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Help me decide: Tyrell IVE sport vs Birdy vs Tern P10

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Help me decide: Tyrell IVE sport vs Birdy vs Tern P10

Old 06-15-20, 07:00 PM
  #26  
Vinz1590
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Originally Posted by jonmanjiro
Not that I know of. As an owner of a Verge X11, I have been paying very close attention to this, and I have not seen any failures reported for a bike in the latest Verge 451 line up.

AFAIK all the newly reported frame failures after the recalls (which were before the 451 line up was released) have been on bikes with electric motors.

Edit: If you're based in Tokyo, you should get yourself to several shops and view these bikes in person. If the shop doesn't have any test bikes, they will still let you sit on the bikes to see how they feel. I found that both the Tyrell and Birdy folds, while reasonably compact, are quite messy (wheels aren't aligned and point off at an angle). Doesn't look like you can roll the bikes in the folded state. The Tern fold is bulkier, but its also designed so that the bike rolls easily in the folded state (with the handelbars up). So horses for courses. You have to figure out what works for you. Also, since you're in Japan, here's another suggestion for you. The Iruka bike, only available in Japan.
jonmanjiro
I hope that Tern learned from their previous bike recall experience and enhance their QC. It is very frustrating to always worry about the integrity of your bike specially when going high speed on the road. As for the Iruka, it is a wonderful bike that I think can challenge the brompton in term of compact fold. This is a runner up for me but I did not include it to the list because it is fairly new in the market and the luggage option is very limited. I don't know also the upgradability options for this bike.

It seems that you are also located here in Japan? Where did you buy your X11 and what is the cost? I am searching online for a P10 but it is always out of stock. Thanks!
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Old 06-15-20, 09:48 PM
  #27  
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Originally Posted by Vinz1590
jonmanjiro
I hope that Tern learned from their previous bike recall experience and enhance their QC. It is very frustrating to always worry about the integrity of your bike specially when going high speed on the road. As for the Iruka, it is a wonderful bike that I think can challenge the brompton in term of compact fold. This is a runner up for me but I did not include it to the list because it is fairly new in the market and the luggage option is very limited. I don't know also the upgradability options for this bike.

It seems that you are also located here in Japan? Where did you buy your X11 and what is the cost? I am searching online for a P10 but it is always out of stock. Thanks!
Yes, I'm located in Japan. My X11, which I purchased almost two years ago for 190,000 yen? (I don't remember the exact figure) from Best Sport's rakuten store, has a 10 year warranty on the frame, and I check and maintain the bike regularly. Zero problems so far and I'm confident riding the bike like I would any other bike. I couldn't find a P10 for sale online either (though I didn't do that much searching). I suspect there isn't much stock around because more people are buying bikes due to COVID-19.

https://bestsports.jp/
https://www.rakuten.co.jp/auc-bestsports/
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Old 06-15-20, 10:22 PM
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Originally Posted by jonmanjiro
Yes, I'm located in Japan. My X11, which I purchased almost two years ago for 190,000 yen?
Sweeeeeeeeet deal! Currently the X11 is priced at around 270,000+ yen. I will keep searching since I am still waiting for the 100k cash assistance for additional fund. Thanks for the store recommendation!
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Old 06-16-20, 03:16 AM
  #29  
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Originally Posted by Vinz1590
Jipe
Nice mod! Unfortunately, I don't know if this is feasible on an aluminum frame. Maybe if I will choose the birdy, I am just stuck with the rear rack and a klickfix luggage truss that attaches to the seat post. I am not a fan of the pannier bags front rack of the birdy, but hey I can use it as a handle while rolling the bike hehe. Very expensive handle.
For safety of the mod, I reinforced the inner side of the head tube with a piece of titanium tube with about the same diameter of the inner of the head tube bought on eBay and cut in two halves.

But I do not think that it was necessary because the Ti Birdy head tube wall is very thick.

Actually, I do not think its made from a tube but more probably machined to include the semi-integrated headset.

Since the aluminum Birdy also use a semi-integrated headset, its head tube is also probably quite thick and strong enough for a front block.

For the IVE: Boxbike that sells the IVE in Germany claims that its possible to mount 50mm Big Apple tires on the IVE.

Last edited by Jipe; 06-16-20 at 03:20 AM.
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Old 06-17-20, 01:06 AM
  #30  
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I have a Tern Verge D9 with 451 tires and a modified standard Birdy monocoque disc brakes with a MTB 10 speed. The Tern rides well on paved roads but is squirrely on anything less than a decent paved road. Because of the recall issues, I check my hinge regularly but I don't really have peace of mind when I ride the bike. If I had known about the recall issues before I purchased my Tern or my wife's, I would not have done so.
Eventually if I save enough and happen to be passing through Asia, I intent to try to get a Birdy R20 if I can find a good deal or a good used version to replace the Tern. As for the Birdy, it has Jack Black tires, so it's a really stable ride and you can take it on almost any surface. It's a decent gravel grinder. The design of the frame gives me a lot of confidence but it's mainly used by my son, so that's why I want a R 20 for myself. I need to find a good replacement for my wife too.

If you head on over to the Global Birdy Community on Facebook, you'll see photos of modifications people have had done to their Birdys to mount various front mounts. Also some photos of people carrying various large and odd shape cargo on their Birdys

Another good bike to consider is the Downtube 9FS. I had considered it at one point, it's a good deal and you get a lot of bike for the price.
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Old 07-20-20, 02:49 AM
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Hello all! Thank you so much for the replies in this thread. I decided to buy the Tern P10 and it just arrived yesterday. I instantly fell in love with this beautiful bike.My plan next is to maybe upgrade it to have a front derailleur to make it a 3x10 speed drive. Any suggestion on the compatible parts? My idea is to use the Shimano Deore T6000 series (FD, Crank set, and shifter) but I don't know if this is compatible with the existing vanilla components of P10.

Thanks!
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Old 07-20-20, 03:26 AM
  #32  
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Congrats! The P10 is a nice ride. Had the bike a day and already thinking about upgrading?

Hehe, I know the temptation to upgrade is reaaaaaaaally strong and I'm totally guilty myself, because lets face it... its fun! But seriously, those vanilla components, while not as sexy as some options, do work just fine, and the standard rear 11-40T cassette gives the bike a really wide 364% gear range (for a single chainring) already.

If you really do want to add an FD, you will also need to match the capacity of the RD with the FD and new front chainrings, and also change the cassette to make the most of the new gearing i.e. you will most likely need to swap out your entire drive system.

For that reason, I strongly suggest you ride the bike as is for a while and see how you go. More likely than not, you will find the gear range perfectly adequate.

Last edited by Kabuto; 07-20-20 at 03:32 AM.
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Old 07-20-20, 05:23 AM
  #33  
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Originally Posted by jonmanjiro
Congrats! The P10 is a nice ride. Had the bike a day and already thinking about upgrading?

Hehe, I know the temptation to upgrade is reaaaaaaaally strong and I'm totally guilty myself, because lets face it... its fun! But seriously, those vanilla components, while not as sexy as some options, do work just fine, and the standard rear 11-40T cassette gives the bike a really wide 364% gear range (for a single chainring) already.

If you really do want to add an FD, you will also need to match the capacity of the RD with the FD and new front chainrings, and also change the cassette to make the most of the new gearing i.e. you will most likely need to swap out your entire drive system.

For that reason, I strongly suggest you ride the bike as is for a while and see how you go. More likely than not, you will find the gear range perfectly adequate.
Thanks for your advice! And yes, my itch to upgrade is very strong haha. I am just thinking on how I can upgrade into a 3x10 system while utilizing all of its standard components, but I guess it is not that simple.
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Old 07-20-20, 06:06 AM
  #34  
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Originally Posted by Vinz1590
Thanks for your advice! And yes, my itch to upgrade is very strong haha. I am just thinking on how I can upgrade into a 3x10 system while utilizing all of its standard components, but I guess it is not that simple.
Out of curiosity, I did a bit of googling. 3x10 isn't possible, but 2x10 might be with your current RD and cassette. Here's how that would work out.
Assuming your bike has a RD-M610-SGS long cage rear derailleur, your RD capacity is 43T. Your 11-40T cassette is using 29T, which leaves you with a remaining 14T. So you could theoretically install an FD and double front chainring with a difference of 14T. Lets say you keep the 53T chainring you already have and add a 39T chainring. That would give you the following gears. As you can see, the top 7 gears with the 39T chainring overlap gears already available with the 53T chainring, so you really only get two to three new gears at the bottom of the gear range. Great if you want to climb mountains fully loaded, but unnecessary otherwise.

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Old 07-21-20, 07:04 AM
  #35  
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Originally Posted by jonmanjiro
Out of curiosity, I did a bit of googling. 3x10 isn't possible, but 2x10 might be with your current RD and cassette. Here's how that would work out.
Assuming your bike has a RD-M610-SGS long cage rear derailleur, your RD capacity is 43T. Your 11-40T cassette is using 29T, which leaves you with a remaining 14T. So you could theoretically install an FD and double front chainring with a difference of 14T. Lets say you keep the 53T chainring you already have and add a 39T chainring. That would give you the following gears. As you can see, the top 7 gears with the 39T chainring overlap gears already available with the 53T chainring, so you really only get two to three new gears at the bottom of the gear range. Great if you want to climb mountains fully loaded, but unnecessary otherwise.

Thanks for the info @jonmanjiro! I think 2x10 setup is enough. Can you recommend also available parts in the market for this kind of upgrade? I also checked the RD and this P10 2020 model has an RD-M6000-GS only and the cassette is a sunrace 11-40T.

Last edited by Vinz1590; 07-21-20 at 07:12 AM.
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Old 07-21-20, 07:59 AM
  #36  
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Originally Posted by Vinz1590
this P10 2020 model has an RD-M6000-GS only
That's a nice RD, but unfortunately it does *not* have the capacity to support the 2x10 option I mentioned above. So to do a 2x10 setup you would need to change your RD (and the Sunrace cassette too, ideally).

So, back to the drawing board... the 26.4 gear inches you already have with your lowest gear now is actually a very low gear. I suggest you ride your bike for a while and see if you really do need gearing that goes lower first. Chances are you won't.
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Old 07-21-20, 11:30 AM
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Originally Posted by Vinz1590
Hello all! Thank you so much for the replies in this thread. I decided to buy the Tern P10 and it just arrived yesterday. I instantly fell in love with this beautiful bike.My plan next is to maybe upgrade it to have a front derailleur to make it a 3x10 speed drive. Any suggestion on the compatible parts? My idea is to use the Shimano Deore T6000 series (FD, Crank set, and shifter) but I don't know if this is compatible with the existing vanilla components of P10.

Thanks!
wow, what a pity fo choose for tern.
be aware about frame failure, cracks must be inspected in everyride.
hope you be ok.
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Old 07-21-20, 06:20 PM
  #38  
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Originally Posted by jonmanjiro
That's a nice RD, but unfortunately it does *not* have the capacity to support the 2x10 option I mentioned above. So to do a 2x10 setup you would need to change your RD (and the Sunrace cassette too, ideally).

So, back to the drawing board... the 26.4 gear inches you already have with your lowest gear now is actually a very low gear. I suggest you ride your bike for a while and see if you really do need gearing that goes lower first. Chances are you won't.
Oh, what a bummer, but thank you again for sharing your thoughts and yes I will ride it first and see if this is enough. I think you know how steep some areas here in Japan can be hehehe
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Old 07-21-20, 06:27 PM
  #39  
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Originally Posted by BromptonINrio
wow, what a pity fo choose for tern.
be aware about frame failure, cracks must be inspected in everyride.
hope you be ok.
Yes, I hope this will not break on me. I sense a lot of hate for Tern in this forum but i don't usually generalize the frame failure to all models. I hope also that they learnt from their mistakes before and improved their quality control.

Last edited by Vinz1590; 07-21-20 at 07:10 PM.
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Old 07-21-20, 07:29 PM
  #40  
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Originally Posted by Vinz1590
I sense a lot of hate for Tern in this forum
You're not alone there...

FWIW my 2018 model Tern X11 is still going strong and I've ridden many trouble free kilometres on it in recent months (despite all the rain lately).


Also, I have yet to hear of a frame failure for a frame made in Vietnam.
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Old 07-21-20, 07:54 PM
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Originally Posted by Vinz1590
Yes, I hope this will not break on me. I sense a lot of hate for Tern in this forum but i don't usually generalize the frame failure to all models. I hope also that they learnt from their mistakes before and improved their quality control.
dont get me wrong.
i dont work for bike company, so i didnt get a penny to talk good or bad for any brand.
tern is just the worst in quality control, sorry to say.
many frame snnaped in half and many almost fatal crash witth riders all around.

some may say it happens to all brands, even specilized fails...but the question is the is no learning from accidents with terns, and no improve over the years.

with all my hearth i suggest you return your tern for whatever reason and get a birdy, a tyrell, a brompton or any other quality brand.
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Old 07-24-20, 11:53 AM
  #42  
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Originally Posted by jonmanjiro
You're not alone there...

FWIW my 2018 model Tern X11 is still going strong and I've ridden many trouble free kilometres on it in recent months (despite all the rain lately).
Also, I have yet to hear of a frame failure for a frame made in Vietnam.
I, too, sense the hate. The frame failures were a huge black eye for the company, especially so early in their history with a long-term reputation not yet established. The frame hinge/latch design has been changed in at least two important ways, and I am confident that eventually the company's reputation will recover. In my eyes it already has.

My Verge S11i had about 4,000 miles on it when the frame was recalled. I was a bit reluctant to go through the hassle because my frame showed no signs of a developing crack. But I did, and the new frame now has about 4,000 miles on it with no apparent issues.

As the time period that included most of the failures is now several years in the past, I had hoped to see a little less Tern bashing here. Yes, there have been some more recent reports of the same problem, but most of those I've seen have been bikes passed through multiple owners and missed in the recall, or frames converted to e-bikes and possibly overloaded.

One of the most-emphasized parameters in the folding-bike world is light weight. It's a fine line to walk between the lightest weight and the greatest reliability, and all folding bike manufacturers try to stay just over the line on the reliability side. Sometimes design errors or manufacturing defects move that line. On the Consumer Product Safety Commission web site, there are numerous brands listed under "Bicycle Frame Recalls", including Origin8, Fuji, Felt, Marin, Surly, Salsa and Giant. It's not just Tern.

Before our Brompton-loving Tern critic jumps down my throat, Google "Brompton Frame Failures".
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Old 07-24-20, 12:49 PM
  #43  
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Brompton is not the only other possibility, the Tyrell Ive and Birdy have no hinge at all, so no issue with hinge and they fold smaller with an easier to carry package, and there are lightweight models.
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Old 07-25-20, 12:28 AM
  #44  
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The OP has already purchased a Tern P10 and is happy with it. No real need to criticize his choice. Nor would he be able to easily return it. I have both a Birdy and a Tern Verge D9. Both are good bikes with different pros and cons. I have had my Tern for awhile and as I posted above, have had no problems with it. I'm a little nervous about the frame issues, so I check it regularly and it's serial number is not on the recall list. It has been a reliable bike over the years with minimal issues. None really.

I like the Birdy a lot and am dreaming of the R 20 11 spd. The Birdy however is darn difficult to purchase in the US. It's possible but you have to jump through hoops. I wish it was easier and there were more local dealers carrying it and properly servicing it. It would also result in having more used bikes readily available and help keep prices reasonable. As is, people go berserk whenever a decent used version pops up on ebay.
The bike you buy is a personal choice. Our needs can and do change over time, which is why many of us end up with multiple different bikes. Congrats to the OP. I hope you get many years of good riding out of your bike.
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Old 07-25-20, 02:50 AM
  #45  
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Originally Posted by sweeks
I, too, sense the hate. The frame failures were a huge black eye for the company, especially so early in their history with a long-term reputation not yet established. The frame hinge/latch design has been changed in at least two important ways, and I am confident that eventually the company's reputation will recover. In my eyes it already has.

My Verge S11i had about 4,000 miles on it when the frame was recalled. I was a bit reluctant to go through the hassle because my frame showed no signs of a developing crack. But I did, and the new frame now has about 4,000 miles on it with no apparent issues.

As the time period that included most of the failures is now several years in the past, I had hoped to see a little less Tern bashing here. Yes, there have been some more recent reports of the same problem, but most of those I've seen have been bikes passed through multiple owners and missed in the recall, or frames converted to e-bikes and possibly overloaded.

One of the most-emphasized parameters in the folding-bike world is light weight. It's a fine line to walk between the lightest weight and the greatest reliability, and all folding bike manufacturers try to stay just over the line on the reliability side. Sometimes design errors or manufacturing defects move that line. On the Consumer Product Safety Commission web site, there are numerous brands listed under "Bicycle Frame Recalls", including Origin8, Fuji, Felt, Marin, Surly, Salsa and Giant. It's not just Tern.

Before our Brompton-loving Tern critic jumps down my throat, Google "Brompton Frame Failures".

thats a funny search.
bromptom frame failure shows a dahon boardwalk snapped in half, a crashed bromptom with orange frame n and...a tern verge snapped on half!

Congrats!

Last edited by BromptonINrio; 07-25-20 at 02:54 AM.
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Old 07-29-20, 03:41 AM
  #46  
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Is the Rd total chain wrap capacity 41t? You could exceed it as long as you make the chain long enough to get to big-big, and allow the small-small to drag. This means you won't be using the outermost small-small combinations. You can calculate how many gears will drag by comparing the chain wrap capacity to the real wrap. It's ok not to use the outmost combinations since they overlap with some of the big-big.

I have 12-34t 10 speed cassette with 24/44t chainrings. It gives me 519% range with 14-72.6 gear inches on 406x2.1 tires. I mixed my cassette to get 12,13,14,15,17,19,21,24,28,34. This gives me preferred closer stepping at the top and much wider at the bottom. The 20t jump at the front is fine as long as I use a chain catcher. SRAM yaw FD comes with one. The yaw design also makes it so that trim is not necessary but you may need to widen the cage, I had a thread explaining how to do this.
One problem with 20t jump is the chain rub on the outer most 3 gears of small-small against the big chainring but it doesn't matter because I don't use them anyway since the pulley drags due to exceeding the chain wrap capacity of the Rd. I'm using a 4700 GS which has a wrap capacity of 41t. My real wrap is 42t. But my chain length was for 46t chainring instead of the 44t that I have now. So I'm 3t over capacity which means on paper the pulley will drag on the 3 outermost cogs on small-small but it's actually only 2.

I also found the yaw FD to be a couple millimeters closer to the seat tube on my dahon frame then the Shimano 4700 FD which helped a little with chain clearance.
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Old 07-29-20, 03:52 AM
  #47  
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Also the product photos of your specific bike seems to show that it already has a braze on mount for the FD, and if you do have it then you don't need to worry about getting an adapter. However if you do go as small of chainrings as I do, the braze on may not reach low enough. Every 2t difference in the chainring is 8mm of diameter or 4mm of FD height
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Old 07-29-20, 04:16 AM
  #48  
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Originally Posted by tomtomtom123
It gives me 519% range with 14-72.6 gear inches on 406x2.1 tires.
That's seriously low gearing. I'm genuinely curious to know why you require such low gearing? Fully loaded touring up steep mountains???

Originally Posted by tomtomtom123
Also the product photos of your specific bike seems to show that it already has a braze on mount for the FD
It's a chain drop prevention guard thingy. There's no braze-on mount on the P10.
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Old 07-29-20, 04:40 AM
  #49  
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Originally Posted by tomtomtom123
Is the Rd total chain wrap capacity 41t? You could exceed it as long as you make the chain long enough to get to big-big, and allow the small-small to drag. This means you won't be using the outermost small-small combinations. You can calculate how many gears will drag by comparing the chain wrap capacity to the real wrap. It's ok not to use the outmost combinations since they overlap with some of the big-big.

I have 12-34t 10 speed cassette with 24/44t chainrings. It gives me 519% range with 14-72.6 gear inches on 406x2.1 tires. I mixed my cassette to get 12,13,14,15,17,19,21,24,28,34. This gives me preferred closer stepping at the top and much wider at the bottom. The 20t jump at the front is fine as long as I use a chain catcher. SRAM yaw FD comes with one. The yaw design also makes it so that trim is not necessary but you may need to widen the cage, I had a thread explaining how to do this.
Wow!
this gearing is very low!
you probably spin out on flats and spin ou on any incline!
if you find a hill for that low speeds you would probably best pushing the bike, it eill be faster!
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Old 07-29-20, 04:48 AM
  #50  
tomtomtom123
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Most gear range calculators are too high because their tire diameters are oversized. For my 406x2.1 tires, I use 1580mm circumference in my calculations, which is 503mm or 19.8" diameter. I sit on the bike and roll the wheels 2 or 3 revolutions, measure the travel distance, and divide by 2 or 3. This is at a known tire pressure of 2.8-3.0 bar. I tested with 0.5 bar lower and the diameter changed a lot.

14 gear inches is low, but not that low. I've tested it loaded going up various inclines. I cannot remember if it was percentage or degrees of incline, but I remember I could go up to 15-18 degrees or percent while loaded.

During a ride if I encounter a down slope, I only reach 90rpm at 72.6 gear inches for maybe 1 minute per hour. So although I lose some momentum, a higher gear would have only saved me maybe 30 seconds. That's if I encounter the down slope. I prefer to have the lower gear available than having the high gear that I rarely use. Of course, I would prefer 76 or 80 gear inches, and I would get that if I replace the 44t chainring with 46t chainring, and the 22t jump from 24t inner ring actually works on my workstand, but I have never tested the 22t jump on the road and it probably doesn't shift as well. So I leave my setup the way it is. It works for me.

When I did a tour in the past, that bike had I think 18-96 gear inches. 18 gear inches was usually sufficient except on really steep inclines where I would just walk and push. The 96 was rarely used, and the big jumps between 11-13-15t was inconvenient because the comfortable rpm was somewhere in between.

26 gear inches isn't that low. to me. I would go lower.

Normally on flat ground, I am somewhere between 60-68 gear inches at an average of 76rpm which is something like 22-25kph. With some wind resistance I am at 55-60 gear inches or 20-22kph.

Last edited by tomtomtom123; 07-29-20 at 05:11 AM.
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