Go Back  Bike Forums > Bike Forums > Folding Bikes
Reload this Page >

3 Chainrings on Brompton

Notices
Folding Bikes Discuss the unique features and issues of folding bikes. Also a great place to learn what folding bike will work best for your needs.

3 Chainrings on Brompton

Old 10-14-18, 03:47 PM
  #1  
2_i 
Senior Member
Thread Starter
 
Join Date: Sep 2005
Location: Michigan
Posts: 2,615

Bikes: Trek 730, Bike Friday NWT, Brompton M6R*2, Trek 830, Trek 720, Dahon HAT060, Dahon HT060,...

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 390 Post(s)
Liked 31 Times in 24 Posts
3 Chainrings on Brompton

This is a follow-up to the 2 Chainring thread. During the work there it became apparent that there was still space left on the drive side and one more ring could be principally added. 2 rings worked very well but last month, in a hilly area, I ran out of gears and had to walk up. Given that the next month I am to spend in an area that is even more hilly, I started looking into the third ring option seriously. For exploration I got an IRD Triplizer 34T 110/74 BCD and a 24T 74BCD ring. It turned out that a 116mm BB, shoved to the right gave enough space for shifting on a 50-34-24 crankset. At this point I am using a double braze-on derailleur which gives an iffy indexed shifting - a triple derailleur should come in next week. I switched from a Sunrace friction shifter to indexed. The friction one worked a tad better in the current configuration, but I hope this will get remedied with the anticipated triple derailleur rather than the adapted double. I added an in-line shift cable adjuster from Jagwire, due to the lack of cable adjustment on Sunrace. It looks most of this is going to stay - my lowest Brompton gear is now nearly as low as the one on my main bike . One of the photos compares folded Bromptons with 1 and 3 front rings.











Last edited by 2_i; 10-14-18 at 08:59 PM.
2_i is offline  
Old 10-14-18, 04:11 PM
  #2  
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Posts: 41,369

Bikes: 8

Mentioned: 188 Post(s)
Tagged: 0 Thread(s)
Quoted: 6964 Post(s)
Liked 293 Times in 234 Posts
I have a less Iffy Clamp on Front derailleur mount to sell,
hand fabricated. brazed steel,& powder coated..
fietsbob is offline  
Old 10-14-18, 04:26 PM
  #3  
2_i 
Senior Member
Thread Starter
 
Join Date: Sep 2005
Location: Michigan
Posts: 2,615

Bikes: Trek 730, Bike Friday NWT, Brompton M6R*2, Trek 830, Trek 720, Dahon HAT060, Dahon HT060,...

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 390 Post(s)
Liked 31 Times in 24 Posts
Originally Posted by fietsbob View Post
I have a less Iffy Clamp on Front derailleur mount to sell,
hand fabricated. brazed steel,& powder coated..
Is there a photo of that clamp available somewhere?
2_i is offline  
Old 10-15-18, 06:00 AM
  #4  
tudorowen1
Senior Member
 
Join Date: May 2006
Location: Cleethorpes..the last resort..UK
Posts: 329

Bikes: Brompton S6L ,Bike Friday NWT, Phillips 8 speed folder, Trek 930, Thorn XTC

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 67 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
All well and good fitting 3 rings ..and well done for doing that ..but you must have gear ratios down to about 15 gear inches..Why not get off and walk at that speed..And you must have so many duplicated close ratios I cannot see the point..
However I can see the point with a double on the front..
I have a 39 tooth chainwheel on the front with a normal BWR hub gear..so have a gear range from 26 to 78..Low enough to cope with most hills unless I am touring and high enough to ride at 15 /16 mph..
tudorowen1 is offline  
Old 10-15-18, 07:22 AM
  #5  
2_i 
Senior Member
Thread Starter
 
Join Date: Sep 2005
Location: Michigan
Posts: 2,615

Bikes: Trek 730, Bike Friday NWT, Brompton M6R*2, Trek 830, Trek 720, Dahon HAT060, Dahon HT060,...

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 390 Post(s)
Liked 31 Times in 24 Posts
Originally Posted by tudorowen1 View Post
but you must have gear ratios down to about 15 gear inches..Why not get off and walk at that speed.
I go down to 15 on my main bike and I would go down to 18 on Brompton when I calculated.

Originally Posted by tudorowen1 View Post
And you must have so many duplicated close ratios I cannot see the point.
I do not care about the duplication. I want to have stretches of gears that I move within switching just in the rear - the overlap is part of the game.

Originally Posted by tudorowen1 View Post
I have a 39 tooth chainwheel on the front with a normal BWR hub gear..so have a gear range from 26 to 78..Low enough to cope with most hills unless I am touring and high enough to ride at 15 /16 mph..
This sounds fine. However 'most hills' is relative. I go to an area where you have no flat stretches to speak of. First thing there is that you set the horizontal level in the camera on, because in the camera view you hardly ever see anything horizontal. Of course folders behave poorly on slopes so my gearing might not save me, but I will try. Without sufficiently low gears, though, I anticipate that I would be walking the bike half of the time.
2_i is offline  
Old 10-15-18, 08:07 AM
  #6  
tudorowen1
Senior Member
 
Join Date: May 2006
Location: Cleethorpes..the last resort..UK
Posts: 329

Bikes: Brompton S6L ,Bike Friday NWT, Phillips 8 speed folder, Trek 930, Thorn XTC

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 67 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
I understand the need for seriously low gears when touring....and 15 is very very low...Anyway ..well done again on your engineering skills!

Just as a matter of interest which of your bikes do you like best..With me it is by Bike Friday NWT..
tudorowen1 is offline  
Old 10-15-18, 09:54 AM
  #7  
2_i 
Senior Member
Thread Starter
 
Join Date: Sep 2005
Location: Michigan
Posts: 2,615

Bikes: Trek 730, Bike Friday NWT, Brompton M6R*2, Trek 830, Trek 720, Dahon HAT060, Dahon HT060,...

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 390 Post(s)
Liked 31 Times in 24 Posts
Originally Posted by tudorowen1 View Post
Just as a matter of interest which of your bikes do you like best..With me it is by Bike Friday NWT..
I like NWT and its ride is the most confident from among our folders. I still consider taking NWT instead of Brompton into my hilly area, but I may need to pack and unpack the bike quickly locally and there lies its weakness. Also I am put off a bit by its unfinished, in my perception, design and unfinished workmanship. In Dahons I appreciate that they are sturdy, cute and inexpensive. I admire the design in Brompton and its versatility. It is the easiest bike to take along.

From all the bikes I am most attached to 730 because I ride it the most. Otherwise among our bikes I think there is only one that I have serious reservations about, GT (or maybe Giant?), really klutzy, but useful for visitors. Dahons are klutzy too, but they compensate for that in other ways, so I forgive them

How do you like the Thorn and can you say anything about Phillips?
2_i is offline  
Old 10-15-18, 02:26 PM
  #8  
tudorowen1
Senior Member
 
Join Date: May 2006
Location: Cleethorpes..the last resort..UK
Posts: 329

Bikes: Brompton S6L ,Bike Friday NWT, Phillips 8 speed folder, Trek 930, Thorn XTC

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 67 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
The Thorn XTC was a great bike for touring with ultra low gears..18 inch lowest.However I really kept it as an ornament more than anything..It was built in the UK and it was a beautiful piece of work ..But sadly I sold it a few weeks ago.Also I have a Trek 930 which I have had for years and years and I rode the Trans Am on it.Turned it into a great tourer .I just decided there was no point in having 2 bikes that basically did the same job..The Phillips 8 speed folder is just a rebadged Dahon Boardwalk really with a chromoly frame and 8 speed....about 12 years old..Really don't use it much..
tudorowen1 is offline  
Old 10-15-18, 03:06 PM
  #9  
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Posts: 41,369

Bikes: 8

Mentioned: 188 Post(s)
Tagged: 0 Thread(s)
Quoted: 6964 Post(s)
Liked 293 Times in 234 Posts
Originally Posted by 2_i View Post
Is there a photo of that clamp available somewhere?
on my old mac computer that I cannot get to access and post online...
because I'm old and didn' t get computer tech classes in the 50's
fietsbob is offline  
Old 10-15-18, 06:55 PM
  #10  
2_i 
Senior Member
Thread Starter
 
Join Date: Sep 2005
Location: Michigan
Posts: 2,615

Bikes: Trek 730, Bike Friday NWT, Brompton M6R*2, Trek 830, Trek 720, Dahon HAT060, Dahon HT060,...

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 390 Post(s)
Liked 31 Times in 24 Posts
Originally Posted by fietsbob View Post
on my old mac computer that I cannot get to access and post online...
because I'm old and didn' t get computer tech classes in the 50's
I thought it took a phone for the task - I hope the mac did not choke on the clamp
2_i is offline  
Old 10-16-18, 12:44 PM
  #11  
12boy
Senior Member
 
12boy's Avatar
 
Join Date: Oct 2012
Location: casper wy usa
Posts: 427

Bikes: brompton sl, surly steamroller, fuji track, gary fisher bmx minivelo etc

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 131 Post(s)
Liked 4 Times in 2 Posts
I have a 38/ 58 chain ring setup on my Brompton, greasy finger shift style. With a 12 tooth sprocket I have a nice high of almost 78 gear inches, and with the 38 50.9. I have the chain short enough so there isn't a lot of give on the 58 so it won't be too loose on the 38. This is off a 110 crank set which has a provision for a 74 chain ring for which I have a 22 tooth. How does your setup fare with the chain on the smallest chain ring? Any problems with the chain being too loose for the smallest? At this time I only fold the bike with the chain on the 58, which in itself requires some care. Still, 29 gear inches with the 22 tooth would enable me to climb most anything around here.
12boy is offline  
Old 10-16-18, 01:40 PM
  #12  
2_i 
Senior Member
Thread Starter
 
Join Date: Sep 2005
Location: Michigan
Posts: 2,615

Bikes: Trek 730, Bike Friday NWT, Brompton M6R*2, Trek 830, Trek 720, Dahon HAT060, Dahon HT060,...

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 390 Post(s)
Liked 31 Times in 24 Posts
Originally Posted by 12boy View Post
How does your setup fare with the chain on the smallest chain ring? Any problems with the chain being too loose for the smallest? At this time I only fold the bike with the chain on the 58, which in itself requires some care. Still, 29 gear inches with the 22 tooth would enable me to climb most anything around here.
In the first photo the chain is on the smallest ring and you can see that there is still capacity there to take off slack. However I suspect that there is not enough to cover the 58-22 difference - you would need to reduce your ambitions from one end or both, or go to another tensioner. Regarding the latter, from experience I know that picking up a large slack is v. hard. There are no problems with the chain on the smallest ring when folding - see another photo from above a folded bike where the chain is again on the smallest ring.

If I were to shift by moving the chain by hand, as you, I could bring the crankset closer to the frame. Right now its extension on the drive side is forced by the derailleur of which the cage pushes against the seat stay and the derailleur mount when in the lowest gear position. If I resorted to cutting the derailleur cage I could bring everything closer. By now I already tweaked the cage to accomplish the shift to the smallest ring - as it is a double it did not want quite to do it on its own. I hope that with the forthcoming triple derailleur I will either not need any tweaking or just minimal. I am hesitant to go down to cage cutting and resoldering and especially in absence of spares. All the changes till now are reversible.
2_i is offline  
Old 10-16-18, 06:45 PM
  #13  
12boy
Senior Member
 
12boy's Avatar
 
Join Date: Oct 2012
Location: casper wy usa
Posts: 427

Bikes: brompton sl, surly steamroller, fuji track, gary fisher bmx minivelo etc

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 131 Post(s)
Liked 4 Times in 2 Posts
Yeah, the 22 is just too small and nothing much bigger would clear the rear triangle without a wider BB, which would in turn possibly screw up the chain line. Does anyone know if a regular 1 speed hub can be modded to take 2 sprockets? A 2 speed shifter would add very little weight and a 18 tooth sprocket would get the gears down to about 34 gear inches, good enough for here.
12boy is offline  
Old 10-18-18, 05:31 AM
  #14  
Winfried
Senior Member
 
Winfried's Avatar
 
Join Date: Aug 2011
Location: Paris, France
Posts: 1,808
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 279 Post(s)
Liked 6 Times in 5 Posts
Originally Posted by 2_i View Post
Given that the next month I am to spend in an area that is even more hilly, I started looking into the third ring option seriously. For exploration I got an IRD Triplizer 34T 110/74 BCD and a 24T 74BCD ring. It turned out that a 116mm BB, shoved to the right gave enough space for shifting on a 50-34-24 crankset.
Great work.

In hilly areas while touring, I find 46/34T a bit too high.

Considering the 46/30T double subcompacts are a bit pricey, I was thinking of using a triple for that, and simply replace the outer ring with a protector.

Are there triples that support this?

Thank you.
Winfried is offline  
Old 10-18-18, 10:21 AM
  #15  
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Posts: 41,369

Bikes: 8

Mentioned: 188 Post(s)
Tagged: 0 Thread(s)
Quoted: 6964 Post(s)
Liked 293 Times in 234 Posts
yes
fietsbob is offline  
Old 10-18-18, 10:35 AM
  #16  
berlinonaut
Senior Member
 
Join Date: Mar 2016
Posts: 656
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 313 Post(s)
Liked 8 Times in 7 Posts
Originally Posted by 12boy View Post
Yeah, the 22 is just too small and nothing much bigger would clear the rear triangle without a wider BB, which would in turn possibly screw up the chain line. Does anyone know if a regular 1 speed hub can be modded to take 2 sprockets? A 2 speed shifter would add very little weight and a 18 tooth sprocket would get the gears down to about 34 gear inches, good enough for here.
When talking about the Brompton rear-hub the 1-speed and the 2-speed rear wheels are identical. The only difference is that the 2-speed has two cogs on it (and the shifter/derailleur) whereas the 1-speed has one cog and uses the chain-tensioner of the 3-speed, that is not able to shift.
berlinonaut is offline  
Old 10-18-18, 10:40 AM
  #17  
2_i 
Senior Member
Thread Starter
 
Join Date: Sep 2005
Location: Michigan
Posts: 2,615

Bikes: Trek 730, Bike Friday NWT, Brompton M6R*2, Trek 830, Trek 720, Dahon HAT060, Dahon HT060,...

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 390 Post(s)
Liked 31 Times in 24 Posts
Originally Posted by Winfried View Post
Considering the 46/30T double subcompacts are a bit pricey, I was thinking of using a triple for that, and simply replace the outer ring with a protector.

Are there triples that support this?

Thank you.
I obviously followed your poking around for subcompacts and they are indeed either expensive or not available. As to the triple, a 110/74 crankset should do it and you can find cheap ones on Ebay, including just a right-side crank.

Originally Posted by Winfried View Post
Great work.
Thanks, but actually it is not quite finished. A triple braze-on derailleur came in, a low-end Shimano, and it looks that a derailleur will end-up being a bottle neck in the whole setup. At this point the triple works worse than double, though to give it justice, I tweaked so far the double but not the triple derailleur. In essence triple derailleurs have longer lever arms and sturdier cages. The latter is achieved with thicker steel but also more enhanced 3D structure. That structure pushes the derailleur farther from the seat tube than a double derailleur. In addition, the adapters for mounting the derailleur on Brompton interfere with the beefed up structure, such as catching the cage. It would have been easier if the band of the adapter, circumventing the seat tube, ran above the derailleur mounting point, not below. Putting it below leads to that interference. I am not sure I will solve this before my trip next month. Another derailleur, a better quality Shimano, will come in and I hope that its shape is a tad more disciplined, facilitating tweaking.
2_i is offline  
Old 10-18-18, 11:49 AM
  #18  
Winfried
Senior Member
 
Winfried's Avatar
 
Join Date: Aug 2011
Location: Paris, France
Posts: 1,808
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 279 Post(s)
Liked 6 Times in 5 Posts
Originally Posted by 2_i View Post
I obviously followed your poking around for subcompacts and they are indeed either expensive or not available. As to the triple, a 110/74 crankset should do it and you can find cheap ones on Ebay, including just a right-side crank.
Thanks. I'll see what I can find.

Apparently, with a BWR + 13/16T cassette, a 46/32T would provide a larger number of individual speeds.
Winfried is offline  
Old 10-21-18, 05:44 PM
  #19  
2_i 
Senior Member
Thread Starter
 
Join Date: Sep 2005
Location: Michigan
Posts: 2,615

Bikes: Trek 730, Bike Friday NWT, Brompton M6R*2, Trek 830, Trek 720, Dahon HAT060, Dahon HT060,...

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 390 Post(s)
Liked 31 Times in 24 Posts
Update: I solved the derailleur problem and have a smoothly shifting 50-34-24 triple on Brompton. It is a tad more compact than at the start of the triple project. Some problem with the Litepro mount emerged though, to be looked at further.

Details: After second triple derailleur arrived, it became completely obvious that a triple derailleur is completely out of question on Brompton. Those derailleurs waste so much space that mounting them and making them functional would disable standard Brompton folding. I returned to double derailleur, particularly upon reading the blessing of Jan Heine for the use of double derailleurs with triple cranksets. A double derailleur has enough capacity for 3 rings, but barely, so the problem is fitting the 3 rings within the range and having the middle ring well positioned within the range - the tolerances are very tight. To make a full use of the range of double der, I had to remodel its cage, shortening it so that the cage would not rest on the rear triangle, Further, to enable downshift from middle to small ring, I had to narrow the cage towards its new bottom. The final touch was to bring the small ring closer to middle, by using thinner spacers than normally recommended, this to make upshift from small to middle ring smooth. At this point shifting works like butter. I was able to go back to 114mm BB. The overall weight cost is 73g more than double and 329g more than single.

A problem emerged (or got confirmed) with the Litepro derailleur adapter for Dahon K-frames. In that adapter the derailleur is attached to a thin stub out of alu. When there is a glitch in shifting that stub twists and flexes perpetuating the problem in shifting. @Winfried, you claimed that there is no problem there, but in my experience the problem is pronounced. In fact in my adapter the stub now has a permanent arch while it was straight in the beginning. That arch developed exclusively during testing, when I mostly drove the cranks by hand. Now the shifting is so smooth that there are no glitches but I am dissatisfied with a component that is this marginal and will next try the adapter for P-frames that has a shorter stub for derailleur mounting.

The photos illustrate the progress:









Last edited by 2_i; 10-21-18 at 09:46 PM.
2_i is offline  
Old 10-21-18, 05:50 PM
  #20  
2_i 
Senior Member
Thread Starter
 
Join Date: Sep 2005
Location: Michigan
Posts: 2,615

Bikes: Trek 730, Bike Friday NWT, Brompton M6R*2, Trek 830, Trek 720, Dahon HAT060, Dahon HT060,...

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 390 Post(s)
Liked 31 Times in 24 Posts
P.S. After you attach photos, it becomes impossible to edit given a poor interaction of a browser with the page, so I add the info in a separate message. Cage modification can be done by soldering using a kit for stainless steel such as Stay-Brite and stainless steel pieces.
2_i is offline  
Old 10-22-18, 12:17 PM
  #21  
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Posts: 41,369

Bikes: 8

Mentioned: 188 Post(s)
Tagged: 0 Thread(s)
Quoted: 6964 Post(s)
Liked 293 Times in 234 Posts
here is a Triple internally geared crank Efneo GTRO a 28t physical chainring
attached to the gear box, So, has 2 internal overdrive gears,
as if it has a 40 and 50t chainring,
but the chain is still on the 1 chainring, it turns faster than the crank-arms in 2nd & 3rd..
a lever shifts the gears with a cable , no FD at all ..
For a fast shift at any speed..

fietsbob is offline  
Old 10-22-18, 12:55 PM
  #22  
2_i 
Senior Member
Thread Starter
 
Join Date: Sep 2005
Location: Michigan
Posts: 2,615

Bikes: Trek 730, Bike Friday NWT, Brompton M6R*2, Trek 830, Trek 720, Dahon HAT060, Dahon HT060,...

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 390 Post(s)
Liked 31 Times in 24 Posts
Originally Posted by fietsbob View Post
here is a Triple internally geared crank Efneo GTRO a 28t physical chainring
attached to the gear box, So, has 2 internal overdrive gears,
as if it has a 40 and 50t chainring,
but the chain is still on the 1 chainring, it turns faster than the crank-arms in 2nd & 3rd..
a lever shifts the gears with a cable , no FD at all ..
For a fast shift at any speed..
Thanks, it principally looks good, but then for Brompton they say that it is 37T ring. I am not sure where the latter limitation comes from and without correspondence with them it might be difficult to figure that out. Is it a challenge to BWR and then 24T in triple is bad too?? Fortunately I am on the lower side of Gaussian curve and maybe exert weaker forces. One review says that GTRO's net weight comes up to 1.6kg.
2_i is offline  
Old 10-22-18, 01:18 PM
  #23  
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Posts: 41,369

Bikes: 8

Mentioned: 188 Post(s)
Tagged: 0 Thread(s)
Quoted: 6964 Post(s)
Liked 293 Times in 234 Posts
IDK Just offering a suggestion, (Merry Sales distributes them to shops)

I have had a Schlumpf Mountain drive geared crank * for 10 years , on my 3 speed Brompton,

it, a reduction gear , 54t acts like a 21.6t in low gear and the 3 speeds are run through a 2nd time.
for 6 over a wire range.. a heel button on the crank shift no cable.

* in low range, the crank arms turn 2.5x the chain ring speed, ..
moved it to my M3L after I got it, proven , on my older Mk2,shown, which I then sold. with stock crank..


Last edited by fietsbob; 10-22-18 at 01:25 PM.
fietsbob is offline  
Old 10-24-18, 03:18 PM
  #24  
tomtomtom123
Senior Member
 
Join Date: Jan 2017
Posts: 738
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 229 Post(s)
Likes: 0
Liked 65 Times in 43 Posts
How did you manage to fit the triple derailleur? I tried it on my Dahon, but it didn't fit. I don't remember what the problem was but I think the swing mechanism was thicker or the swing starts further in, causing interference from the seat tube or making the derailleur start further out when compared to the double.

I ended up putting on a double. I also had to bend the plates to get them wider. I used the Litepro P adapter but the bracket was designed poorly and wouldn't fit any of the derailleurs I tried, so I 3D printed my own out of stainless steel bronze, with the clamp mounted from above. I used 2 clamps, one lower with a cable stop. The stainless steel bronze was almost 150-200g, because I made them very thick since the material tends to be brittle. Aluminum is stronger and could be half the thickness at 40-50g, but costs twice as much to print.

I have a 26/46 and I found 20t jump to be the limit, with 8mm chainring spacing. If I spaced it wider, it won't shift. If I space it closer, the chain while on the inner ring will rub on the outer ring when trying to go higher than 6th gear. With 8mm spacing I can run it up to 7th gear. I used 8mm and 10mm DIN 988 shim washers, 0.2mm thickness, to adjust the spacing, you can buy a 100 pack for $3 on ebay. It needed a chain catcher, without one the chain would drop once every couple days.






Last edited by tomtomtom123; 10-24-18 at 03:22 PM.
tomtomtom123 is offline  
Old 10-24-18, 04:03 PM
  #25  
Winfried
Senior Member
 
Winfried's Avatar
 
Join Date: Aug 2011
Location: Paris, France
Posts: 1,808
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 279 Post(s)
Liked 6 Times in 5 Posts
Originally Posted by 2_i View Post
@Winfried, you claimed that there is no problem there, but in my experience the problem is pronounced. In fact in my adapter the stub now has a permanent arch while it was straight in the beginning. That arch developed exclusively during testing, when I mostly drove the cranks by hand. Now the shifting is so smooth that there are no glitches but I am dissatisfied with a component that is this marginal and will next try the adapter for P-frames that has a shorter stub for derailleur mounting.
I've been using a Shimano Triaga derailleur + Stronlight double chainring + Litepro Clamp Adapter for K Series Frame for over two years now, with no problem whatsoever.

Here, apparently, you used a triple chainring and a double derailleur you pushed ot its limits, so it's quite a different setup.
Winfried is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.