steel, requiring more material to make it last a bit.

jur

The 11-28T freewheel is a very usable range, ideal for small-wheelers. Coupled with a 54T (or even up to 60T) chainwheel, the bike becomes quite capable of wide speed range.

sjanzeir

My LASCO 52T chainring just arrived this afternoon









While I swapped it in, I could see that the LASCO is much, much lighter than the stock assembly. Now, I was terrified of the idea that I might need a longer chain, but thankfully, the derailleur seemed to be just fine with the slightly less available slack.

I then took the bike out for a test ride and... holy crap, has this thing become fast! Second gear is now where third used to be, but 5th is now just about fast enough for most of the riding I do on this bike! I pushed it as hard as I could on a couple of stretches in 6th and 7th gear; using the latter became viable only of there's a tail wind and/or if the road were slightly sloping downward (and long enough.)

So, I can tell you now that if this were the only bike that I had (and if I added a rack and a pair of fenders,) I'd be perfectly content with it as my only, go-anywhere, do-anything bike! I've even started to question the merit of keeping the Speed D8 around (but I just love that one far too much to let go of it!)

Finally, I must thank everyone who chimed in, helped out, and offered advice and opinions on this and the other thread. Seriously, thanks, buddies!

kayakindude

Hello,

1st time poster and 1st time folding bike owner. I just got the Vybe (C7A) last week and have taken it on 3 test rides. Really like the bike but ran into the same issue on the high gear. In 7th, I am spinning much faster than my normal cadence and can only manage 11-12 mph on average. I feel like I am missing 2-3 more levels.

I saw the mods that you did and my question is...would switching just the front to a 56t (or your 52t) put me more into the 15-16 mph range? I realize the bike is not a racer but I feel like I am several gears away from topping out.

If I understand the gist of this thread, I would have to add 3-4 chain lengths?

badmother

Sheldon Brown's Bicycle Gear Calculator

kayakindude

Thanks badmother. That helped. If I entered everything right I can swap out just the front crank to a 56t and increase my top gear about 25% from stock. Just confirming going from 46t to 56t at least 3-4 more chain lengths?

sjanzeir

Hello @kayakindude,

Thankfully, at least in my particular case, I did not need to add any more chain "links" (I'm presuming that this is what you've been meaning by "lengths"?) because my rear derailleur had enough slack takeup to handle a 52T chainring:



That said, given the fact that the town I live in is mostly flat, I hardly ever use 1st gear anyway, so the derailleur's slack takeup isn't a real-world issue to me. I can't possibly tell you for sure that you won't run into an issue with slack takeup if you swapped in a 56T, but I'd be wary if you use your lowest gear frequently. This is one reason I took a more incremental approach, first trying out a a faster freewheel and then a moderately larger chainring.

kayakindude

Hello Sjanzeir,

Thanks for the feedback. Now that I think about it I have never used 1st. I go down to 2 just as a starting point but the lowest I have gone while riding up a hill is 3. About 90 percent of riding I am in 7th. I find when I am on a main road with traffic I am pedaling like crazy and feel like I am missing at least 2 gears to move up to. Not well versed in messing with bikes but was thinking crank first because it looks like a pretty simple swap...so for $40-50 the bike would become far more useful. Just figuring the 56t would avoid me having to buy the front and back pieces.

Thanks again for your thread- great information and as a newbie with no access to folders in local shops I never even focused on various model gear ratios.

reppans

The general rule is to adjust chain length by ~half the chainring teeth differential (since the chain only engages half the ring).

zoom26

There are a lot of ways to measure a new chain's length, one of them is to pass the chain to the chain ring and to the smallest cog (not going thru the derailleur) then add two links. I have a Vybe c7a too that I swapped the stock 46t to a 53t but thinking of going back to a 46t since I'm in NY and the Vybe's gonna be my main commuter for work. I think I can go to 15-20mph on the basic 46t but I'll be spinning on the downhills. I wish adding a double crankset was an option to the Vybe but the support on the frame by the seatpost makes it nearly impossible to attach a front derailleur.