Bromptom with dahon andros stem extender advice
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Bromptom with dahon andros stem extender advice
I brought two Dahon/ Tern Anros extenders to go on a Brompton, or maybe a Mezzo.
I would like advice about bars that would fit this mod. I have a bar that I can cut down for use for the mount.
Does anyone know the Diametre bars I need to fit.
I would prefer bullbars like the speed TT.
Will post a picture when I can.
I would like advice about bars that would fit this mod. I have a bar that I can cut down for use for the mount.
Does anyone know the Diametre bars I need to fit.
I would prefer bullbars like the speed TT.
Will post a picture when I can.
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Problems
Pictures shown with normal bars, which are too narrow to fit. Testing with straight bar for extension mount , will cut thess down if i end up using it.
1) need larger diametre bars. Size ?
2) can only have very upright with out modifing stem due to clearence around clamp(pic 2). This results in less forward reach, reason for mod. Might not matter as allow bars with further reach to be fitted and still fold.
3) extra folding stage.
4) Availalbe Dahon stubby bar instead of cutting down bars.
Pictures shown with normal bars, which are too narrow to fit. Testing with straight bar for extension mount , will cut thess down if i end up using it.
1) need larger diametre bars. Size ?
2) can only have very upright with out modifing stem due to clearence around clamp(pic 2). This results in less forward reach, reason for mod. Might not matter as allow bars with further reach to be fitted and still fold.
3) extra folding stage.
4) Availalbe Dahon stubby bar instead of cutting down bars.
Last edited by bhkyte; 11-11-12 at 01:15 PM.
#3
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Oh this is a useful thread; thanks for starting it! My guess is that you need bars that have a wide 25.4mm area, as opposed to just the typical stem portion at the center. A good alternative for fitting bars with smaller dimension is to use foil/ aluminum tape to "shim" the bar and make it a good fit.
What are your impressions of the andros stem so far, in terms of quality build/ safety?
Also, do you think it is possible to fit drop bars or bullhorns in those bars? I ask because you would have to slip it through some of the bars' tight corners.
Keep us updated!
What are your impressions of the andros stem so far, in terms of quality build/ safety?
Also, do you think it is possible to fit drop bars or bullhorns in those bars? I ask because you would have to slip it through some of the bars' tight corners.
Keep us updated!
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Oh this is a useful thread; thanks for starting it!
1)My guess is that you need bars that have a wide 25.4mm area, as opposed to just the typical stem portion at the center. A good alternative for fitting bars with smaller dimension is to use foil/ aluminum tape to "shim" the bar and make it a good fit.
2)What are your impressions of the andros stem so far, in terms of quality build/ safety?
3)Also, do you think it is possible to fit drop bars or bullhorns in those bars? I ask because you would have to slip it through some of the bars' tight corners.
Keep us updated!
1)My guess is that you need bars that have a wide 25.4mm area, as opposed to just the typical stem portion at the center. A good alternative for fitting bars with smaller dimension is to use foil/ aluminum tape to "shim" the bar and make it a good fit.
2)What are your impressions of the andros stem so far, in terms of quality build/ safety?
3)Also, do you think it is possible to fit drop bars or bullhorns in those bars? I ask because you would have to slip it through some of the bars' tight corners.
Keep us updated!
2) Quality looks Ok, but expensive. Worried it might crack, no warranty information.
3) I think drops will fit. The two sections of the andros stem are seperatable, only connected by the top closer/clamp. If you look at the fourth picture you might see what I mean.
So the bars should just slip through either clamp, then connect to the closing mechanism in the middle .
Last edited by bhkyte; 11-17-12 at 03:37 AM.
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these work well:
https://www.ebay.com/itm/2011-GUB-Ste...item51a400c7d6
comes with its own mount. not necessary to cut a bar down. use a quick release on the brompton mast instead of the set screw.
https://www.ebay.com/itm/2011-GUB-Ste...item51a400c7d6
comes with its own mount. not necessary to cut a bar down. use a quick release on the brompton mast instead of the set screw.
#6
Banned
The ones Thor stocks are offset back towards the center, to grip a sleeved bar,
IDK about the center bulge, maybe he will chime in, [I don't own one]
and open faced, so unbolts to suit odd bends..
Modolo Dumbo* is a trekking bar setup, of 3 U shaped pieces and machined clamps ..
very adjustable.. , but a wrench job... on a folder, not so multimode commuter quick..
*SJS had them in stock.
What are you trying to accomplish?
IDK about the center bulge, maybe he will chime in, [I don't own one]
and open faced, so unbolts to suit odd bends..
Modolo Dumbo* is a trekking bar setup, of 3 U shaped pieces and machined clamps ..
very adjustable.. , but a wrench job... on a folder, not so multimode commuter quick..
*SJS had them in stock.
What are you trying to accomplish?
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Sorry whats the advangers of a P or s type stem?
I am looking for several inchs more forward reach, and road bars. Not just a slight alteration in stem angle.
Would one of the differenet brompton stems clear the andros clear the bolt better?
I am looking for several inchs more forward reach, and road bars. Not just a slight alteration in stem angle.
Would one of the differenet brompton stems clear the andros clear the bolt better?
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You'll have to research the geometry to find the best solution (there's a diagram somewhere on the net with precise cockpit measurements for brompton types) but I seem to remember littlepixel's bike started off with S stem and drop bar, before he switched to the moustache and the geometry looked good.
#13
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You'll have to research the geometry to find the best solution (there's a diagram somewhere on the net with precise cockpit measurements for brompton types) but I seem to remember littlepixel's bike started off with S stem and drop bar, before he switched to the moustache and the geometry looked good.
#14
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I had a mk 2 bike the 90's bikes used a seat post binder bolt to clamp the handle bar.
I got mine 3rd hand with a seat post QR. [big bolt type]
if you want the bull horn bar* , it wont fold, without rotating the bars in the steerer mast. [* and, say, reverse brake levers]
2 options to get: something recently offered the H mast, is made with hinge higher,
to not have M bar hit the ground folded but raise bar to 60mm
( use a seat post QR, thin bolt ones , more common now. )
S bar mast is about as tall , with hinge at the bottom,
so with other than a low rise bar
Folding to the latch, the handlebar hits the ground and lower.
You have a long bar-end grip combination with Ergon GR5,
but they need to be rotated , by loosening clamp bolts,
to fold down to the latch [I tried them on my M bars, that worked]
went with shorter bar-end GR3.. no bolt loosening needed
Brakes stay on the M bars in this case.
So I'd say H riser + a QR .. and you may scratch the bars over time
turning them in the clamp frequently ,
So, plan to replace them before they break along those scratch lines.
Want more reach? adding a Saddle Adapter Pin, and so, moving seat back.
[I used one on my Mk2, it is a shorter main frame, than the current ones
I got mine 3rd hand with a seat post QR. [big bolt type]
if you want the bull horn bar* , it wont fold, without rotating the bars in the steerer mast. [* and, say, reverse brake levers]
2 options to get: something recently offered the H mast, is made with hinge higher,
to not have M bar hit the ground folded but raise bar to 60mm
( use a seat post QR, thin bolt ones , more common now. )
S bar mast is about as tall , with hinge at the bottom,
so with other than a low rise bar
Folding to the latch, the handlebar hits the ground and lower.
You have a long bar-end grip combination with Ergon GR5,
but they need to be rotated , by loosening clamp bolts,
to fold down to the latch [I tried them on my M bars, that worked]
went with shorter bar-end GR3.. no bolt loosening needed
Brakes stay on the M bars in this case.
So I'd say H riser + a QR .. and you may scratch the bars over time
turning them in the clamp frequently ,
So, plan to replace them before they break along those scratch lines.
Want more reach? adding a Saddle Adapter Pin, and so, moving seat back.
[I used one on my Mk2, it is a shorter main frame, than the current ones
Last edited by fietsbob; 11-18-12 at 11:37 AM.
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I had a mk 2 bike the 90's bikes used a seat post binder bolt to clamp the handle bar.
I got mine 3rd hand with a seat post QR. [big bolt type]
if you want the bull horn bar* , it wont fold, without rotating the bars in the steerer mast. [* and, say, reverse brake levers]
2 options to get: something recently offered the H mast, is made with hinge higher,
to not have M bar hit the ground folded but raise bar to 60mm
( use a seat post QR, thin bolt ones , more common now. )
S bar mast is about as tall , with hinge at the bottom,
so with other than a low rise bar
Folding to the latch, the handlebar hits the ground and lower.
You have a long bar-end grip combination with Ergon GR5,
but they need to be rotated , by loosening clamp bolts,
to fold down to the latch [I tried them on my M bars, that worked]
went with shorter bar-end GR3.. no bolt loosening needed
Brakes stay on the M bars in this case.
So I'd say H riser + a QR .. and you may scratch the bars over time
turning them in the clamp frequently ,
So, plan to replace them before they break along those scratch lines.
Want more reach? adding a Saddle Adapter Pin, and so, moving seat back.
[I used one on my Mk2, it is a shorter main frame, than the current ones
I got mine 3rd hand with a seat post QR. [big bolt type]
if you want the bull horn bar* , it wont fold, without rotating the bars in the steerer mast. [* and, say, reverse brake levers]
2 options to get: something recently offered the H mast, is made with hinge higher,
to not have M bar hit the ground folded but raise bar to 60mm
( use a seat post QR, thin bolt ones , more common now. )
S bar mast is about as tall , with hinge at the bottom,
so with other than a low rise bar
Folding to the latch, the handlebar hits the ground and lower.
You have a long bar-end grip combination with Ergon GR5,
but they need to be rotated , by loosening clamp bolts,
to fold down to the latch [I tried them on my M bars, that worked]
went with shorter bar-end GR3.. no bolt loosening needed
Brakes stay on the M bars in this case.
So I'd say H riser + a QR .. and you may scratch the bars over time
turning them in the clamp frequently ,
So, plan to replace them before they break along those scratch lines.
Want more reach? adding a Saddle Adapter Pin, and so, moving seat back.
[I used one on my Mk2, it is a shorter main frame, than the current ones
I think I will be ok if I go for shorter bull bars.
I made mine from cut down drops for the mezzo. However they are droped bars turned on to side and then cut down, rather than upside down and cut. They are not as long as Usual CUT down bull bars made from drops.
It still made the fold wider on the mezzo, but I think WITH the andros stem I can get a flat fold on the brommie. Or maybe I could get the mezzo folding a bit flatter if i used the andros ( plus more reach.)
Last edited by bhkyte; 11-18-12 at 04:33 PM.
#16
Banned
I also have a bike friday, they use a split bar center.. 4 pieces..
inner sleeve, 2 bar halves + the outer sleeve,
for width reduction, cut the bulge out, and make the width that much less,
Choose inner sleeve to fit the ID. [1 side bonded into bar half]
outer sleeve is 1" OD/7/8" ID split along the length, and so compressed
to hold the 2 halves ..
together.. by the stem
inner sleeve, 2 bar halves + the outer sleeve,
for width reduction, cut the bulge out, and make the width that much less,
Choose inner sleeve to fit the ID. [1 side bonded into bar half]
outer sleeve is 1" OD/7/8" ID split along the length, and so compressed
to hold the 2 halves ..
together.. by the stem
#17
Part-time epistemologist
You'll have to research the geometry to find the best solution (there's a diagram somewhere on the net with precise cockpit measurements for brompton types) but I seem to remember littlepixel's bike started off with S stem and drop bar, before he switched to the moustache and the geometry looked good.
https://groups.yahoo.com/group/Brompt...61368/pic/list
... of course, there might be another source. But that page is very helpful.
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Folding to the latch, the handlebar hits the ground and lower.
[/QUOTE]
I have 120mm scooter wheels fitted on the rack and 72mm transit wheel rollerblade , this might help with clearence ??
[/QUOTE]
I have 120mm scooter wheels fitted on the rack and 72mm transit wheel rollerblade , this might help with clearence ??
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Latest efforts. Photo shows old drop bars turned upside down, intend to cut down in to bull bars and add road racing levers (plus longer cables). like mezzo pictured Leaving striaght bars on temporally, so bike is still usable for moment.
I am considering just going for a tt bar without the dahon stem.
For the moment I am trying these bars 43cm width , 25.4 stem over around 11 cm clamping area. Around 9cm is need for clamp area. Had difficulty finding a source for these. Any ideas??
Ironically the bars from my Mezzo are wide enough.
I could swop them over. But it along time to get the riding postion and compromise on a compact fold, (+3 inches), on the Mezzo, so I would sooner find some other bars then meddle with it.
Issues
1) If I can find a wider bar , around 2cm minium bigger 45cm plus it will clear either side of the wheel. I might not need the andros stem then ,but might be too low. Change stem to longer as Fietsbob suggest ?? (I dont like paying out proper prices like £120 for new stem!! Mind you the dahon stem was around £55), Other issue with this is its best if the brake levers on bullbars are angled inwards (see picture 7), so do they need to be even wider to accommdate??
2) not sure about brake levers clearence, need to get some to try it out and see about above issue.
3) this is a five speed bike, could I use Brifters ?? ( ten speed two clicks each??) else mount lever on top bar ends ??
Just realise I posted this also in the drop bar bromptom thread all so !!!!!!!!!!!
Oh well..............
I am considering just going for a tt bar without the dahon stem.
For the moment I am trying these bars 43cm width , 25.4 stem over around 11 cm clamping area. Around 9cm is need for clamp area. Had difficulty finding a source for these. Any ideas??
Ironically the bars from my Mezzo are wide enough.
I could swop them over. But it along time to get the riding postion and compromise on a compact fold, (+3 inches), on the Mezzo, so I would sooner find some other bars then meddle with it.
Issues
1) If I can find a wider bar , around 2cm minium bigger 45cm plus it will clear either side of the wheel. I might not need the andros stem then ,but might be too low. Change stem to longer as Fietsbob suggest ?? (I dont like paying out proper prices like £120 for new stem!! Mind you the dahon stem was around £55), Other issue with this is its best if the brake levers on bullbars are angled inwards (see picture 7), so do they need to be even wider to accommdate??
2) not sure about brake levers clearence, need to get some to try it out and see about above issue.
3) this is a five speed bike, could I use Brifters ?? ( ten speed two clicks each??) else mount lever on top bar ends ??
Just realise I posted this also in the drop bar bromptom thread all so !!!!!!!!!!!
Oh well..............
Last edited by bhkyte; 12-05-12 at 01:14 PM.
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Possibly thinking of this with out Dahon stem;
https://www.ebay.co.uk/itm/1210330449...84.m1435.l2649
never occurred to me that Afline 11 speed would work with a 11 speed brifter (brake/gear lever). Just the problem of the rear axle width to fit it and the expense???
With the Dahon Andros stem its looking so good so far. Just need the levers and some longer brake cables. Will post a picture when I get a bit further
https://www.ebay.co.uk/itm/1210330449...84.m1435.l2649
never occurred to me that Afline 11 speed would work with a 11 speed brifter (brake/gear lever). Just the problem of the rear axle width to fit it and the expense???
With the Dahon Andros stem its looking so good so far. Just need the levers and some longer brake cables. Will post a picture when I get a bit further
Last edited by bhkyte; 12-10-12 at 11:53 AM.
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Check out the conversion kit you can buy from Kinetics: https://www.kinetics.org.uk/html/8-speed.html
(However, I don't know enough about road bike stuff to know if there's an 8 speed "brifter" on the market anywhere?)
By the way, I'm loving the idea of the Andros QR stem mod... I would love to do this to my Birdy and also add bull bars (but I doubt I'll ever seriously do it).
#22
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Yes I know about the 8 speed. "Stomatash" a Brompton expert started the awareness of this option about 4 years ago on this site, at least to me.
Can,t see myself spending £300 on a conversion kit, espically when I here problems with it slipping in some gears.
Many people had this problem ??
I know "Jur" and stomatash have reported it.
Can I run a SA8 hub from a brifter??
there are plenty of 8 speed on ebay, ( and a few 7 speeds if I want drops on my sash dual drive on the gold MEzzo)
Maybe there is hope for me to get the bike set up I prefer out of a brompton after all !!!!! ( the dark side is calling , snauf where are you, Actually snafu where are you???? )
Can,t see myself spending £300 on a conversion kit, espically when I here problems with it slipping in some gears.
Many people had this problem ??
I know "Jur" and stomatash have reported it.
Can I run a SA8 hub from a brifter??
there are plenty of 8 speed on ebay, ( and a few 7 speeds if I want drops on my sash dual drive on the gold MEzzo)
Maybe there is hope for me to get the bike set up I prefer out of a brompton after all !!!!! ( the dark side is calling , snauf where are you, Actually snafu where are you???? )
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Dropped bars cut down just need to cut down extender bar and fit road levers and longer cables,
Might go for internals. It will be just as compact folded as standard Bromptom when other handlebars are cut down. The bars will invert fully so that the lever does not protude as it does now (picture 1).
Not sure what do do about gear lever yet for time being.
Might go for internals. It will be just as compact folded as standard Bromptom when other handlebars are cut down. The bars will invert fully so that the lever does not protude as it does now (picture 1).
Not sure what do do about gear lever yet for time being.
Last edited by bhkyte; 12-10-12 at 05:46 PM.
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Ahh.... I've only been on the forums for 2 years, so I wasn't aware of the older threads about the SA 8 speed hub on a Brommie (and I wasn't aware of the issues with them skipping either).
The bars are progressing nicely! Regarding the gear lever, are there any bar end style shifters that might work in your application?
Something like these shifters? (...not my bike mind you.... just a random pic I found)
The bars are progressing nicely! Regarding the gear lever, are there any bar end style shifters that might work in your application?
Something like these shifters? (...not my bike mind you.... just a random pic I found)
#25
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Just that, safety wise,
I would never use Interruptor levers on the end of the cable, there are parts for proper reverse levers,
with the shifters on the sides of them, for the Triathlon racing Bicycles ..
I would never use Interruptor levers on the end of the cable, there are parts for proper reverse levers,
with the shifters on the sides of them, for the Triathlon racing Bicycles ..