Ralph-e (my Alfine 11-speed Brompton – with a GrinTech electric conversion) has had a frustrating “chain drop” issue throughout the 5 years we’ve been together. With “Murphy’s Law” timing, infrequently the chain can be dislodged from the rear cog & chain tensioner sprockets. I’ve developed a second-sense feel for a successful unparking step, although I admit to including a quick look down at the chain at the rear hub before attempting to ride away.
The following 3 pics illustrate the scenario: (1) taut chain over the rear cog, (2) slight reduction of tension in the chain (where the chain is sagging & starting to slide down & out over the widened rear frame), (3) further reduction of tension (resulting in further chain sag over the frame & commencement of the chain moving off the teeth of the cog). At this point, if the rear wheel rotates backwards then the chain will fall off the cog & then off the tensioner sprockets. The reduction in chain tension usually comes about when parking/unparking & as long as back-pedaling is minimised then chain drop can be avoided. I believe the Alfine hub also has some slight drag when rotating backwards & so vigorous back-pedaling while riding can also achieve increased chain slack & sag over the rear frame tube; hey presto, chain drop?!
Now I think I may have resolved the issue, through setting up a “chain keeper” for the section of chain closest to the rear cog (thereby maintaining chain alignment over the cog teeth). The next 2 pics show my chain keeper in situ with the chain taut (pic 1) & chain sagging (pic 2). My keeper?: a large-sized cable tie (working great). Maybe not what Brompton would do?
“Oh no, Adam is closing Cheeky Transport??”, I think was my reaction recently at seeing the FB news. Following the call for the final Cheeky Brompton ride, we had to be there…
Saturday arvo & we perused all the Brompton parts goodies & I reserved various wheels, a rack, mudguards, etc & then turned to ratting through various boxes of assorted bits…
Finally it was time for the final ride…
As usual, Adam & Nick led us through a myriad of back roads, parks & paths, heading for our much-anticipated Asian dumplings at Wolli Creek. Our route took us past the airport & we just had to stop under the flight path to marvel at the wobbly jets… (oh yes, we also endured some gusty winds)
Once again, all the food & beer got consumed without a thought to any pics – sorry about that.
A few days later I was back at the shop, collecting all my Brompton parts goodies. Adam was soldiering-on, cheery as ever but I see this as a sad pic; prepping his last Brompton orders in his last week of his 15 year shop operations?
Now we’re only left with the Friday Party & Saturday Garage Sale (refer poster below). Thanks Adam, it’s been a pleasure.
Tough night tonight. Had my last ride on Robinson & then Robinson took its last ride in the Tardis – to a new owner in Sydney…
As my original Brompton & source of initial education for riding, upgrades & maintenance, Robinson was greatly valued & appreciated. On behalf of Mrs Aussie & I, as well as Peregrine, Clarence & Ralph-e, we salute you. Farewell Robinson.
My bidon cage system had a minor improvement recently so I thought I should post the latest version info.
The change was to using clear tubing as insulating protection where the cage contacts the stem (I’d previously used various rubber pads but their attachment wasn’t ideal – no issues in practice but “could do with fixing”). The other components are two aluminum strips (8mm by 3mm), some fixings & two 58mm ID O-rings.
Taking a standard bidon cage & assembling my bits, it’s ready for attaching to a Brompton stem…
Once in place, the system looks like this…
Probably my longest running & most essential “hack”, the system performs perfectly. A bidon is held securely & the system doesn’t move around, although it’s also able to be swung left or right if necessary (e.g. folding the bike with a luggage bag in place or folding the bike for packing). The system is able to be removed readily but I’ve actually never needed to take it off. Of course, there’s bound to be another version at some stage – & I’m thinking 3D-printing could be utilised?
Updated – 7/1/17 (refer end of post)
My Brompton bidon cage system is still my favourite but it doesn’t suit someone that wants to use their folded Brompton as a shopping trolley, with handle bars unfolded & a bag on the luggage block – because the cage would foul the bag & regularly removing/installing the cage is best avoided. (Whoops, see update below.) A cage that is readily removable is the Monkii system but after trying one for some time, I’m not keen on 2 aspects of the design. First, I don’t like strapping the bottle to the cage & having to remove the two together when drinking. The killer issue though, is that the Monkii cage can readily be ejected when riding over bumps. So, here’s my attempt at fixing those 2 issues…
Peregrine with the old system…
… & Clarence with the new setup…
Here’s a pic of the old & new components…
Recipe: take one Monkii system, remove the strap & cut off the wings & tail of the cage. Drill & countersink the cage spine & attach to a standard cage with some screws & nuts. When the Monkii stem block is being mounted, hook an O-ring under the block. When installing the new “combo cage” to the bike, hook the top of the cage under the O-ring & stretch it up so that the Monkii portion of the cage can be connected to the Monkii stem block.
So, I now have a Monkii system that lets me easily remove/attach the bottle when drinking & won’t become disconnected over bumps – & lets me readily remove the cage when operating in “shopping trolley mode”!
Update: Since using Ralph-e & trying to avoid removing the luggage bag (& disconnecting the battery), I now realise that I can leave my Bidon in the cage system & the bag just pushes the Bidon to the side (as the bag pivots around while folding the front wheel).
The very best of wishes for the New Year to you from the Aussie household. We’ve had a very interesting 2016 year & I’m sure that regular readers of the blog have observed the many outings & happenings of the Brompton family.
The introduction of Ralph-e reminds me that Brompton are also crafting an e-bike so maybe a good time to offer my experience & recommendations?
Accordingly, “a Plea to Mr Brompton…”
I’d like a lightweight mid-drive Pedelec Brompton with torque-sensing BB & on-bike battery storage, easily removable (aircraft-legal, 100Wh module units), but not impinging on luggage capability. I’m also happy to use my local hills for testing of various gearing options, & undertake frequent travel to review in-field scenarios not available to UK residents. (e.g. why wait to get your hot weather testing done?)
Christmas Day & 33° (no white Christmas around here?) saw a family gathering at the Aussie household.
“Brompton” kept watch for arriving guests…
The feasting included both cold & hot creations…
Some of my goodies included a folding table for the Tardis, a well-ventilated Urban lid & the chance to retain some cork-removal skills?
Oh, & Ralph-e did manage to get out for a local Christmas-lights ride after the Boxing Day recovery!
Seasons greetings to all from the Aussie household – & the Brompton family…
What did the year bring? Between Mrs Aussie & I, we did the London BWC & Sydney BUC & got another Pennants badge. Pretty good BBB year I’d say? (i.e. Brompting, Blogging & Bowling)
Two Brompton bike shop-arranged Christmas Rides & picnics, two cities & one week apart? How good would this be? Getting to the Cheeky Transport ride in Sydney was our usual multi-modal affair, with trains & riding. The following week our Tardis transported us to Newcastle for Metro Cycles’ ride to Stockton.
Group rides & taking pics for the blog never seem to come together for me (just like Brompton events never having enough chat time?). So, in grabbing some of the pics from other sources, I should acknowledge them – but I’m struggling to identify all the snappers (so thanks to all?)
Cheeky’s ride started from the Newtown shop & headed to Brighton via back roads, lanes, cycle paths & whatever (hard to describe, difficult to remember the twists & turns, happy to chat & follow?). Adam guided us well, showed us sights we didn’t expect & delighted 11 riders (9 Bromptons & 2 big-wheelers) all the way to a Brighton Fish & Chips snack & then back to yummy nosh at the Concordia Club at Tempe. A great time for all; another successful Cheeky adventure.
Burning up the road for our group pic?
Market gardens near Sydney airport? Who knew?
A week later & our Northern cousins, the Newcastle Brompton Club, held their inaugural ride & we just had to go. On Friday the Tardis took us to Stockton Beach caravan park, just as the rain arrived (so Ralph-e & Peregrine kept under cover).
On Saturday we went multi-modal (ride & ferry) back into the city – with a brief stop to avoid a rain storm.
Sunshine from Metro Cycles onwards was well received & 14 Bromptons headed out, riding for the ferry to Stockton & then a tour of the peninsula. Our turnaround was under the Stockton Bridge & time for a good chat.
Taking over one of the picnic shelters (just opposite Nobbys Head), it was time for the group photo attempt & then it was time to unload all the picnic goodies & celebrate. Many thanks for Metro’s Bernie (& Lynn & Gus) & the ever-present Nick “Mr Brompton”. I suspect it won’t be our last Newcastle club ride?