Brompton 2-speed shifting question.
#1
Brompton 2-speed shifting question.
I bought my Brompton new in 2014. It is a 6-speed. As well as I can remember, when I first got it, it shifted from the smaller rear sprocket up to the larger by simply on move of the 2-speed shifter. For the longest time, it requires a conscious second push down to start the shift. I asked the dealer about this and he said that was normal. Over time I have had to increase the tension in the cable by moving the ferule to furthest position from the trigger in the shifter mechanism. My question is, is this normal?
#2
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NB: in addition to the dealer there is a Q&A directly available through the Company Website, perhaps you can ask there?
cable operated systems do change as the components settle in , and perhaps get contaminated inside the housing run.
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cable operated systems do change as the components settle in , and perhaps get contaminated inside the housing run.
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#3
1. Clean the gunk off the derailleur: It's a well known issue on the Brompton
2. Get a new cable + housing.
Brompton shifting problems ? Ready-Made
#4
#5
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Try just holding it all the way over until the shift takes. That's how friction shifting works, but you're trying to do it as if it's just a button you push and it does it itself. Nope. You gotta move that derailleur until the chain catches up and moves to the other cog.
#6
Try just holding it all the way over until the shift takes. That's how friction shifting works, but you're trying to do it as if it's just a button you push and it does it itself. Nope. You gotta move that derailleur until the chain catches up and moves to the other cog.
It's been a long time since I friction shifted.
#7
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The spring is biased towards the small cog, i.e., if you disconnected the cable the derailleur would snap to the outer/small-cog position. Combine that with the chain having an easier time falling to a smaller cog than climbing to a big one and, yes, you will get a gravity effect.
#8
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This is not to discount that new cables will help, but you'll end up back to slightly harder shifting again soon enough. That wire gets pulled through a long, convoluted run of housing which gets twisted around a lot if you fold regularly. It's just the nature of the Brommie beast.
#10
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I've a Brompton a couple of years older than yours. It has seen a fair amount of work from daily commutes to cycle tours in Cambodia and Australia, but I've never experienced this.
What is your gear changing method? I have always ignored Brompton's advice and back off pressure when changing the front two gears and back pedai for the hub gears.
What is your gear changing method? I have always ignored Brompton's advice and back off pressure when changing the front two gears and back pedai for the hub gears.
#11
My technique is similar to yours in that I back pedal for the hub gears and back off the pressure for the "derailleur" gears but I do pedal forward lightly to make the the "derailleur" shift. My question just involves having to double press the derailleur. I suppose it would make the shift in one press if I press it all the way down and hold it there until it shifts, as Joe Remi suggests. Is that really the nature of the beast? I don't think I was doing that when I first got the bike.
#12
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You know, I've never really thought about it, but haven't noticed anything other than it is a stiffish movement. Never had to double press the derailleur, though. I'll check when I get back home in a couple of days.
I did have the same thing on my Bianchi, though, and a new cable solved the problem.
I did have the same thing on my Bianchi, though, and a new cable solved the problem.
#13
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Just checked on mine. The derailleur is a smooth as silk and operates first time round. The Hub gears are a little stiffer, but, again, no need for a double press.
I'd check with Brompton, if I were you, their support is pretty good and that doesn't seem to be normal behaviour.
I'd check with Brompton, if I were you, their support is pretty good and that doesn't seem to be normal behaviour.







